Y2 Neuroscience

which receptor carries most of the fast voltage changes on postsynaptic CNS neurons, AMPAR or NMDAR?

AMPAR (NMDAR only opens after depolarisation has begun)

which system is also known as the 'vegetive' system

ANS

which genes are linked to alzheimers

APP (amyloid precursor protein, chromosome 21), presilin 1 and 2 (chr 14), and Apolipoprotein ε4 allele (chr19)

anterior spinal artery syndrome

ASA becomes occluded, damaging ventral portion of spinal cord at that level - eg patient has fine touch/proprioception *without pain + temp*

3 types of MS plaques

Acute (full of inflammatory cells), remyelinating (months after the acute T cell attack), burnt out (remyelination ceased)

what is ARMD

Age-related macular degeneration. painless loss of vision in the center of the visual field (the macula) because of drusen/damage to the retina.

outward current VS inward current

An inward current is the result of an influx of positive ions (usually Na+, Ca2+) or an efflux of negative ions. An outward current is the result of an influx of negative ions (usually Cl-) or an efflux of positive ions (usually K+)

which part of the brain especially seems to be able to regulate the emotional variability of pain?

Anterior cingulate cortex (ACC)

name 2 spinothalamic syndromes

Anterior spinal artery syndrome: artherosclerosis ors pinalinjury. Syringomyelia: occlusion of crossing pathways by degenerative expansion of the spinal central canal *both deficits in pain + temp sensation*

which adrenoceptors are present in blood vessels?

B2 (dilation), a1 (constrict), a2 (constrict/dilate)

what role does the basilar membrane play in hearing complex sounds?

BM is tuned along its length for sound frequency (membrane is widest at apex = lowest sound). it splits complex sounds into their constituent components.

which factors change during 'fight or flight response' to danger

BP↑ Heart Rate ↑ Pupils dilate. Blood supply to Skeletal Muscle in the limbs ↑ Blood supply to skin, kidney, digestive tract ↓ Respiration ↑ Blood Glucose ↑

which is more common, Central Vein Retinal Occlusion or BRVO?

BRVO is 3 times more common

who coined the term long term potentiation?

Bliss and Lomo - first to demonstrate Hebb's ideas in living tissue

what are the most common type of sensory axons?

C fibres

elbow flexion/supination reflex has which nerve roots?

C5,C6

after arising in the root of the neck, the vertebral arteries pass into the transverse foramen of which vertebra?

C6 (it skips C7)

elbow extension reflex has which nerve roots?

C6,C7

how many CAG repeats are present in IT15 in juvenile onset huntingtons?

CAG>60-70

which causes more perinatal deaths, neural tube defects or congenital heart defects?

CHD

tuberoinfundibular pathway

DA pathway from hypothalamus to infundibular region (median eminence). DA released here *inhibits prolactin release from ant pituitary*

mesolimbic pathway

DA pathway from ventral tegmental area to nucleus accumbens. affects motivation, emotions, reward

mesocortical pathway

DA pathway from ventral tegmental area to prefrontal cortex, involved in cognition/executive functions

nigrostriatal pathway

DA pathway projecting from substantia nigra PC to the striatum, involved in stimulating/planning purposeful movement

name some agonists of dopamine receptors D-2, 3, and 4

DA, bromocriptine

benserazide

DOPA decarboxylase inhibitor, which is unable to cross the blood-brain barrier

where are declarative memories and procedural memories stored?

Declarative memories are dependent upon forebrain and limbic structures. Procedural memory (with a strong motor component) is dependent upon the cerebellum

DNMS

Delayed non-match to sample; a test of recognising objects (*recognition memory*) that have been seen recently (over seconds to minutes).

give some psychological symptoms of depression

Depressed mood, Anhedonia, Low self-esteem, Guilt, Cognitive deficits, Poor concentration, Feeling of 'hopelessness', Suicidal thoughts, Hypochondria

name some agonists of dopamine receptors D-1 and D-5

Dopamine, aka DA. Amphetamine (indirectly... it releases DA)

difference between EOAD and LOAD

Early onset alzheimers disease = before 65. much less common. LOAD is after 65 yrs old - much more common (97% of cases)

what is EPSP

Excitatory post-synaptic potential. synaptic potential that makes a postsynaptic neuron more likely to generate an action potential, due to postsynaptic influx of cations causing depolarisation

EPS

Extrapyramidal symptoms; movement disorders like spasms, parkinsonism and dyskinesia, often side effects of anti-psychotic drugs

general anaesthetics exert their main effects on which bodily system?

CNS

glioma

CNS tumour arising from glial cells. rarely curable, with a poor prognosis

describe plasticity in pain system at a spinal level

Central sensitization, long-term potentiation, disinhibition

why does opening of postsynaptic Cl- channels cause an IPSP?

Cl- flows in down its conc gradient, making the membrane potential more negative and less likely to reach threshold (hyperpolarisation)

IT15 gene codes for what? what is the gene aka?

Codes for huntingtin, a protein which is mutated in huntingtons disease. Is aka Huntingtin gene, HD gene or HTT gene

name 2 neurodegenerative diseases linked to *prion protein* aggregation

Creutzfeldt-Jakob-Disease, Gerstmann-Straussler-Scheinker-syndrome

which fungus can cause meningitis

Cryptococcus neoformans - typically more indolent presentation. - Immunosuppressed (especially HIV and transplant recipients)

what is the difference between Gi and Gs proteins?

Gi are inhibitory (decrease cAMP), Gs stimulatory (increase cAMP).

name all the cranial nerves

I Olfactory II Optic III Oculomotor IV Trochlear v Trigeminal VI Abducens VII Facial VIII Vestibulocochlear IX Glossopharyngeal X Vagus XI Accessory XII Hypoglossal

why are inner hair cells and outer hair cells described as active and passive?

IHCs passively react to the travelling soundwave in the basilar membrane by opening channels/releasing neurotransmitters... whereas OHCs react by *actively* changing shape

which neurotransmitters do neurons of the ventrolateral preoptic nucleus contain? are they excitatory or inhibitory?

GABA and galanin (Gal), both inhibitory

opiods inhibit what to reduce dopamine?

GABA neurons

are GABA receptors ionotropic or metabotropic?

GABA*A* is *ionotropic* (a chloride channel) and GABA*B* is *metabotrophic*

benzodiazepines rely upon which neurotransmitter to function?

GABA. they accentuate GABA A receptor opening of Cl- channel

what is meningitis

Inflammation of the meninges - layers of connective tissue surrounding the brain and spinal cord, forming the blood-brain barrier

where in the CNS is the 'switch' from urine storage to micturition initiated?

Pons Micturition Centre in the brain stem

how does pleasure affect sensitivity to pain?

Positively rewarding activities generate analgesia - due to endogenous opiate peptides & cannabinoids, and dopamine pathways

age-related hearing loss is AKA?

Presbycusis

what is the link between psychological distress, acute pain, and chronic pain?

Psychological distress and intensity of acute pain predict development of acute into chronic pain - from injury, surgery, illness, etc

how on an ECG can you easily classify arrhythmias into supraventricular or ventricular?

QRS complex wider than 3 squares = ventricular, QRS narrow = supraventricular

which is more potent, R-(+)-etomidate or S-(-)-etomidate?

R-(+)-etomidate is 5 to 10 times more potent as a general anaesthetic

which type of sensory receptor only responds to a *change* in stimulus/pressure?

RA (rapidly adapting)

which is more sensitive, RA1 or RA2 receptors?

RA2 (pacinian corpuscle - larger and high sensitivity)

in which part of the night is most REM sleep?

REM

in which stage of sleep does dreaming occur?

REM

in which stage of sleep are eye movements most prominent

REM sleep

which of these ions are more concentrated inside the cell than outside: Ca, K, Na, Cl?

K

AMPAR and NMDAR allow which key ion to *exit* postsynaptic neurons?

K+ (they are non-specific cation channels, so alongside influx of Na+ etc, K+ will flow out down its conc gradient)

why is an increase in extracellular K+ so dangerous?

K+ ion is essential for coordinating resting potential; a raised extracellular conc would decrease the concentration gradient (usually much more K+ inside cell than out) and depolarises cells - would kill you rapidly

what is the formula for the supply of the extraoccular muscles

LR6(SO4)3

LTM

Long term memory: a system assumed to underpin the capacity to store information over long periods of time

which has larger receptive field, SA1 or SA2 receptors?

SA2 (ruffini endings are musch larger than merkels fibres)

which two key morphogens begin to generate distinct ventral and dorsal spinal cell types in development?

SHH and BMP (bone morphogenic proteins)

venlafaxine

SNRI antidepressant; blocks serotonin and noradrenaline reuptake (SNRI)

citalopram

SSRI antidepressant. highly selective for blocking SERT

which are the preferred drugs to treat depression

SSRIs

SSRI

Selective serotonin re-uptake inhibitors. treat depression + anxiety. they limit reabsorption of serotonin into presynaptic neurones, increasing 5HT in the synapse

moclobemide blocks which enzyme?

MAO A

which MAO type metabolises noradrenaline and 5-HT?

MAO A

phenelzine and tranylcypromine block which enzyme?

MAO A and MAO B

which MAO type metabolises dopamine?

MAO A and MAO B

which MAO type metabolises tyramine?

MAO A and MAO B

in which major disease does the myelin around CNS neurons degenerate?

MS

what is the commonest demyelinating disease?

MS

oligodendrites degrade in which major disease?

MS (causes the decrease of myelin)

which diseases are likely causes of internuclear ophthalmoplegia

MS (in young) or stroke (in elderly)

name 4 opiod receptors

MU, DELTA, KAPPA, ORL1

schemata

Models of the world that provide a framework for the interpretation of new and stored information

describe plasticity in pain system at a supraspinal level

Modulation and modification of nociceptive and antinociceptive synaptic transmission

give 6 antidepressant medical treatments

Monoamine oxidase inhibitors, Tricyclic antidepressants, SSRIs, NRIs, Mixed action, Electroconvulsive therapy

3 common causes of sudden visual loss

Most vascular events, Retinal detachment, Acute angle closure glaucoma

chemical formula of nitrous oxide

N2O

which general anaesthetic has been linked to megaloblastic anaemia?

N2O

neurons of the locus coeruleus contain which neurotransmitter

NA

why is glutamate considered a target for schizophrenia treatment? why might it be dangerous to target?

NMDA antagonists mimic some positive and negative symptoms of schizophrenia. however, too much glutamate can be neurotoxic, stimulating opening of ion channels and influx of Ca2+, resulting in mitochondrial stress and overproduction of ROS - leading to cell death

ketamine, N2O and xenon are non-competitive agonists of which major receptors in the CNS?

NMDA glutamate receptors

name 2 glutamate receptors

NMDA receptor, AMPA receptor

which major glutamate receptors enable transport of calcium ions

NMDA receptors

purkinje cells of cerebellum lack which key glutamate receptors

NMDARs

which has a larger synaptic cleft, NMJ or CNS synapse?

NMJ

chemical formula of nitric oxide

NO

carbamazepine

Na+ channel blocker taken as a tablet which is good at relieving neuropathic pain in trigeminal neuralgia

what are class I anti-dysrhymic drugs? give examples

Na+ channel blockers. 3 groups; *1a* eg disopyramide , *1b* eg lidocaine, *1c* eg flecainide

negative cognitive triad

Negative view of the self, the world and the future

which two key receptors does ACh act on as a neurotransmitter

Nicotinic (fast, ionotropic) and muscarinic (slow, metabotropic)

4 lobes of cerebrum

Occipital, Parietal, Frontal, Temporal

which receptors does ATP act on as a neurotransmitter in the CNS?

P2X (fast, ionotropic) and P2Y (slow, metabotropic)

primary motor cortex is abbreviated to what?

PMC

pedunculopontine tegmental nuclei

PPT nuclei: found in the tegmentum of the brainstem. Send cholinergic neurons to many forebrain targets eg thalamus + basal ganglia, involving them in alert/attentiveness, reward, movement and REM sleep

mutations in which gene is the most common cause of familial alzheimers

PSEN1 (presilin 1)

what is the general outline of a somatosensory afferent pathway from the periphery into the CNS?

Peripheral nerves, dorsal root ganglia, sensory terminals in spinal cord grey matter, pathways to the brain

most drugs which treat psychosis focus on metabolism of which substance?

Pi

what causes fast/exaggerated tendon reflexes?

UMN lesions, hyperthyroidism, cerebellar disease

polyneuropathy

damage or disease affecting peripheral nerves (peripheral neuropathy) *across both sides of the body*, usually spreading from the feet and hands centrally

brown-sequard syndrome

damage to one half of the spinal cord, resulting in paralysis and loss of proprioception on ipsilateral side below lesion, and loss of pain and temperature sensation on contralateral side (due to where nerve tracts decussate in spinal cord)

what does a lack of pupillary light reflex indicate? why?

damaged optic/oculomotor nerve (eg by brain swelling) or brain stem death

taste sense is carried in which cranial nerves

VII and IX (facial and glossophrngeal)

hearing and vestibuar function is carrier in which cranial nerves

VIII (vestibulocochlear nerve, aka auditory nerve)

side effects of anaesthetics

death if overdose,

what is the relationship between decibels and Bels?

decibel = 1/10 of a Bel

how does accomodative power of lens change with age?

declines from birth

most of the caudal medulla is taken up by what?

decussation of pyramids

role of schwann cells in axonal regeneration

dedifferentiate and proliferate to create a permissive environment for axonal regeneration. help remyelinate

is body muscle more active in light or deep sleep?

deep sleep (body is capable of movement eg adjusting position - whereas in REM, muscles except eyes are paralysed

how does huntingtons disease affect basal ganglia

degeneration of striatal neurons projecting to GPe causes disinhibition of indirect pathway

subacute combined degeneration of spinal cord

degeneration of the dorsal/lateral columns of cord due to vitamin B12 deficiency, usually associated with pernicious anemia

spondylosis

degenerative osteoarthritis of the joints between the center of the vertebrae. common cause of back pain in elderly

is the activation of K+ channels in action potentials rapid or delayed?

delayed

function of pain

demands attention so you look after yourself. prioritises escape and promotes recovery and healing of wounds. also *teaches* us to avoid things that hurt

which is usually thinner, the dendrites or axon of a neuron?

dendrites

is ACh increased or depleted in cerebral cortex of alzheimers patients?

depleted (hence AChE inhibitors are given)

which two findings are required for the clinical diagnosis of alzheimers in a post mortem brain?

depositis of plaques (beta amyloid) and neurofibulary tangles (tau)

pregabalin

derivative of GABA given to treat epilepsy, anxiety + neuropathic pain. increases GABA biosynthesis, and binds to calcium channels

name 2 class IV anti-arrhythmic drugs

Verapamil and diltiazam

name 4 main causes of painless visual loss

Vitreous Haemorrhage, Central retinal artery or vein occlusions, Arteritic or nonarteritic anterior ischaemic optic neuropathy, Age-related macular degeneration(ARMD)

lateral medullary syndrome is AKA

Wallenberg syndrome or posterior inferior cerebellar artery syndrome

heredodegeneration

describes disorders which become gradually worse (usually neurodegenerative) that are passed down from one generation to the next.

extra-axial

descriptive term to denote lesions that are external to the brain parenchyma

in vivo, imipramine is metabolised within minutes into which compound?

desipramine (a NA uptake inhibitor)

what is the effect of suprachiasmatic nucleus lesions?

destroys 24hr circadian rhythm of sleep/wake + activity. however, sleep patterns still coordinate to match light and dark

what is *the* major cause of autonomic dysfunction clinically?

diabetes mellitus (can cause impotence, impaired bladder function, disordered gut motility (intermittent diarrhoea and constipation), altered BP control)

how is RA and SA sensory information processed differently in the cortex?

different columns in each area of the homunculus map in the somatosensory cortex

how do we hear *pitch* ?

different frequencies of sound get a peak vibration in different places on the basilar membrane (due to its structure). The point of peak vibration of the basilar membrane causes the most bending of the stereocilia, so elicits the most response from the hair cells in that part of the cochlea.

dysarthria

difficult or unclear articulation of speech that is otherwise linguistically normal

reticular activating system

diffuse network of nerve pathways in the brainstem connecting the spinal cord, cerebrum, and cerebellum, and mediating the overall level of consciousness

DWI

diffusion weighted imaging; form of MRI based upon measuring the random motion of water molecules within a voxel of tissue; useful for tumours and cerebral ischaemia

where is the subthalamus

directly below the thalamus and above the mammillary bodies. posterior to hypothalamus

receptor potential

a *graded* transmembrane potential difference produced by activation of a sensory receptor (usually caused by inward current flow)

describe the neurons in the *general sensory* pathway

a *primary afferent/first order neurone* runs from the receptor into the ipsilateral CNS via either a spinal nerve or the trigeminal nerve. this links to an ipsilateral *second-order neurone* which decussates and ascends to thalamus. *third order neurone* projects from thalamus to somatosensory cortex

which cognitive abnormalities are seen inunipolar depression

a bias towards negative material seen in memory, attention.

lesions in multiple sclerosis often surround which structure? why?

a blood vessel, because this is how the T cells make their way into brain

commisure

a bundle of nerve fibers that cross the midline at their level of origin or entry

typology

a classification according to type

basal ganglia

a collection of subcortical nuclei at the base of the forebain, involved in voluntary movement, procedural learning and habitual behaviour.

rhodopsin

a coloured, light-sensitive protein present in the rods of the retina. helps activate the visual phototransduction pathway by *closing Na+ channels in rod cells in response to light*. also gives the retina its purplish-red colour

full thickness corneal laceration

a cut on the cornea which strikes deep enough to go completely through the cornea, causing a ruptured globe - very painful, weeping eye. iris tissue can prolapse into lesion

detrusor-sphincter dyssynergia

disease where urethral sphincter contracts at the same time as the bladder contracts - results in impaired voiding which can eventually lead to kidney failure. consequence of a neurological pathology such as spinal injury.

syringomyelia

disorder in which a fluid-filled cavity (syrinx) forms within the spinal cord, expanding + compressing nerve fibres in that transverse section of the spine-usually cervical (muscle wastage in hand/loss of sensation + pain)

subfalcial herniation

displacement of the cingulate gyrus from one hemisphere to the other, under the falx cerebri

cytotoxic oedema (brain)

disruption in cell metabolism impairs functioning of Na/K pump in the glial cell membrane, leading to swelling of individual glia/neurons with sodium and water

how might disturbed sleep patterns cause depression?

disturbed sleep has been linked to decreasing memory retention, particularly of *positive events* more than negative events

potassium-sparing diuretic

diuretic drugs that do not promote the secretion of potassium into the urine; used in hypertension/congestive heart failure. eg spironolactone

left/right visual hemi-field

division of the full visual field down the midline into left and right

SOD-1

a gene which codes for multiple enzymes which destroy free superoxide radicals in the body. can exibit a vast array of different mutations - all of which give rise to motor neuron disease

frequency tuning curve

a graph of auditory threshold intensity at various frequencies for a single neuron

psilocybin

a hallucinogenic alkaloid, found in some toadstools

engram

a hypothetical permanent change in brain/physical storage of *memory*

what does 'stigma' mean in greek?

a mark made by a pointed object

what is PA2?

a measure of the affinity of a competitive antagonist for its receptor

role of NO in the body

a messenger; inhibits vaso-adhesion+constriction(particularly in erections - viagra enhances this effect)/modulator of hair cycle/neurotransmission/secreted as free radicals in immune response/

which gene causes huntingtons

a mutated version of huntingtin gene (codes for huntingtin protein)

Oculomotor nucleus

a nucleus in the midbrain, which lies in the gray substance of the floor of the cerebral aqueduct, and gives rise to the oculomotor nerve

MDMA toxicity

a parallel reaction to the tyramine cheese reaction; MDMA blocks MAO, causes VMAT 2 to release seratonin cargo uncontrollably. can cause death

blind spot

a part of the visual field (*not eye itself*) where light falls on the optic disc, which has no light sensitivity

red nucleus

a pink structure in the rostal midbrain involved in motor coordination. relays info from motor cortex + cerebellum to cerebellum (via inferior olivary complex) and contralateral rubrospinal tract

which risk factor is 2nd to age for alzheimers

a positive family history (Genetic factors estimated to account or 30%-70% of risk)

cathine

a psychoactive CNS stimulant drug, with 10-15% the potency of amphetamine (not to be confused with caffeine!)

define: sleep

a readily reversible state of reduced responsiveness to, and interaction with, the environment

sound spectrum

a representation of a sound in terms of the amount of vibration at each individual frequency. usually presented as a graph of pressure as a function of frequency

VEGF

a signal protein produced by cells that stimulates vasculogenesis and angiogenesis; produced when blood circulation is inadequate

oto-acoustic emissions

a sound which is generated from within the inner ear

rexed laminae

a system of ten layers of grey matter to label portions of the grey columns of the spinal cord

tianeptine

a tricyclic antidepressant with a difference; it has been shown to *increase* monoamine uptake, increase BDNF, and indirectly alter glutamate activity

which instrument could you compare the basilar membrane to?

a xylophone (gets wider and lower pitch towards apex)

perinatal deaths

babies which die before reaching a month old - includes stillbirths

are photoreceptor cells found in the back or front layer of the retina?

back (seems impractical but there we go)

what are the 5 most common body locations of chronic pain in europe?

back, knee, head, leg, joints

difference between bacterial and viral conjunctivitis?

bacterial is more 'sticky' and pussy, whereas viral is more watery. bacterial has a lesser degree of erythema

oligoclonal bands

bands of immunoglobulins secreted by plasma cells that are seen in electrophoresis of blood serum/CSF. if seen permanently in CSF, suggests MS

thermoreceptors

bare nerve endings in skin, cornea, bladder. can be either warm (detect warming >37oC) or cold (detect cooling <37oC). sensitive to changes of <0.1oC + have small segregated receptive fields; tiny warm- and cold-sensitive patches alternate across skin surface

name the grey matter surrounding the (white) internal capsule

basal ganglia

is the basilar membrane stiffer at the base or the apex?

base (about 100x stiffer)

what is the difference between Ia, Ib, and Ic antiarrhythmic agents

based on how fast they associate/dissociate with sodium channels: Ia is medium, Ib fast, Ic slow.

which dopamine receptors are inhibitory?

basically all of them (D-1 to D-5)

which two arteries feed the circle of willis

basilar and internal carotid

auditory transduction

basilar membrane moves up and down, stereocilia of the inner hair cells rub against the tectorial membrane. The bending of the stereocilia produces electrical response in the hair cells

which is superior in the brain, meyers or baums loop?

baums

which pathway in the optic radiation enables you to see inferior visual field?

baums loop

why does the current of Na+ ions flowing through channels decrease whilst more and more Na+ channels are opening?

because as more channels open, cell membrane gets nearer to the equilibrium potential of Na+ (which is no net movement of ions across membrane)

why is the resting potential of most cells close to the equilibrium potential of K+?

because at rest, the cell membrane is most permeable to K+ than to other ions (ie, more channels for K+ are open than for other ions in unstimulated cells)

why do rods provide less detailed images than cones?

because hundreds of them can connect to a single ganglion cell, meaning your brain can't distinguish between which individual rods are firing (whereas each cone has one ganglion cell to itself)

meyer-overton rule

because inhalation agents act through the lipid-rich CNS cells, anesthetic potency increases with lipid solubility

why should you always ask patients if they have any heart problems before giving lignocaine anaesthetic?

because it is also an anti-arrhythmic (interferes with heart rhythm

why is hippocampus referred to as a 'time machine'

because it is essential for episodic memory, which can be described

why might EpiPens be inefficient in a patient taking beta-blockers?

because salbutamol will have no effect

why might people with hearing aids report difficulties distinguishing sounds in background noise

because when outer hair cells are damaged, hearing aids can only amplify incoming sound, not replace the active 'sharpening' of sound wave that OHC prestin contraction enables

do ascending dorsal column neurons synapse before or after they decussate

before

name the two components to consciousness + their respective control systems

being *awake/alert* (reticular activating system) and being *aware* (cerebral cortex)

steognosis

being able to pick things up and work out what they are without looking; function controlled by parietal lobe

how do you interpret a glasgow coma scale score?

below 8 = coma. 9-12 = moderate head injury. above 12 = mild head injury

fasciculus gracilis receives info in which levels of the spinal cord?

below T6

the left spinal cord is lesioned. on which sides are the senses of pain, temp, proprioception, vibration and touch lost?

below the lesion, pain and temp are lost on the right hand side, and most touch, vibration and proprioception is lost on the left hand side

why can barbiturates kill you, but benzodiazepines not?

benzodiazepines bind to GABA A receptors and increase effect of GABA to open Cl- pore. barbituates directly open CL- pore; body has less control of this

which adrenoceptors are present in heart?

beta 1 and beta 2 - both stimulatory

tremor is mediated by which adrenoceptors?

beta adrenoceptors

which brain wave type is seen in REM sleep

beta waves

name 4 *non BDZ* ligands which bind to benzodiazepine binding site on GABA A receptor. Which are endogenous?

beta-CCE (endogenous), zolpidem, zopiclone, desmethyldiazepam

which proteins aggregate in alzheimers disease

beta-amyloid4 and Tau

normal eye pressure

between 10 and 21mmHg

which two cell types are all rods and cones in direct contact with?

bipolar cells and horizontal cells

which cells connect the rods and cones to the optic nerve?

bipolar cells followed by ganglion cells

bitemporal heminopia

blindness in temporal visual field of both eyes, caused by lesion of optic chiasm (only affects the fibres which are crossing in the chiasm, hence the fibres which see your nasal visual field are preserved)

entacapone

blocks COMT; often used as an add-on parkinsons drug to reduce breakdown of L-DOPA

Benzhexol

blocks actions of ACh in striatum; used to be used for parkinsons but can cause cognitive amnesia. now used for drug-induced parkinsons only (eg schizophrenia patients)

name the extra layer of surrounding epithelial cells of all blood vessels in the brain

blood-brain barrier

what restricts movement of immunologically important cells/molecules into the brain parenchyma

blood-brain barrier

Cytotoxic cerebral oedema

blood-brain barrier is intact but ion pumps in brain cell membranes are impaired by toxins, leading to cells swollen with water

what colour is the bone, grey matter, and white matter, fat, and air in CT scan?

bone is white, grey matter is light grey, white matter darker. air and fat are both black - don't get confused

how is the location of the preganglionic neurons different between symp- and parasympathetic nervous systems

both are within the CNS, but symp are within thoracolumbar segments T1-L2, and parasymp are found within sacral segments S2-S4 + specific nuclei in brainstem.

why is spirinolactone potentially lethal if combined with ACE inhibitor therapy?

both drugs raise potassium (especially dangerous in renal failure)

name 2 drugs from each of class Ia, Ib, and Ic of antiarrhythmic drug

a: quinidine, procainamide. b: lignocaine, phenytoin. c: encainide, ecainide

two point discrimination

ability to discern that two nearby objects touching the skin are truly two distinct points, not one. reflects how finely innervated skin is

lewy bodies

abnormal aggregates of alpha-synuclein protein that develop *inside* nerve cells in Parkinson's disease, Lewy body dementia + other disorders.

strabismus

abnormal alignment of one or both eyes; a squint. must be corrected in childhood for CNS development

astrogliosis

abnormal increase in the number of astrocytes due to the destruction of nearby neurons

catatonia

abnormality of movement and behavior arising from a disturbed mental state (typically schizophrenia) - lack of motivation to move

fasciculus cutaneus receives info in which levels of spinal cord?

above T6 (except face and ear)

above which spinal cord segment are there more than 2 dorsal column tracts of the spinal cord? How many are there?

above level T6. there are 4

abscess VS tumour

abscess is a swollen collection of pus within the tissues, usually due to infection. tumours are masses caused by abnormal proliferation of tissues

name two types of generalised seizure

absence seizures. tonic-clonic seizures

drugs taken by mouth tend not to have a high liability of dependency. why?

absorbed too slowly to produce a 'high' - there are exceptions eg alcohol and codeine.

what are the ABC and D treatments for hypertension?

ace inhibitors, beta blockers, Ca2+ channel blockers, diuretics

heroin is di-acetyl morphine. what is important about the two acetyl groups?

act as a carrier for the morphine so it crosses the blood brain barrier very quickly; this makes all the difference

how does parasympathetic stimulation affect the lungs?

act on smooth muscle of bronchi and bronchial arterioles to cause bronchoconstriction and vasoconstriction

what role does the cerebellum play in the vestibular reflex?

activated when the whole word slips - i.e. when your eyes move at different speed to head

why might an a2 agonist be used in glaucoma?

activates the α2-adrenoceptors on the ciliary epithelium, reducing cAMP concentrations and hence aqueous humour production. also increase uveoscleral outflow

why can't APs propagate along an axon without *active* membrane transport?

active Na+/K+ channels prevent the AP from fading as it propagates by allowing it to regenerate + run undecremented along axon

capsaicin

active component of chilli peppers, used as an analgesic in ointments/dermal patches/nasal sprays

5 checks of optic nerve

acuity, checking colour vision, visual field, reflexes, fundoscopy

red eye, mid-dilated pupil, clouded cornea, intense pain are characteristic of what?

acute angle closure glaucoma

how to differentiate between acute and chronic subdural haematomas on CT scan

acute are hyperdense (white) and chronic hypodense

in general, what are the main differences between acute and chronic pain?

acute pain: identifiable cause, resolves with healing, responds to treatment. chronic pain: much less likely to have those features. requires more psychological investigation

will patient's nystagmus adapt faster when spun in chair wearing a blindfold, or without blindfold? why?

adaptation (stable eyeball) occurs rapidly while *wearing blindfold*, but virtually doesnt occur without it. reason: when eyes are open, the *optokinetic reflex* can work to "remind body" that we are spinning, maintaining nystagmus even after endolymph has habituated and VOR is lost)

adjunct drug

added to another drug as a supplementary rather than an essential part

a loss of control over drug seeking behaviour is called?

addiction

synechia

adhesions between the iris and the lens or cornea resulting from trauma or eye surgery or as a complication of glaucoma or cataract; can lead to blindness

pneumoccal meningitis is most common in which age group?

adults

Internuclear ophthalmoplegia

affected eye shows impairment of adduction. When an attempt is made to gaze contralaterally, the affected eye adducts minimally, if at all. The contralateral eye abducts, however with nystagmus

does brown-sequard syndrome affect only the level of the lesion?

affects all sensory input at level of hemidissection on side of lesion, affects dorsal column below lesion on ipsilateral side, and spinothalamic below lesion on contralateral side

in which two key populations might Ca channel blockers be given to reduce hypertension?

african americans / elderly patients

in which two key populations might diuretics be given to reduce hypertension?

african americans / elderly patients

how does the somatosensory homunculus react to hand amputation and transplant of new hand?

after amputation, the face area invades upwards to occupy where the hand senses travelled (may feel phantom hand upon touching face). after transplant, hand signals area begins to restore.

what might causes an elderly lady to have a BP of 195/85mmHg, with a HR of 30bpm? how might you treat this?

age has caused bradycardia, which leads to longer filling time - hence greater CO, and a high systolic but low diastolic. treat by speeding up heart with a pacemaker

causes of hearing loss

age, loud noise exposure , ototoxic drugs (antibiotics eg gentamicin), genetic, stress (sudden hearing loss)

neurofibrillary tangles

aggregates of hyperphosphorylated tau protein most commonly associated with alzheimers.

Nucleus Tractus Solitarius

aka 'solitary nucelus' or NTS. nuclei forming column of grey matter in medulla, through which runs a white bundle of nerves - the 'solitary tract.' many functions including taste + autonomic reflexes

sylvian fissure

aka *lateral sulcus*. large diagonal fissure on the lateral surface of the brain that separates off the temporal lobe from frontal lobe

paraneoplastic syndrome

aka *non-metastatic* syndrome. disease/symptom caused by presence of cancer in the body, but not by local presence of cancer cells. effect is due to humoral factors excreted by/immune response to tumor cells

interstitial oedema (brain)

aka Hydrocephalus. CSF fluid oedema in periventricular white matter, due to a CSF drainage obstruction.

Subacute combined degeneration of spinal cord

aka Lichtheim's disease. degeneration of dorsal/lateral spinal coloums, affecting sensation/proprioception/lateral corticospinal tract. due to low vit B12 (often linked to pernicious anemia)

rexed's lamina II

aka substantia gelatinosa; dorsal part of the spinal cord grey matter where the first order spinothalamic neurons synapse

dejerine-roussy syndrome

aka thalamic pain syndrome. condition developed after stroke causing damage to thalamus. begins with numbness in contralateral side of body which develops into very severe chronic pain, with little treatment

spinal lemniscus

aka the anterior and lateral spinothalamic tracts

optic papilla

aka the optic disc - the area where the optic nerve enters the retina. is devoid of photoreceptor cells (blind spot)

hypervigilance

alertness; enhanced state of sensory sensitivity + exaggerated intensity of behaviors whose purpose is to detect threats. accompanied by a state of increased anxiety which can cause exhaustion

which vertebrae have transverse foramina?

all cervical vertebrae

5HT2a receptors are important why?

all drugs which activate them are class A controlled substances and are *all hallucinogenic* (LSD is included)

main visual areas of brain take up which lobes of the cortex?

all of the occipital cortex and much of the parietal and temporal cortex

out of the 7 5-HT receptors, which are excitatory?

all of them *except* 5-HT1 and 5-HT5

the left upper brainstem is lesioned. on which sides are the senses of pain, temp, proprioception, vibration and touch lost? why?

all of those sensations would be lost on the contralateral side, because all ascending somatosensory pathways decussate *in the spinal cord or lower brainstem*

why does post rotatory nystagmus last longer after spinning blindfolded?

along with vestibulo-occular reflex, the *optokinetic reflex* helps tell body that it has stopped spinning and is still; without vision, this cannot occur, so vision takes longer to stabilise

which adrenoceptors are found in the lungs?

alpha 1 - constrict, and beta 2 - dilate

which receptors are blocked by SSRIs

alpha 1 adrenoceptors, H1 receptors, muscarinic receptors

clonidine is an agonist of which receptor?

alpha 2 adrenoceptor agonist

benzodiazepines don't bind to GABA receptors with which alpha subunit?

alpha 4

which receptors 'blunt' the signal of monoamines in synapses?

alpha-2 adrenoceptors

which proteins aggregate in parkinsons disease

alpha-synuclein

Lewy bodies are composed primarily of what?

alpha-synuclein fibrils

ocular dominance columns

alternating bands in a striped pattern across the surface of the straite cortex (V1) that respond preferentially to input from one eye or the other. involved in *bilateral vision*

lesions can be used to destroy spinothalamic tracts to relieve pain. after months, pain comes back - why?

alternative tracts can learn to carry pain info, eg spino-parabrachial pathway

when does pain have a psychological component?

always

which is more common, parkinsons or alzheimers?

alzheimers (~ 10 times more common)

3 most common forms of dementia in order

alzheimers disease, vascular dementia, dementia with lewy bodies

skinner

american psychologist who believed free will was an illusion and human action depends on consequences of past actions. created 'behaviourism' and the operant conditioning 'skinner box'

tryptophan

amino acid which is necessary to make serotonin/ normal growth + metabolism. needs to be obtained from diet

classical neurotransmitters are which kind of chemical structures

amino acids (or derivatives of....eg catecholamines derived from tyrosine)

what is the main class III antiarrhythmic drug

amiodarone (though it also shows class I, II, III and IV action)

what was the difference between antidepressants and amphetamine in treating depression?

amphetamine would make patients "run to the bridge they were about to jump off of" - whereas antidepressants stop desire to jump.

how do your brainwaves change as you progress from REM through to stage 4 sleep

amplitude increases, and frequency decreases, through from beta rhythms to theta and delta

fear memories are 'stored' where in the brain?

amygdala

which old structure is important in the emotional response to pain?

amygdala

which part of brain seems to be involved in nondeclaratic classical conditioning emotional responses?

amygdala

name the key areas of the brain in the assessment of stimuli/decision making process/execution of commands

amygdala + parts of the cortex (especially prefrontal + insular cortex)

nordiazepam

an active metabolite of diazepam and other benzodiazepines, used primarly to treat anxiety

fornix

an arched structure in the body, in particular the area of white matter between the hippocampus and the hypothalamus

associative learning

an association between two stimuli or a behaviour and a stimulus is learned. The two forms of associative learning are classical and operant conditioning.

what is the medical definition of 'insult'

an event/occurrence which causes damage to an organ

describe 5-HT1 receptor, including agonists + antagonists

an inhibitory serotonin receptor - decreases firing of serotonergic neurons. agonists include 8-OH-DPAT and sumatriptan. antagonists include WAY 100635.

scotoma

an isolated area of diminished vision within the visual field

define pain in humans:

an unpleasant sensory *and emotional* experience associated with actual *or potential* tissue damage, or described in terms of such damage

main uses of ketamine

anaesthesia in: children, asthmatics, emergencies/war zones

why is recovery from anaesthetic longer in obese patients?

anaesthetics are very lipid soluble, and in long operations they can be absorbed into body fat. due to low blood flow of fat, may take weeks for effect to fully leave

what are the main actions of mu-opioid receptors

analgesia, resp depression, physical dependence, euphoria, miosis (pupil constriction)

superior quadrantanopia

anopia affecting a quarter of the field of vision. It can be associated with a lesion of an optic radiation

decussate

another word for ' cross or intersect '

foramen transversarium

another word for transverse foramen

difference between antagonist and inverse agonist

antagonists don't do anything themselves unless in conjunction with an agonist, which they block. inverse agonist binds to the same receptor binding-site as an agonist but produces an effect opposite to that of an agonist

what does a large PA2 value mean?

antagonists with a large PA2 have greater affinity to their receptors than ones with a small PA2

which corticospinal tracts *don't* cross the midline? what % of corticospinal fibres is this?

anterior (direct) corticospinal tract. about 5% of the fibres

difference between V1 ventral stream and dorsal stream?

both pathways from primary visual cortex, but ventral goes through V2 then V4 to the inferior temporal cortex; recognises objects. dorsal goes through V2, V6 and V5 to posterior parietal cortex; linked to object location/motion/contol of eyes & arms

which key vessels can be seen in a lateral view internal carotid angiogram?

anterior and middle cerebral arteries (not posterior as this arises from basilar not carotid). opthalmic artery also visible

which cortical areas are supplied by the anterior, middle and posterior cerebral arteries individually?

anterior cerebral arteries supply the anteromedial portion of the cerebrum. The middle cerebral arteries are situated laterally, supplying the majority of the lateral part of the brain. The posterior cerebral arteries supply both the medial and lateral parts of the posterior cerebrum

which arteries form the circle of willis

anterior cerebral arteries, anterior communicating artery, internal carotids, posterior cerebral arteries and the posterior communicating arteries

which artery supplies most of the superior medial surface of the brain hemispheres?

anterior cerebral artery

which artery is likely to cause a stroke which affects lower limbs only?

anterior cerebral artery (affects medial brain)

in the anterior cranial fossa, which artery usually causes epidural haematoma

anterior ethmoidal artery

circumciliary injection around the iris, photophobia, pain, misshapen pupil, and inflammation in anterior chamber is characteristic of which eye disease?

anterior uveitis

difference between anterior and posterior synechiae

anterior: iris adheres to cornea. posterior: iris adheres to lens

what are the boundaries of the parietal lobe?

anteriorly, the central sulcus. laterally, the lateral fissure. posteriorly there is no distinct boundary but medially there is a medial parieto-occipital sulcus

antidysrhythmic drugs AKA?

antiarrhythmic drugs

gabapentin

anticonvulsant used to control some types of seizures in the treatment of epilepsy; also used to manage neuropathic pain. Can cause confusion, so patients don't like taking it for long time

mianserin

antidepressant, anxiolytic, antiemetic and antihistamine drug which blocks histamine, serotonin, and alpha-adrenergic receptors. disinhibits release of NA, DA, 5HT, ACh.

most anti-anxiety drugs are also which kind of drugs?

antidepressants

what is the 'therapeutic lag' of antidepressants?

antidepressants usually take weeks/months to affect mood, even though chemical changes (eg serotonin increase) occur within hours. thought to be due to the body *downregulating* 5HT-1 receptors (timeconsuing genomic process)

how does the main neurotransmitter/receptor used by neurons differ between symp- and parasympathetic nervous systems?

both use ACh in the ganglion (nicotinic receptors), but symp uses NA at the effector (adrenoceptors) - except for sweatglands - whereas parasymp has ACh at the NMJ (muscarinic receptors)

where in cell is MAO found?

bound to outer membrane of mitochondria

tonsillar herniation

brain herniation where the cerebellar tonsils descend below the foramen magnum

list factors which could cause increased intracranial pressure

brain oedema (infarction/trauma/infection) haemorrhages, brain tumour/abscess, CSF drainage obstruction

where are opoid receptors found in body?

brain, brainstem, spinal cord, and peripheral tissues

theta waves

brainwaves detected via EEG in children and adults in light sleep

neuropathology

branch of medicine concerned with diseases of the nervous system, including brain biopsy/autopsy

central retinal artery

branch of ophthalmic artery that penetrates the optic nerve to enter eye at the optic papilla in the retina. divides into superior and inferior temporal and nasal arterioles

lenticulostriatal arteries

branches of the proximal middle cerebral artery, which supply the basal ganglia and internal capsule

what are the causes of vasogenic oedema

breakdown of the tight blood-brain barrier junctions due to *tumour/trauma/haemorrhage/infarction/abscess/lead intoxication*

tics

brief, involuntary movements which remain stereotyped in an individual through life; often emerging in times of stress

the great commisure

broad nerve cable + lesser bridges which connect the two halves of the brain; people function almost normally with this cut, but children who are *born without* it have major issues

corpus callosum

broad transverse white matter tract below the cingulate gyri connecting the two cerebral hemispheres

difference between wernikes aphasia and broca's aphasia

brocas is expressive - difficult to form words as a motor function. wernikes is receptive - can speak but wont make sense

name condition caused by spinal cord hemisection

brown-sequard

which disease presents with a loss of pain+temp contralaterally, and loss of touch+proprioception ipsilaterally?

brown-sequard syndrome

what causes hydrocephalus?

build up of CSF expanding ventricles of brain, due to blockage in flow of CSF

proptosis

bulging of the eye anteriorly out of the orbit

name some ventricular arrythmias

bundle branch blocks (between AVN and purkinje fibres), *ventricular tachyarrhythmias* eg ventri ectopic beats, ventric tachycardia, ventric fibrillation, torades de pointes

anterior commisure

bundle of nerve fibers (white matter), connecting the cerebral hemispheres across the midline in front of the columns of the fornix

dyskinesia

any abnormality in performing voluntary movement

sulci

any of the narrow grooves in an organ or tissue especially the brain surface

consensual response

any reflex observed on one side of the body when the other side has been stimulated, eg if if right eye is shielded and light shines into left eye, constriction of both pupils occur

difference between disarthria and aphasia

aphasia is disorder of language (understanding etc), disarthria is disorder of speech (slurring etc)

pain in T10 - T12 dermatomes could be referred from where?

appendix (if only T10) or testes, prostate, ovaries, uterus

driaze test

apply drug to eye surface to test for toxicity

limbic cortex

arc-shaped region of cortex; 'old' part of brain. controls the basic emotions (fear, pleasure, anger) and drives (hunger, sex, dominance, care of offspring)

which part of the medulla is an extension of the pontine nuclei of the pons, with the same cortico-cerebellar motor function?

arcuate nuclei

substantia gelatinosa

area at apex of the posterior grey column, aka rexed lamina II. contains many opiod receptors and is one of areas where 1st order spinothalamic tract neurons synapse

parasympathetic nucleus ambiguus

area in medullary reticular formation, contains parasympathetic neurons for slowing/weakening heart contractions (via the vagus)

entorhinal cortex

area in the medial temporal lobe and functioning as a hub in a widespread network for forming spatial memory and navigation. The EC is the main interface between the hippocampus and neocortex

broca's area

area located in left frontal lobe near lateral fissure important for motor production of speech

meningitis belt

area of africa with many epidemics, mostly due to *type A* meningitis, which has no vaccine

wernicke's area

area of cerebral cortex essential for understanding + forming language. only present on the dominant hemisphere, not both

primary auditory cortex

area of cerebral cortex; receives info from both ears

binocular visual field

area of the visual field which is an overlap between left and right hemi-fields

why might a drug be given sublingually?

area under the tongue has many capillaries so the drug can be absorbed directly into bloodstream without going through GI tract; so is usually faster and more effective.

how does the somatosensory cortex change after amputation?

area which supplies that limb will shrink over time

brodmann areas

areas of cerebral cortex based on histology - they relate suprisingly well to function

striate arteries

arise from the middle cerebral artery and supply deep structures in the cerebrum including the internal capsule and reticular formation. Strokes in these vessels are common and can cause extensive damage

red nucleus controls what aspect of typical walking?

arm swing

common general features of local anaesthetic chemical structures

aromatic group one end, and tertiary/secondary amino group the other end. linked by ester OR amide bond

which frequencies does noise induced hearing loss most affect?

around 4000 Hz

at which age does presbyopia set in?

around 45

most meningioma cases are at which age?

around 60

which vertebral level is behind the entry to the larynx?

around C4/5

which muscles cause hairs to stand up?

arrector pili

what causes locked-in syndrome

arterial disruption at the pons - branches of basilar artery supply pons, and some branches supply motor tracts and not sensory. damage to these causes locked-in syndrome

Beta 2 adrenoceptors are found in which kind of blood vessels?

arteries/arterioles to skeletal muscle (eg including coronary arteries)

AVM

arteriovenous malformation; abnormal connection between arteries and veins, bypassing the capillary system

what are the 4 most common causes of pain in europe?

arthritis, herniated/deteriorating discs, traumatic injury, migraines

meprobamate is licensed to treat which conditions?

as a muscle relaxant eg for MS -no longer licensed as anti-anxiety drug due to misuse

how does the central canal ascend in the brainstem?

as it ascends, passes dorsally, eventually opening into the diamond shaped 4th ventricle below the cerebellum

from their source, do tactile and proprioceptive tracts ascend on ipsilateral or contralateral side of the spinal cord

ascend ipsilaterally in the dorsal columns to dorsal column nuclei, after which they decussate to contralateral side

anterior spinothalamic tract

ascending pathway in outer latero-ventral edge of spinal cord. associated with conduction of soft nociceptive information to the reticular formation in the thalamus

spinoreticular tract

ascending pathway in the white matter of the spinal cord, positioned close to lateral spinothalamic tract. goes from spinal cord—to reticular formation— to thalamus. responsible for automatic responses to pain, such as in the case of injury

how do you assess pain when it is so subjective?

ask patient - verbal or numerical scale is the best way. Could use HR, BP, fMRI etc...but there are many other influences involved in those.

gate control model

asserts that non-painful input closes the "gates" to painful input, which prevents pain sensation from traveling beyond the dorsal horn. Therefore, stimulation by non-noxious input is able to suppress pain

which cells form the blood brain barrier around blood vessels?

astrocytes

what are the key clinical features and lab tests that aid diagnosis of MS?

at *least two lesions* in the CNS, separated in time and space. plaques seen in MRI of brain/spinal cord. *lumbar puncture*increased active lympocytes, raised protein, oligoclonal bands on electrophoresis. delayed conduction in visual pathways seen in VEP

how does demyelination affect AP conduction down axons?

at first, causes AP conduction to be blocked. over time, conduction is restored as Na+ channels become expressed - but is much slower

at what stage is the CNS first divided into forebrain, midbrain, hindbrain, and spinal cord?

at the end of neurulation

what is being off-balance due to cerebellum called?

ataxia

which drug would you give if a patient has an unshockable heart rhythm?

atropine

downsides of atypical neuroleptics vs typical neuroleptics

atypical have all the side effects of typical, plus more... a scary one being agranulocytosis

what kind of hallucinations are diagnostic of schizophrenia?

auditory - most often talking about you, eg your friends are plotting against you

describe the auditory pathway from the auditory nerve

auditory nerve fibre, ipsilateral cochlear nucleus, superior olivary nucleus, inferior colliculus, medial geniculate body, auditory cortex

superior temporal gyrus is involved in what function?

auditory processing

in a nutshell, how do all benzodiazepines work

augmenting effects of GABA at the GABA A receptor

pernicious anaemia

autoimmune attack destroys parietal cells in stomach, so they don't produce sufficient intrinsic factor for B12 absorption. leads to macrocytic anemia

vegetative system is AKA

autonomic nervous system

friedrich's ataxia

autosomal recessive mutation leading to reduced expression of mitochondrial protein frataxin, causing progressive nerve damage including ataxia

long-term memory

does not require continued rehearsal, has greater capacity and is quite resistant to disturbance from the brain (e.g. memory for familiar telephone numbers)

drugs with dependence-liability increase transmission of what in the nucleus accumbens?

dopamine

whcih enzyme is present in NA neurones but not dopamine neurons?

dopamine beta hydroxylase (enzyme which converts dopamine to NA)

what are the two main risks of just increasing dopamine in patients brain to treat parkinsons

dopamine can be converted to NA, which has many effects in the brain. also, often parkinsons is only loss of dopamine in one pathway in the brain; you don't want to overload the other pathways.

what key thing do these chemicals have in common: HALOPERIDOL CHLORPROMAZINE DOMPERIDONE?

dopamine receptor antagonists (uses include antipsychotics and antiemetics)

dopaminergic nigro-striatal pathway

dopaminergic pathway that connects the substantia nigra with the dorsal striatum - part of the basal ganglia motor loop

nigrostriatal system

dopaminergic pathway that connects the substantia nigra with the dorsal striatum. involved in movement production via basal ganglia

is the 'where' visual stream ventral or dorsal?

dorsal - projects to brodmann area 7 of parietal lobe - involved in proprioception/where an object is is space

which pathway contains *axons* of primary afferents, spinothalamic tracts, or dorsal column medial lemniscus pathway?

dorsal column medial lemniscus pathway (spinothalamic tract only contains the synapse of primary afferents entering spinal cord)

nucleus gracilis

dorsal column nuclei in medulla that participate in fine touch/proprioception of the lower body. contains second-order neurons of the posterior column-medial lemniscus pathway. sends axons that synapse in thalamus

name the 3 most important ascending spinal tracts and what they carry

dorsal columns (fasciculus gracilis and cuneatus): fine touch + proprioception to cerebrum. spinothalamic tracts - pain, temp, touch, pressure to thalamus. spinocerebellar tracts - muscle + joint receptor info to cerebellum

which part of brainstem contains dorsal column nuclei

dorsal medulla

tectum of midbrain

dorsal part of the mesencephalon, posterior to cerebral aqeuduct. responsible for auditory + visual reflexes

where is the 4th ventricle seen on the medulla?

dorsal surface; lies beneath cerebellum, ascends up into pons

name the main region in the spinal cord where grey matter extends out to the pia?

dorsolateral fasciculus (many unmyelinated axons)

what kind of joint is the temporomandibular joint

double synovial joint (two seperate synovial cavities, seperated by a flexible articular disc)

sialorrhoea

dribbling

side effects of neuroleptics

dribbling, hyperprolactinemia, sialorrhoea, EPS, aplastic anaemia, Neuroleptic malignant syndrome

carbidopa

drug given to people with Parkinson's disease in order to inhibit peripheral metabolism of L-DOPA. allows a greater proportion of peripheral L-DOPA to cross the blood brain barrier - boosts central nervous system effect of L-DOPA

phenacetin

drug introduced in 1960s which turned out to cause dangerous renal damage

practolol

drug introduced in 1970s, turned out to be extremely toxic and have adverse drug effects - lead to introduction of BNF yellow card

primary visual cortex is near which sulcus?

calcarine sulcus

what can abnormal hyperdense (bright) structures be caused by in head CT

calcifications or blood which has leaked out of vessels

otoconia

calcified deposits on top of the gelatinous ololihic membrane in a macula, which are affected by gravity and hence enable maculae to detect tilt information even when head is stationary

Hebb

came up with the idea that neurons which are connected and usually fire at the same time should be linked, as they are trying to represent the same thing; now called LTPs /connectionism.

how can we use the B2 adrenoceptors in the uterine muscle pharmacologically?

can agonise them to cause relaxation of the muscle (inhibits labour)

which antigens activate T cells to attack oligodendrocytes in MS?

can be MBP (myelin basic protein), PLP (proteolipid protein), MOG (myelin oligodendrocyte glycoprotein)

are benzodiazepines addictive

can be in industrial amounts -

what causes aneurysms?

can either be hereditary or acquired disease

why might fMRI be useful in treatment of brain tumour patient

can map areas of brain activation upon movements of eg speech can been seen in brain. can see how much these areas overlap with tumours; used to determine how aggressive surgeon can be (*surgical planning*)

tulving

canadian neuroscientist who separated declarative memory into 'semantic' and 'episodic'

which drug is usually used in partial seizures

carbamazepine

which drugs can you give to prevent L-DOPA being converted to dopamine outside the blood-brain barrier?

carbidopa

give 3 side effects of anaesthetics specific to halothane

cardiac arrhythmias, low BP, liver damage

digoxin

cardiac glycoside found in foxgloves (digalis species) which stimulates release of ACh. used in small doses to increase heart contractility and/or decrease heart rate

list factors which affect arterial pressure

cardiac output, total peripheral resistance, sympathetic and parasympathetic outflow, heart rate, stroke volume (and total blood volume)

disadvantages of ketamine

cardiovascular problems, increased intracranial pressure, red skin/rash, nausea, tonic-clonic movements, dependence, delerium/hallucinations, respiratory depression

is baroceptor reflex from carotid sinus or carotid body?

carotid sinus

dry eyes

dry, gritty, watering, sore, red eyes.

conductive deafness

due to interference with transmission of sound to the cochlea usually the result of obstruction of the ear canal/disease of middle ear

the dura mater consists of two fused layers, except in which locations?

dural venous sinuses, where the layers are unfused to form spaces for venous blood

beta rhythms are seen on an EEG when?

during normal waking consciousness, with eyes open

why is O2 given during recovery from some general anaesthetics

during recovery, anoxia may occur due to changing concentration gradients. giving extra O2 prevents this

sympathetic neuropathy

dying off of the sympathetic postganglionic neurons; frequent in diabetes type I and II

what is a growth cone?

dynamic, actin-supported extension of a developing axon seeking its synaptic target. has many projections called filopodia

slurred/ poorly articulated speech is called what?

dysarthria

which is more common, arrhythmia or dysrhythmia?

dysrhythmia

EPS side effects

dystonia (continuous spasms and muscle contractions), akathisia (motor restlessness), parkinsonism (rigidity, bradykinesia, and tremor), dyskinesia (jerky movements). occur from drugs like *typical antipsychotics* which agonise D2 receptors

signs/symptoms of parkinsons

Shuffling gait• Stooped posture• Freezing• Soft monotonic speech• Swallowing problems• Masked face• Executive dysfunctions -attention, impulse control,time, cues• Depression• Anxiety• Sleep• x 6 excess dementia

which mnemonic helps you remember the colour of CSF in T1 and T2 MRI scans

T t*w*o *w*ater is *w*hite (CSF is pretty much water)

grey matter is dark and white matter light. is this a T1 or T2 MRI?

T1

if ventricles appear dark on an MRI scan, is it T1 or T2?

T1

principle dermatomes for referred heart pain

T1-T8

principle dermatomes for referred appendix pain

T10

fat is not bright, white matter is dark, and grey brighter. is this a T1 or T2 MRI?

T2

name 2 key receptors involved in sensitising C fibres during inflammation

TRPV1 receptor and NGF:TrkA receptor

describe the anatomical steps in the pathway for memory formation from temporal lobe cortex/amygdala

Temporal lobe cortex, amygdala > dorsomedial nucleus of thalamus > prefrontal cortex

which 4 parts of the brain form the 'pain matrix'

Thalamus, somatosensory cortex, insula and anterior cingulate cortex

what does SMA stand for in the brain?

Supplementary motor area

name two common disorders causing cloudy optics

cataract (lens or cornea) and floaters (debris near retina)

which two conditions could interfere with stereopsis?

cataracts (congenital/those in young children). strabismus (squint)

in a patient taking alpha-adrenoceptor antagonists, why might EpiPens be dangerous in anaphalactic shock?

cause worse hypotension (activates the B2 receptors in vessels without the contradictory effects of a1)

how does opening of K+ channels in membrane cause inhibition of nerve impulses?

causes hyperpolarisation (more K+ can escape cell) and also decreases resistance and hence voltage change (more channels open)

how does hypoxia (with normal perfusion) change appearance of neurons?

causes them to become shrunken and eosinophilic (readily take up eosin dye)

amacrine cells

cells in retina which receive signals from bipolar cells. regulate bipolar + ganglion cell activity

what is the rhyme to remember the hebb rule

cells that fire together wire together, cells out of sync fail to link

is the mu opiod receptor peripheral or central?

central

what is the 1 *really* important branch of the opthalmic artery

central artery (of the retina)

scala media

central duct of cochlea; endolymph filled cavity inside the cochlea, located in between the scala tympani and the scala vestibuli

equatorial region of muscle spindle

central portion of muscle spindle - the non-contractile part, innervated by sensory afferents

pale retina with thin vessels is a sign of?

central retinal artery occlusion - starves retina of blood supply

why might touch start to feel painful after an injury?

central sensitisation; area of dorsal horn which senses pain expands to include the region which detects touch

difference between cerebellar and cerebral peduncles

cerebellar connect cerebellum to brain stem (superior, middle, inferior). cerebral peduncles are in anterior midbrain and connect the large sensory + motor tracts between the pons + cerebrum

name the grooves in the cortex of the cerebellum

cerebellar folia

which part of the cerebellum can potentially herniate through the foramen magnum?

cerebellar tonsils

2 types of mossy fibres

cerebellum and hippocampus

what is commonly blocked in hydrocephalus

cerebral aquaduct (between 3 and 4th ventricles)

name the dark hole seen in the posterior midbrain in T1 MRI

cerebral aqueduct

what are the 3 hallmark neuropathologies of alzheimers disease

cerebral atrophy, amyloid plaques, neurofibrillary tangles

which 3 tissues form the left + right cerebral hemispheres?

cerebral cortex (grey matter), subcortical white matter, deep nuclei (grey matter)

where do the principal afferent inputs to the basal ganglia come from?

cerebral cortex and thalamus

hyperpolarise

change in a cell's membrane potential that makes it more negative; the opposite of a depolarization

refraction

change in direction of a propagating wave (light or sound) when passing from one transparent medium to another

how can conditioned cues be used to treat drug seeking behaviour?

change/remove environmental cues - there will be a *conditioned place preference, place withdrawal, and tolerance* for drug seeking behaviour.

which structural changes are seen in the brain in those with chronic pain?

changes in activation patterns/descending modulatory system: inhibitory system underactive and/or descending facilitatory system overactive. also abnormal dopaminergic system + death of PFC cells

what is the purpose of face and body expression during pain?

changes in posture can be protective (reduce/prevent worse pain). facial expression has no protective function; is communicative, warning those who see it and eliciting help

GABA and glycine act as neurotransmitters on which key postsynaptic channels?

chloride channels. (glycine also helps activate NMDA channels, but you only need a tiny amount)

is keratitis acute or chronic visual loss?

chronic

is uveitis acute or chronic visual loss?

chronic

korsakoff's amnesic state

chronic alcoholism causes korsakoff's syndrome and depletes thiamine, an effect of which can be anterograde (and limited retrograde) amnesia.

fibromyalgia

chronic disorder characterized by widespread musculoskeletal pain, fatigue, and tenderness in localized areas - unknown cause

alzheimer's disease

chronic neurodegenerative disease which accounts for majority of cases of dementia; causes short-term memory loss, confusion, personality changes + loss of bodily functions (leads to death)

which kind(s) of pain are strong opiods not effective at treating?

chronic pain, eg neurological pain

complex regional pain syndrome

chronic systemic disease characterized by severe pain, swelling, and reddening/changes in the skin, affecting an arm/leg or entire body. worsens with time + may not have an obvious nerve lesion

which muscle changes shape of lens?

ciliary muscle

cisterna ambiens

cistern located on the lateral aspect of the midbrain

Class I afferent fibres from muscles/joints are the same as which class of sensory afferent fibres?

clas Aα

aripiprazole

class 3 antipschotic drug. DAD2 partial agonist. 5-HT1A agonist. 5-HT2A (hallucination) antagonist.

treatment for which disease consists of pupil constriction?

closed angle (acute) glaucoma

ventrolateral preoptic nucleus

cluster of neurons in anterior hypothalamus, involved in promoting sleep by *inhibiting the main components of the ascending arousal system

auditory nerve AKA?

cochlear nerve, acoustic nerve

what is the widely agreed best treatment for phobias?

cognitive behavioural therapy. (desensitization)

what is the paradoxical thermoreceptor response?

cold receptors usually increase their firing during cooling below 37oC, but some also respond with a brief AP discharge at high temps (>50oC)

cranial nerve nuclei

collection of neurons in the brain stem that are associated with one or more cranial nerves. sites of origin of motor fibres and termination of sensory fibres of cranial nerves

propriospinal tract

collections of nerve fibers, ascending, descending, crossed and uncrossed, that interconnect various levels of the spinal cord. located in white columns of the spinal cord, surrounding the grey matter

what information is not avaliable in parts of the visual cortex connected to the peripheral retina - but is to parts connected to central retina

colour

amiodarone

common antiarrhythmic, used to treat ventricular and supraventricular arrhymias, usually in acute management

vascular dementia

common form of dementia caused by an impaired supply of blood to the brain, such as may be caused by a series of small strokes

branch retinal vein occlusion

common retinal vascular disease of the elderly, caused by occlusion of one of the branches of central retinal vein

solitary tract

compact bundle that extends longitudinally through posterolateral medulla, surrounded by the nucleus of the solitary tract. descends to the upper cervical segments of the spinal cord. involved in taste, respiratory + cardiovascular system (chemoreceptors)

how does the cerebellum control movement?

compares info developed in the motor cortex (pontine nuclei) with sensory info from spinocerebellar tracts/vestibular system, then sends efferents to *contralateral* thalamus for *motor error correction*

therapeutic index

comparison of the amount of a drug that causes the therapeutic effect to the amount that causes death or toxicity. (higher is safer/more forgiving)

atropine

competitive inhibitor of muscarinic cholinergic receptors, used to decrease parasympathetic effects eg block the vagus suppression of the heartrate

adenosine

compound consisting of adenine combined with ribose, found endogenously and given as medicine to treat arrhythmia involving the AVN. acts on adenosine receptor to open K+ channels

list factors which influence the speed at which inhaled anaesthetics reach the brain

conc in inspired air, rate/depth of breathing, permeability of alveolar capillary membrane, blood flow through lungs, blood/air coefficient, blood flow to brain, partition coefficient between brain&blood of drug

4 examples of insults which can cause amnesia

concussion, chronic alcoholism (korsakoff's), tumours, stroke

heteroporia

condition where relaxed eyes point in different directions, eg a squint, resulting in poor convergence of images in both eyes (causes double vision when drunk)

what is the reciprocal of resistance?

conductance

blocking an ear with cotton wool simulates which kind of deafness?

conductive deafness

the free border of the falx cerebri lies above which cerebral structure

corpus callosum

which structure contains horizontal commissural fibres which unite the two cerebral hemispheres?

corpus callosum

which structure contains the caudate nucleus, putamen and globus pallidus?

corpus striatum

photorefractive keratectomy

corrective laser surgery. uses laser to reshape cornea + increase/decrease amount of refraction possible. not a permanent solution

cruciform axodendritic arrangement

cortical neurons tend to cross MSNs at right angles in such a way that each spiny neuron receives only 1-2 synapses from an individual cortical neuron

corticobulbar tract is aka?

corticonuclear tract

spectral notch

creases in the pinna which are the primary cues for the elevation of a sound

name the sensitive regions within the ampullae of the semicircular canals which can detect movements of endolymph as your head moves

cristae

from their source, do spinothalamic tracts ascend on ipsilateral or contralateral side of the spinal cord

cross when enter spinal cord and ascend contralaterally to thalamus

what colour is healthy CSF

crystal clear

where do the two levels of the dorsal column medial lemniscus pathway supply?

cuneate fasciculus carries info from T6 and above, gracile fasciculus carries info from T7 and below

what do EEG brainwaves look like during a seizure?

cycle of high amplitude, mid-frequency 'spike' followed by a 'slow wave'

fasciculus cuneatus

lateral pathway of dorsal column of spinal cord; carries tactile sensation + vibration + proprioception *from the upper limb* to the *cuneate* nucleus in the medulla

lateral vestbular nucleus is source of which tract?

lateral vestibulospinal tract

corticospinal neurons arise from which layer of neocortex

layer 5

which layer of the primary motor cortex do pyramidal neurons originate in

layer 5

retina

layer of bran tissue back of the eyeball containing cells that are sensitive to light and that trigger nerve impulses that pass via the optic nerve

claustrum

layer of gray matter; linked to consciousness and has connections to all over the neocortex

is wernikes area more dominant on left or right

left

where in the brain is the language area?

left cerebral hemisphere in regions of frontal/parietal/temporal lobes next to the *lateral fissure*

which area of the visual field is viewed by the right hemisphere of the brain?

left visual hemi-field

cataract

lens becomes clouded/yellow so you see a darker, blurry image. more common in elderly. may be due to UV light.

which artery supplies posterior limb of internal capsule

lenticulo-striate arteries

what could cause bi-temporal hemianopia?

lesion at the decussation of optic nerves

why does a wheelchair patient have average BP of around 60-80mmHg?

lesion in cervical spine leads to lack of sympathetic tone

what are the effects of a PICA lesion

lesion leads to *lateral medullary syndrome*; loose pain + temp sensation on ipsilateral side of face and contralateral side of body

cerebellar syndrome

lesions in cerebellar pathways lead to poor error correction in movements - patient shows incoordinated eye movements, speech movements, intention tremor and ataxia (all visible *ipsilateral* to lesion)

which absorbs faster, more or less soluble anaesthetics? why?

less soluble, because less soluble agents like NO2 have a higher MAC so it is safe to deliver more into the lungs faster

spinothalamic tract decussate at the medulla or the level of spinal cord?

level of spinal cord

Type II sensory fibres function

lie within muscle and fire *when muscle is static*

reye's syndrome

life-threatening metabolic disorder in children, of uncertain cause but linked to recenet acute virus (influenza/varicella) and aspirin. causes rash, vomit, fatty liver and encephalitis

HM could form fairly good memories of pictures he'd seen. why?

likely because he still had about 2cm of perirhinal cortex left

activity of which brain system correlates to rated pain intensity reported in chronic pain?

limbic system

what and where is there (more) pooling of photoreceptor signals?

linking up of signals from rods and cones to increase signal strength (at the cost of lower resolution).

why is white matter darker than grey matter on CT scan?

lipid containing material is radiolucent (transparent to x-rays)

what single feature is common to all anaesthetics

lipid solubility

kinocilium

literally a long 'eyelash' found on the apex of inner ear hair cells; plays role in opening K+ channels on sterocilia and detecting body movements

supplementary motor cortex

located anterior to primary motor cortex leg representation. projects to spinal cord and becomes active bilaterally when you simply *think* about moving.

calcarine sulcus

located at the caudal end of the medial brain surface. important because it has visual function (peripheral vision at its anterior end, central vision at its posterior end)

fusiform face area

located in the fusiform gyrus (Brodmann area 37). becomes more active when looking at faces; helps you identify people by face. active on in both hemispheres but the R side is most damaging to lose

in which part of the night is your deepest sleep?

early in the night, within first couple hours of sleep

ectopic foci

ectopic pacemaker; regions outside the SAN which start acting as pacemakers, often causing problems

damage to which parts of the diencephalon disrupt memory?

either *anterior* or *dorsomedial* nuclei of the thalamus, or the *mammillary bodies* of the hypothalamus

what are the indications for angiography

either diagnostic: rupture/haemorrhage or occlusion/ischaemia. or therapeutic uses: modified interventional catheters

what does 'fasciculation' mean?

either: being arranged in bundles (fascicles) OR spontaneous ripple like contraction of muscle beneath the skin, due to lower motoneuron damage

who would you expect listeria monocytogenes to cause meningitis in?

elderly (>55 yrs), pregnant, neonates, or immunosuppressed

resting potential

electrical potential of a cell (relative to its surroundings) when not involved in passage of an impulse

lhermitte's sign

electrical sensation that runs down the back and into the limbs upon neck flexion. linked to several conditions, classically MS

EEG

electroencephalogram: use 21 scalp macroelectrodes to produce a graphical record of electrical activity of the brain

EOG

electrooculograph. electrodes placed above/around eye are used for measuring resting potential of the retina in ophthalmological diagnosis and in recording eye movements

how can we learn about the function of extra striate cortex?

electrophysiological studies on animals/patients. anatomy and histology, tracer studies etc. imaging studies (fMRI, PET, etc.) patient case histories accompanied by imaging studies or post mortem histology

why are strokes in striate arteries common?

emboli carried up the carotid tend to sweep into the MCA and be trapped in the striate artery branch point of the sylvian fissure

what is the main treatment for AVM

embolisation (cutting off the blood supply with coils or glue) + surgery

why do we need seperate efferents to intrafusal (gamma) and extrafusal (alpha) muscle fibres?

enables tightening intrafusal fibres a bit more than extrafusal fibres - advantageous as it puts spindle in a more dynamic range (useful for very fine movements)

which key molecules are responsible for much of the bodies 'toning down pain' responses

endogenous opiate peptides

enkephalin and dynorphin are examples of what

endogenous opiod neurotransmitters (involved in endogenous descending pain modulation)

neurosteroid

endogenous or exogenous steroids that rapidly alter neuronal excitability through cell surface receptors. some have potential as treatment for epilepsy/anaesthetics

which are the first muscles to be noticeably affected by parkinsons disease?

facial muscles

which lense corrects hyperopia?

farsightedness can be corrected with convex lenses

saccade

fast, simultaneous movements of both eyes in the same direction. can be under voluntary control

will a base with lower pKa have a faster or slower onset? why?

faster onset - lower pKa means a greater fraction of molecules exist in the uncharged form, so more can cross the lipid membrane of nerves at a time

is meningioma more common in males or females?

females

name the processes which shoot dynamically in and out of axon growth cones, detecting chemicals which direct axon to its target?

filopodia

damage to the corticospinal tract doesn't actually prevent most movements (other tracts can take over) EXCEPT FOR WHAT?

fine movements, eg of the hands

microneuronography

fine tungsten needle electrode is inserted through skin into peripheral nerve, and connected to a high gain recording amplifier

Broca

first scientist to discover that there are parts of the brain specialised in different functions; found and named an area involved in language

at which end of the cochlear is the basilar membrane fixed, and which end is it free to move?

fixed at the base of cochlear, free to move at the apex

which are found nearer the central canal, the motor neurons of flexor or extensor muscles?

flexor

syrinx

fluid-filled cavity which forms in the central spinal cord (usually cervical spine)

why is blue light often used to examine front of eye?

fluorescein dye will be uptaken by any breaches/abrasions in corneal epithelium - this orange dye reacts to blue light.

refractive power (of the eye) = reciprocal of what?

focal distance

what are the 'plaques' in MS

focal lesion where myelin sheaths gets lost, and brain attempts to remylinate (but fails). an oedema or buid up of astrocytes may also form due to surrounding neuron destruction

which brain area(s) are most involved in classical conditioning?

for conditioning involving emotional responses, the amygdala. if involving skeletal musculature, is the cerebellum.

name the foramen directly below superior orbital fissure

foramen rotundum

is the thalamus in forebrain or midbrain?

forebrain

prosencephalon

forebrain; develops from anterior neural tube. forms telencephalon and diencephalon

frontal eye fields

found at bottom of middle frontal gyrus. responsible for non-tracking, voluntary movements of the eye

where is the one part of the retina where cones outnumber rods?

fovea

which area has the highest density of cones in the eye?

fovea

what does frequency and amplitude of a light wave determine?

frequency determines hue, amplitude determines brightness

what does '20/20 vision' mean?

from 20ft away, you can read up to the designated '20 foot' line of letters on a snellen chart. (eg worse vision would be 20/50, better vision 20/10)

how might tinnitus originate from within the body?

from a blood vessel near the ear having abnormally fast/turbulent blood flow (think atherosclerosis, anemia, pregnancy)

how does the basilar membrane change along its length?

from base to the apex of cochlea: becomes wider, less stiff, heavier, measures lower sounds

where does the internal carotid arise?

from common carotid in the neck, at around C4/chin height

where do microglia cells originate?

from perivascular space or monocytes

Spino-parabrachial pathway carries fibres from where to where? what is itsgl function?

from the spine to parabrachial nuclei of the brain, to respond to nociceptive inputs

where do the vertebral arteries arise

from the subclavian arteries, posterior in the root of the neck

how is the basilar artery formed?

from the two vertebral arteries joining

are you likely to have huntingtons earlier if you inherit it from your mum or your dad?

from your dad

primary motox cortex is in which lobe?

frontal

beta rhythms are particularly seen in which regions of the brain?

frontal and parietal

motor neuron disease is often linked to which form of dementia?

fronto-temporal lobe dementia

what part of the eye does the opthalmoscope illuminate?

fundus (the back of the eye, including retina, optic disc, macula, fovea)

what is the far point of your vision

furthest point at which you are able to bring an object into clear focus (for healthy eyes, this is *infinity*

efferent innervation to muscle spindles is carried by which fibre type?

gamma motor neurons

which are the only cells in the retina to produce action potentials?

ganglion cells

mamillary body is important for?

generating new memory (depletes in people with thiamine deficiency eg alcoholics)

drosophilia

genus of small flies, often called fruit flies

how do meningitis bacteria infect their way into subarachnoid space?

get through nasal mucosa, into bloodsteam, and through blood brain barrier into subarachnoid space where they multiple rapidly

Betz cells

giant pyramidal cells located within primary motor cortex, that give rise to *corticospinal tract*

which scale assesses the degree of coma?

glasgow coma scale

what are the 3 main responses measured in the GCS?

glasgow coma scale measures: eye opening response, verbal response, motor/pain response

oligodendrocyte

glial cell similar to an astrocyte but with fewer protuberances, concerned with the production of myelin in the CNS

satellite glial cells

glial cells that cover the surface of nerve cell bodies in sensory, sympathetic and parasympathetic ganglia. supply nutrients, protection, and control over the microenvironment of the ganglia (similar role to astrocytes in CNS)

proliferation of glial cells is called

gliosis

what is the main output nucleus of the basal ganglia? where do these fibres go?

globus pallidus, inhibitory fibres to the thalamus

cone cells always have which neurotransmitter?

glutamate

is cortical drive into basal ganglia glutamate or gaba?

glutamate

what is the most abundant neurotransmitter in the nervous system?

glutamate

what is GAD

glutamate decarboxylase. enzyme which converts glutamate to GABA in a single step

GTN

glyceryl trinitrate: explosive yellow liquid in dynamite and also medicine as a vasodilator in the treatment of angina pectoris

which stain is best used to view neurons?

golgi stain (can see individual cells not just pink+purple mass)

diffuse astrocytoma

grade II brain tumour originating in astrocytes; tends to invade surrounding tissue and grow at a relatively slow pace

schild plot

graph constructed from dose-effect curves and dose-ratios which can be used to work out the PA2 of a competitive antagonist

concentration-response curve

graph showing how increasing the concentration of a substance (drug?) affects a functional response of a tissue; aka dose-response curve

audiogram

graph that shows the audible threshold for an individual as measured by an audiometer (hearing test machine).

how does hippocampal amnesia affect ability to imagine new experiences?

greatly reduces the richness/detail of imaginations compared to normal people. (to do with poor episodic memory. same areas involved in remembering past also involved in imagining future; you need to remember the past to do this)

is cerebral cortex white or grey matter?

grey

is the cerebellar cortex made of white or grey matter?

grey

is the thalamus comprised of white or grey matter?

grey

which contains more synaptic networks, grey or white matter?

grey (white matter structures are devoid of synaptic networks)

parahippocampal gyrus

grey matter cortical region of the brain that surrounds the hippocampus, important in memory encoding and retrieval

how can you instantly tell which way 'up' a transverse section of spinal cord is?

grey matter is always fatter *anteriorly*

periaqueductal grey

grey matter located around the cerebral aqueduct within the midbrain. forms the primary descending analgesic pathway from cerebral cortex (has enkephalin-producing cells that suppress pain)

name the cells which fire action potentials when an animal passes through a specific small region of space

grid cells and place cells

ventral medial fissure

groove along midline of anterior surface of spinal cord + medulla

lymphoma

group of blood cell tumors that develop from lymphatic cells; usually malignant. Relatively treatable

clarke's column

group of interneurons found in the medial part of Lamina VII of the spinal cord, mainly from T1 to L3 levels. important for proprioception (transmits spinocerebellar tracts)

clarkes column

group of interneurons found in the medial part of Lamina VII of the spinal cord. It is mainly located from the T1 to L3-L4 levels and is an important structure for proprioception

nucleus basalis of Meynert

group of neurons below globus pallidus in basal forebrain. has wide projections to the neocortex/fornix. involved in vision perception, ACh + intelligence/learning

where are more neurons - gut or spinal cord?

gut

gyri VS sulci

gyri are the bulges and sulci the furrows between them

what kind of hair cells are found in the organ of corti?

hair cells; 3 rows outer hair cells (notably sensitive to damage) and 1 row inner (release NT onto auditory nerve fibres)

difference between hallucination and delusion

hallucination is an experience of perceiving/sensing something that is not present. delusion is a fixed false belief which the person believes despite all evidence

mescaline

hallucinogenic and intoxicating compound present in mescal buttons from the peyote cactus

which general anaesthetic causes liver damage

halothane

function of the auditory canal

has wax to protect from insects and hairs to keep a constant temperature. also serves to amplify sounds around its resonant frequency (2,000-5,000 Hz)

ototoxic

having a toxic effect on the ear/ its nerve supply

the anterior limb of internal capsule divides which structures?

head of caudate nucleus and putamen/globus pallidus

the superior and inferior colliculi contain reflex centres involved in what?

hearing and vision (they used to be the main hearing/vision centres until cerebrum evolved into a higher system)

cochlear implant

hearing device which replicates "frequency-to-place" mapping of basilar membrane, replacing hair cells by stimulating the auditory nerve at different frequencies

why might tinnitis onset with hearing loss?

hearing loss can lead to phantom sounds, indicating that tinitis may be caused by reduction of auditory input, not cochlear damage.

Rinne's test

hearing test, evaluates loss of conductive hearing in external/middle ear. compares perception of sounds transmitted by air to those transmitted by bone through the mastoid. negative (abnormal) response: bone conduction heard longer than air

name the 4 pharmacological target organs of antihypertensive drugs

heart, vasculature, autonomic nervous system, and kidneys

difference between hemispatial neglect and homonymous hemianopia

hemianopia is a lesion earlier in the visual pathway - you don't *see* half the visual field. hemispatial neglect is more cognitive - you can see everywhere but just *ignore* half

transtentorial herniation

herniation of the medial temporal lobe from the middle into the posterior fossa, across the tentorial opening; compresses oculomotor nerve on same side

dendritic eye lesions on surface of cornea are characteristic of which disease?

herpes simplex keratitis

strabismus is AKA

heteroporia

do inner hair cells produce a DC response at high or low frequencies?

high

how is the glasgow coma scale scored?

higher score = greater responses. score of <8: coma, 9-12: moderate head injury, >12 mild head injury (max score is 15)

where is the huntingtons gene located?

highest tip of chromosome 4

rhombencephalon

hindbrain; develops from neural tube. forms metencephalon and myelencephalon

which structure in the brain is classically associated with the *formation of new* memories?

hippocampus

brodmann area 28 provides the principal excitatory drive for which brain area?

hippocampus (area 28 = ventral entorhinal cortex)

which 2 brain structures are affected first in alzheimers disease?

hippocampus and posterior parieto-temporal cortex

which is more associated with conditioning and which with declarative knowledge, hippocampus or amygdala?

hippocampus with declarative knowledge, amygdala with conditioning.

where in the brain do neurofibrillary tangles form initially? where do they progress to?

hippocampus/entorhinal cortex at first, progressing to limbic system before then affecting the rest of the brain

spatial memory is particularly located in which part of the brain?

hippocampus; it has 'place cells' which encode location in the environment

post-stimulus time histogram

histograms of the times at which neurons fire. used to visualize the rate and timing of neuronal spike discharges in relation to an external stimulus. different nerve cells have different PSTHs

3 categories of OCD

hoarders/collectors, ritual checking behaviour, cleanliness

what travels through the transverse foramina?

holes in the transverse processes; give passage to the *vertebral artery, vein and sympathetic nerves*

uncus

hook-shaped process or part; particularly the anterior extremity of the Parahippocampal gyrus: part of the limbic system involved in olfaction

which cells pre-process information from rods and cones before sending it to the optic nerve?

horizontal, bipolar, amacrine and ganglion cells (retinal interneurones)

what is HRP

horseradish peroxidase. enzyme which can be used to label single cells, eg neurons in their entirity

treatments for dry eyes

hot compress + lid cleaning - stimulates oil production/good quality tears

how do you treat blepharitis

hot compresses and scrub base of eyelid with damp cotton buds

what is a key function of periaquital grey

houses a descending analgesic pathway, involving enkephalin-producing cells that suppress pain by releasing endogenous opiods

describe the dendrites of purkinje cell

huge dendritic tree which is very spead out but completely flat (like your fingers branching from your hand)

Natalizumab

humanized monoclonal antibody against the cell adhesion molecule α4-integrin, used to treat MS and Crohn's disease. prevents rolling/binding of immune cells to vessel wall in intestines and BBB, so they are less able to enter gut lining/CSF

describe what you might expect to see if you clinically examined the gait of someone with parkinsons

hunched over, sway side to side, small shuffling steps, difficulty starting and difficulty stopping once moving

which proteins aggregate in huntingtons disease?

huntingtin

enlarged lateral and 3rd ventricles, without enlarged 4th ventricle, suggests what?

hydrocephalus caused by an obstruction between 3rd and 4th ventricle - perhaps cerebral aquaduct

do anaesthetics bind to hydrophilic or hydrophobic domains of proteins?

hydrophobic

what are the adrenal gland causes of 2ndary hypertension?

hypermineralcorticoidism, hyperglucocorticoidism, phaeochromocytoma

do lower motoneuron lesions lead to hyper or hyporeflexia?

hypo

are dark structures on a CT hyper or hypodense

hypodense

which DA pathway is related to the negative symptoms of shizophrenia

hypofunction of mesocortical pathway

adverse effects common to all class I antiarrhythmic agents

hypotension, nausea, vomiting

which part of the brain can inhibit normal baroceptor reflexes during 'fight or flight' ?

hypothalamus

which part of the diencephalon is involved in the autonomic NS, limbic system, and neuroendrocrine system?

hypothalamus

which higher centres (in the brain) are involved in autonomic control?

hypothalamus, forebain, amygdala, hippocampus etc

what is the key area for coordinating autonomic nervous system responses in the brain? how?

hypothalamus. it projects to key ANS areas eg the NTS, the parasympathetic nuclei in the medulla, the rostroventral lateral medulla and preganglionic sympathetic neurons in the spinal cord

the monoamine hypothesis of depression

hypothesis that "depression is a deficit of monoamine transmission, and antidepressents stop monoamine transmission"

standard consolidation theory

idea that Hippocampus + related MTL structures are initially required for episodic memory storage and retrieval, but after time, these areas are less involved and cortex is able to retrieve memory without hippocampal help

multiple trace theory

idea that although connections to the cortex grow with time, hippocampus mediates storage + retreival of episodic memories for entire life, not just before the memories have been consolidated

in memory, how might the sight and smell of a rose become linked?

if a neuron receives input for both the smell and sight of a rose (often activated *together*) and these inputs *summate* to activate the neurone and create an LTP

astigmatic fan

if any lines look blacker than the rest - and the blackest lines change as you rotate your head around an anterior-posterior axis - indicates astigmatism

does paired stimulation of parallel fibres and climbing fibres on purkinje cells lead to long term *depression* or *potentiation* and why?

if both are active, climbing fibre increases Ca levels in purkinje cell, and parallel fibre increases protein kinase C. together, these react to phosphorylate AMPA receptors which *in purkinje cells only* decreases AMPA receptors

how can a weak input undergo long term potentiation?

if it coincides with postsynaptic depolarization caused by a strong input, or another weak input which summates. (this makes the LTP *associative*)

the axon reflex

if stimulation onto skin is so severe as to damage skin, this is fed back by collateral nerves which release substance P - causes mast cells to release vasodilatory and inflammatory peptides around the site

why does boosting the amplitude of sound vibrations in the ear result in narrower tuning?

if theres a higher amplitude in response to same sound, there is a narrower peak, resulting in narrower tuning

why might you get *referred* phantom limbs?

if you lose a hand for example, the next areas on the homunculus may branch to where the hand used to be 'felt' in the somatosensory cortex

which drug is regarded as the gold standard in terms of efficacy in antidepressants?

imipramine (a TCA)

when does inflammation occur in the absence of infection?

immune disorders, atherosclerosis, trauma, ischaemia

associative visual agnosia

impairment in recognition or assigning meaning to a stimulus that is accurately perceived. patients can copy drawings but not identify objects they've drawn. not associated with a generalized deficit in intelligence, memory, language or attention

functions of middle ear

impedance matching, selective oval window stimulation, pressure equalisation. transfer sound from air (tympanic membrane) to fluid (oval window)

why is the internal capsule clinically revelant?

important site of stroke (subsequently called a capsular stroke). all descending motor fibres pass through posterior limb of internal capsule

what are the aims of pain treatment

improve control of pain, reduce disabling effects with short + long term goals, build a realistic model of problem to reduce catastrophising, aid friends and family

descartes

in 1600s came up with idea of 'dualism' - that the mind and the brain depend on each other, but are separate.

difference between bipolar and unipolar EEG recording

in bipolar, the voltage difference between a pair of electrodes is measured. In the unipolar, the potential of each electrode is compared either to a neutral electrode or to the mean voltage of all electrodes

give 2 conditions in which pupil healthily dilates

in dark (raising sensitivity) and in excitement (sympathetic system)

why do demyelinated plaques tend to look darker than healthy grey matter?

in healthy grey matter, there are still myelinated neurons projecting through it from the white matter

do on center bipolar cells depolarise or hyperpolarise in light? how about in dark?

in light, they depolarise, in dark, they hyperpolarise

why can you see colours better in brighter light?

in low light, only rods are sensitive enouge to see with; cones won't fire hence can't see colours

why does the volume ratio of white to grey matter change at different spinal cord levels?

in lower regions there is more grey matter and less white, because there are fewer ascending/descending tracts

where is visual cortex located

in occipital lobe, mostly medial hemisphere above and below the *calcarine sulcus*

how do EEGs differ when neurons are firing irregularly or in sync?

in sync has larger amplitudes and slower frequencies - like when asleep

where is auditory cortex located

in temporal lobe, beneath and parallel to lateral fissure in the *superior temporal gyrus*

where does the dorsal-column medial lemniscus pathway decussate?

in the medial lemniscus tract (between the dorsal column nuclei and the thalamus) at around the level of the medulla

in which part of the CNS does the corticospinal tract break up into many bundles (rather than one bundle on each side)

in the pons

where are most of the proteins made in a neuron?

in the soma (processing centre)

why is there increased risk of overdose if a heroin user takes heroin in an unfamiliar environment

in their normal setting, the user has their normal tolerance. in new settings, they may have no such tolerance

constructional apraxia

inability or difficulty to build, assemble, or draw objects

anterograde amnesia

inability to *make or retrieve* new memories *after* the trauma

anhedonia

inability to feel pleasure

agnosia

inability to recognize/perceive objects by use of the senses, due to brain damage in tempoparietal cortex

augment

increase

do antidepressants increase or decrease neurogenesis in hippocampus

increase

does angiotensin increase or decrease BP?

increase (by vasoconstriction and fluid retention)

what is the effect of nitrous oxide and ketamine on sympathetic outflow?

increase it

class II antiarrhythmic agents

increase the period of the pacemaker cycle by antagonising Beta sympathetic activity. this group includes beta blockers

hyperalgesia

increased sensitivity/reactivity to *painful* stimuli, which may be caused by damage to nociceptors or peripheral nerves, or temporarily by sickness/stress

describe how urine storage requires both autonomic NS and somatic motor NS?

increased sympathetic activity inhibits parasympathetic contraction of the bladder smooth muscle (the detrusor) - enables bladder to expand. simultaneously, sympathetics + somatomotors increase bladder neck contraction + skeletal muscle of urethral sphincter respectively - maintains continence.

does D2 antagonism increase or decrease prolactin levels

increases (tuberoinfundibular pathway)

why does parkinsons treatment often induce new addictive behaviours?

increases dopamine in mesolimbic/nucleus accumbens/ventral tegmental area (involved in reward system)

what happens to the human sleep/wake cycle if environmental cues (light/temp etc) are removed?

increases from 24 hr cycle to up to 36hr cycle (physiological functions may not keep in step though)

3 functions of dopamine in the brain

increases motor aspects of basal ganglia, activates euphonia + cognition of brain, and inhibits prolactin release

why is catastrophising so detrimental to pain recovery?

increases pain intensity, predicts chronicity and disability developing from acute pain, and predicts mood/behaviours in chronic pain

does digoxin increase or decrease the heart?

increases strength of contraction but decreases AV conduction rate

why is a bit of anxiety good for you?

increases vigilance

when inhaling anaesthetics, which increases rate of equilibrium - increasing or decreasing rate+depth of respiration? why?

increasing. it increases rate of equilibration between alveoli and blood

which passes through the globus pallidus externa, the direct or indirect pathway?

indirect

which basal ganglia pathway degenerates faster in huntingtons disease?

indirect (hence you struggle to *inhibit unwanted movements*)

which colliculus do almost all ascending auditory pathways go through?

inferior colliculus (integration centre)

which cerebellar peduncle contains fibres from the spinocerebellar tract? what do they carry?

inferior peduncle. carry info from joints and muscles to cerebellum

keratitis

inflammation of the cornea causing watery painful eyes and blurred vision

blepharitis

inflammation of the eyelids caused by chronic staphylococcal inflammation; characterized by redness, burning, itchiness blurring, swelling and dried crusts/oily secretions on lids

optic neuritis

inflammation of the optic nerve. causes painful loss of vision

uveitis

inflammation of the uvea, the middle, pigmented, vascula layer of eye (including choroid/iris/ciliary body). causes painful visual loss

two main types of pain

inflammatory and neuropathic

what is memory priming?

influencing what thoughts you withdraw from their memories in a non-conscious way by what has happened to you recently - eg product placement.

What type of sensory information does the spinothalamic tract carry ?

info about pain, temperature (lateral pathway) itch and crude touch (anterior pathway)

two main categories of general anaesthetics

inhalation agents (vapour or gas), and intravenous agents

aside from intravenous agents, general anaesthetics can be administered as what?

inhalation agents, which are either *gases* or *volatile liquids*

does glutamate inhibit or stimulate on-centre bipolar cells?

inhibit (hence they fire more in the light)

how do opiates release pleasure in the brain?

inhibit GABA inhibitory neurons connected to dopaminergic neurons in nucleus accumbens - disinhibition

how do ACE inhibitors decrease blood pressure?

inhibit the pulmonary conversion of angiotensin I to angiotensin II, hence reduce the vasconstrictive a ects of angiotensin II. also decrease the resorption of Na+ & water in PCT

in general, do activated alpha and beta 2 receptors have excitatory or inhibitory effects?

inhibitary

in stretch reflex, which muscles *aside from the homonymous muscle* may also be affected?

inhibitory GABAergic neuron can project to *antagonist muscle* to block it. other motoneuron may project to *synergist muscle*

renshaw cell

inhibitory interneurons found in the gray matter of the spinal cord. provide a regulatory feedback system to prevent rapid repeat firing of motor neurons

what is IPSP

inhibitory post-synaptic potential. synaptic potential that makes a postsynaptic neuron less likely to generate an action potential, due to postsynaptic influx of anions causing hyperpolarisation

anti VEGF injections

injected drugs which reduce new blood vessel growth or oedema (swelling), often used in wet age-related macular degeneration/eye conditions which cause fluid to leak under the retina

what is the only example of where drugs acting on the CNS can be *given locally*

injecting morphine straight into spinal cord to target its receptors

which ear hair cells function to transmit info to the brain via auditory nerve?

inner hair cells

are the hair cells in the organ of corti passive or active?

inner hair cells are *passive* and outer hair cells are *active*

how do IHCs perform *mechano-electrical transduction*

inner hair cells, in response to basilar membrane vibration, release neurotransmitter onto synapses of auditory nerve fibres

long term depression

input-specific reduction in the strength of neuronal synapses lasting following a long low frequency tetanus. (low Ca2+ levels in postsynaptic neuron decreases AMPA receptors)

corticopinal pathway has inputs onto which neurons in the stretch reflex?

inputs the Ia inhibitory interneuron, and the motoneurons to the homonymous muscle

aneurysm coiling

inserting a coil into aneurysm via catheter. fills the aneurysm with coils so that blood can't enter it - prevents it growing or rupturing

hypnotic drugs are used to treat which condition?

insomnia (hypnosis is greek for sleep)

non-associative learning

instances in which an animal's behaviour toward a stimulus changes in the absence of any apparent associated stimulus or event (such as a reward or punishment)

insula

insular cortex is a portion of the cerebral cortex in each hemisphere, folded deep within the lateral sulcus. has somatosensory + taste area. middle cerebral artery runs through here

amyloid precursor protein

integral membrane protein expressed in many tissues and concentrated in the synapses of neurons. can cause protein deposits if excessively cleaved by secretases

what are the ideal psychological models of pain

integrated biopsychosocial models

neuralgia

intense, typically intermittent pain along the course of a nerve, usually caused by central/ peripheral neuronal injury

the sclera is continuous with what?

interiorly with the choroid, externally with the dura of the CNS, anteriorly with the cornea

cauda equina compression

intervertebral disc prolapse/tumour compresses cauda equina. damages important nerves like S2,3,4 - causes bladder, anus and erectile dysfunctions

intracranial space occupying lesions

intracranial lesion usually due to malignancy (though can be caused by an abscess or haematoma). resulting raised ICP can cause internal herniation

which causes more rapid general anaesthesia, inhaled or intravenous agents?

intravenous (causes unconsciousness in about 20s - as soon as drug reaches brain - rather than a few minutes)

difference between intrinsic and extrinsic lesions of nervous system

intrinsic are within nervous system, extrinsic lie outside and compress the nervous system. extrinsic lesions are more likely to be remediable by neurosurgery

brudzinskis sign

involuntary flexion of the hips in response to passive flexion of the neck; indicative of meningeal irritation

what is the time difference between transmission with ionotropic + metabotropic receptors?

ionotropic is rapid <<1ms, whereas metabotropic much slower: >50ms

what are monovalent cations

ions with a charge of +1, eg Na+ and K+

is the vestibulospinal tract ipsilateral or contralateral

ipsilateral

are lower moto neuron lesion effects ipsilateral or contralateral to the lesion?

ipsilateral (lower motoneurons innervate muscles on same side as their cell bodies)

dorsal spinocerebellar tract

ipsilateral tract involving two neurons which conveys proprioceptive information from skeletal muscles to the cerebellum, via Clarkes column

does the cerebellum coordinate movements on the ipsilateral or contralateral side of the body?

ipsilateral. its efferents decussate on way to motox cortex, and fibres from the cortex (eg corticospinal tract) decussate again, back onto same side.

agoraphobia

irrational fear of crowded spaces or enclosed public places

catastrophizing

irrational thought a lot of us have in believing that something is far worse than it actually is

iproniazid

irreversible nonselective MAO inhibitor

disadvantages of propofol

irritant at site of injection

can neuropathic pain be treated?

it can be poorly controlled by drugs like tricyclic antidepressants/ gabapentin/pregabalin, with disabling side affects such as confusion

does the enteric nervous system work in isolation from the CNS?

it can, but it gets many inputs from autonomic NS etc which may override it - symp decreases and parasymp increases enteric activity

how does light affect neurotransmitter release from photoreceptors

it decreases glutamate release by *hyperpolarising* them

how can aripiprazole act as an antipschotic when it is a D2 agonist?

it is a *partial* agonist of DAD2 receptors - competitively decreases action of dopamine overall even though it has a small agonist effect itself

why is the cornea the only body part that can be transplanted between people without risk of rejection from new body?

it is avascular, so escapes the immune systems careful watch

how is codeine so weak if its a pro-drug for morphine

it is converted into morphine in the body, but this is usually slow (depending on enzymes you have). codeine itself can't bind to opioid receptors

what are memories made of?

it is widely agreed that they are alterations in synaptic strength, involving long term associations and long term depressions

why might pain prevent you getting opiod addiction?

it may inhibit the reward pathway which would have made you addicted (could help explain why there are few addicts after hospital use)

how does myelin save ATP energy needed in axons?

it prevents the whole axon being influxed with Na+ (during an AP) and needing to be pumped out to 'reset'. instead, this depolarisation + pumping out is only needed at nodes of ranvier

why is prestin important in outer hair cells

it responds to sound by contracting, changing the shape of OHCs to *amplify/sharpen* the soundwave travelling in the basilar membrane (improves audible threshold and distinguishing different frequencies

why is ketamine used as an anaesthetic in those with asthma/COPD and in war zones?

it suppresses breathing much less than other anaesthetics - good in those with previous breathing problems/in places with no ventilator

how can a single neuron contact another neuron more than once?

its axon may have multiple boutons to connect with multiple dendrites

why isn't motor cortex mapping that acurate. why is this a good thing?

its not a simple 1:1 projection - there is overlap + plasticity between areas. means is easier for stroke victims etc to retain some functions around body

hemiballismus

jerky movements of upper limb on contralateral side of body, like throwing a ball. caused by subthalamic nucleus lesion

which other receptors aid the joint

joint receptors, cutaneous receptors, pain endings within the muscle itself

what are the 6 universally recognisable facial expressions?

joy, fear, disgust, sadness, surprise, anger

vagus nerve leaves the skull through which foramen?

jugular foramen

in unipolar EEG recordings, where might you place the macroelectrode to pick up a 'neutral' reference voltage

just behind the ear (there is not much brain below that part of scalp)

which consonant sounds are in the high frequency range of hearing?

k, f,s,th

how do you convert between degrees C and kelvin?

kelvin = celsius + 273

where do unmyelinated axons travel in spinal cord?

kind of anywhere; but most often in the white matter with myelinated axons

cerebellar ataxia

lack of voluntary coordination of muscle movements (eg gait abnormality) caused by cerebellar damage eg tumour/infection/hereditary disorders

decerbrate

lacking cerebral brain function, as by having the cerebrum removed/its blood supply cut off

nissl substance

large granular body found in neurons for protein synthesis. useful for staining (cresyl violet stain) as they are found mainly in cell soma not axons

inferior olivary nuclei

largest nuceli in the olivary body, part of the medulla. major input to cerebellum, providing climbing fibres

short-term memory

lasts for a few minutes, usually involves mental rehearsal and is easily disturbed (e.g. the initial stages of learning a telephone number)

tardive

late-occurring (especially with reference to symptoms of a disease)

what does lateral light and medial music mean?

lateral geniculate nuclei are for vision, medial geniculate nuclei are for auditory

what is the LGN?

lateral geniculate nucleus. small, ovoid, ventral projection at the termination of optic tract on each side of the brain; relay center in the thalamus for the visual pathway

how does occlusion of PICA manifest?

lateral medullary syndrome (due to ischaemia of lat. medulla). sensory deficits in ipsilateral side of face, and contralateral side of body

PICA stroke symptoms are also called what?

lateral medullary syndrome or wallenberg syndrome

dorsal lateral medullary syndrome

lateral part of the medulla oblongata infarcts due to vertebral artery/PICA occlusion. ipsilateral loss of pain/temp from face, and contralateral loss of pain/temp from rest of body. may also have vestibular nucleus damage (vomiting/falling)

korsakoff's syndrome

serious mental illness, typically the result of chronic alcoholism, characterized by disorientation and a tendency to invent explanations to cover a loss of memory (confabulation)

which genes are likely to be affected in heritable depression

several genes of small effect, involved in eg serotonin transporters. environmental factors interact with these

agranulocytosis

severe deficiency of granulocytes in the blood, causing increased vulnerability to infection

craniorachischisis

severe form of neural tube defect in which both the brain and spinal cord remain open to varying degrees. most babies are stillborn

define *malignant* hypertension

severe hypertension with clinical features (e.g. headache, confusion, retinopathy). medical emergency.

corona radiata

sheet of white matter in branching into each hemisphere contains both descending and ascending axons. carries nearly all neural traffic from and to the cerebral cortex. concentrates itself as *internal capsule* deep inside hemisphere

crossed pupil reflex

shining light into *only one eye* will constrict *both* eyes

uses of nitrous oxide

short acting analgesic, carrier gas with stronger anaesthetics, can be used in pregnant women to relieve pain

class IV antiarrhythmic agents

shorten the plateau phase of cardiac action potential by blocking calcium channel blockers; slows AVN conduction.

flashing a light into one eye will contract one or both pupils?

should contract both (failure of either eye indicates lesions in the pupillary reflex pathway

how does the overall appearance of the brain change in alzheimers disease?

shrinkage of the forebrain + expansion of the sulci and ventricles as the brain tissue is lost

in brown-sequard syndrome, which side do you lose sense of proprioception on and why?

side ipsilateral to the lesion - because the dorsal column (carries proprioception) ascends ipsilaterally, whereas spinothalamic ascends contralaterally

striatum is said to be involved in what type of memory?

skills and habits (part of implicit memory)

glabrous skin

skin devoid of hair

acne rosacea

skin disease of adults (more often women) in which blood vessels of the face enlarge resulting in a flushed appearance

cutaneous mechanoreceptors

skin receptors which respond to mechanical stimuli from physical interaction eg pressure and vibration. Are all innervated by Aβ fibers, except the mechanorecepting free nerve endings, which are Aδ

mechanism of action of N2O?

slightly blocks NMDA (causes dopamine release/euphoria) and β2-subunit-containing nACh channels. weakly inhibits AMPA, kainate, GABAC, and 5-HT3 receptors. slightly potentiates GABA-A (anxiolytic) and glycine receptors. releases endogenous opioid peptides (analgesic). may act to imitate NO in CNS.

ruffini endings

slow adapting deep mechanoreceptor in the subcutaneous tissue of humans. have large receptive fields to detect stretch eg at joints.

bradykinesia

slow initiation of voluntary movement eg in parkinsons

class I antiarrhythmic agents

slow the depolarisation phase using sodium channel blockers (inhibits action potential propagation). Ia are medium speed, Ib fast, Ic slow

class III antiarrhythmic agents

slow the repolarisation phase + increase refractory period

C fibres respond to which kind of pain?

slow, burning pain

difference between slowly adapting and rapidly adapting cutaneous mechanoreceptors

slowly adapting (SA) receptor endings signal prolonged skin contact, whereas RA receptors signal swift changes/vibrations only

which has higher input resistance, small or large motor units?

small

which depolarises first, small motoneurons or large motoneurons?

small (the recruitment principle)

demyelinated plaque

small areas of CNS suffering from demyelination, most commonly seen in MS

flocculus

small lobe of anterior cerebellum key in vestibulo-ocular reflex

dendritic spine

small membranous protrusion from a neuron's dendrite that typically receives (excitatory) input from a singlesynapse of an axon

which are more sensitive to small forces, golgi tendon organs on large motor units, or on a small motor unit?

small motor unit

chalazion

small painless sebaceous cyst of the eyelid resulting when a Meibomian gland is blocked

rostroventral lateral medulla

small region of brainstem, key in controlling BP; projects to the sympathetic preganglionic neurons in the spinal cord to excite sympathetic activity in heart + vessels

parvocellular ganglion cells

small retinal ganglion cells which respond to single cones/groups of same cones (hence colour sensitive). form 90% of retinal ganglion cell population

papilla

small rounded protuberance on a part or organ of the body

where/what are the dorsal column nuclei seen on the medulla?

small swellings either side of posterior midline, due to sensory relay nuclei transferring input from spinal cord to thalamus

drusen

small yellowish hyaline deposits that develop beneath the retinal pigment epithelium, sometimes appearing as nodules within the optic nerve head. most often in over 60s. associated with age-related macular degeneration.

difference between sensory and somatosensory

somatosensory refers specifically to touch, temp, proprioception and pain (eg not sight/hearing)

do presynaptic sympathetic neurons synapse in paravertebral ganglia at the same level as they emerge?

some do, other axons travel up/down the sympathetic chains to synapse at a different level

how does CSF travel down the spinal cord?

some flows into central canal, but most travels in the spinal subarachnoid space

cerebellar granule cell

some of smallest and most numerous neurons in brain. found in cerebellum, they travel from internal to external cortex, where they bifurcate into parallel fibres which form hundreds of synapses with purkinje cells

what is the most problematic effect of ECT?

some retrograde amnesia (hence it is only applied unilaterally to reduce this)

what do different subunits of voltage gated sodium channels do

some units which cross membrane, some units which detect membrane voltage, some units which form the pore, some units which can block/open the pore

what does contraction of the ciliary muscle do?

sort of 'pushes into' the eye, releiving tension of zonule fibres to allow the lens to become globular

allocentric space

space/movements centred in people or places other than oneself

difference between temporal and spacial summation

spacial = way of achieving an AP in a neuron with input from multiple presynaptic cells. temporal = by a single neuron using high frequency to amplify depolarisation + achieve an AP.

cajal

spanish neuroscientist who made detailed drawings of neurons in the brain, and began hypothesising that information is stored by modifying connection

tonotopy

spatial arrangement of where sounds of different frequency are processed in the brain. Tones close in frequency are represented in neighbouring regions

what is FLAIR

special MRI substance with long T1 to remove effects of fluid from images; useful for periventricular region close to CSF, eg infarction/MS/subarachnoid haemorrhage

photoreceptor cell

specialised type of neuron containing proteins which absorb photons, triggering change in cells membrane potential. include rods, cones + photosensitive retinal ganglion cells

axon hillock

specialized part of the cell body of a neuron that connects to the axon

what is the main function of the cortical region between the ascending and anterior rami of the lateral fissure?

speech production (broca's area)

foramen rotundum is a round hole in which bone?

sphenoid

which muscle changes size of pupil?

sphincter pupillae and dilator pupillae

which structure in medulla corresponds to the superficial dorsal horn of spinal cord?

spinal nucleus of trigeminal nerve

how do current motivation and state affect how pain is perceived?

spine-brain loops (forming the brain's 'conversation' with the spinal cord) use info like motivation and state (eg needing to move injured arm to eat/drink) to control descending modulation of pain signal

the cerebellum receives afferent connections from which 3 systems to co-ordinate movements?

spinocerebellar tracts (sensory info from joints/muscles), vestibular system, and motor cortex

what is the difference between the type of touch sensed by the spinothalamic and dorsal column pathways?

spinothalamic carries info of coarse touch and pressure. dorsal column carries info of discriminative (fine) touch

which afferent spinal tract enables nociception?

spinothalamic tract (delivers info from c fibres etc up to the thalamus)

what are the causes of trigeminal neuralgia?

squashing of trigeminal nerve root by superior cerebellar artery. shingles (post herpetic neuralgia)

what are the stages of anaesthesia?

stage I: analgesia, still conscious. II: excitement + delirium (think ethanol!), irregular respiration. III: surgical anaesthesia - unconscious, depressed resp+reflexes. IV: *overdose*. medullary depression - no spontaneous respiration, coma + death follow

what are the stages of sleep

stages 1-4 (from REM to stage 4), then 4-1, repeating in cycles around 6 times a night

stye

staphylococcus aureus infection of sebaceous/sweat glands on/below the eyelids causing a small painful red bump of water/pus.

give the 2 causative agents you would expect in a case of neurosurgical meningitis

staphylococcus aureus, gram negative bacteria including Psudomonas aeruginosa

amyloid

starchlike protein that is deposited in the liver, kidneys, spleen, or other tissues in certain diseases

describe the major loop of signal flow through hippocampus

starts in entorhinal cortex, projects to dentate gyrus. granule cells from there send mossy fibres to CA3. pyramidal cells from there run to CA1, and pyramidal cells of CA1 project to subiculum. signals then returned to EC

hypofrontality syndrome

state of decreased cerebral blood flow in the prefrontal cortex; symptomatic of schizophrenia, ADHD, bipolar disorder, and major depressive disorder

name the tiny projections which come off the top of the hair cells of the organ of corti

stereocilia

what medical therapies are likely to cause 2ndary hypertension

steroid therapy, combined oral contraceptive pill, monoamine ox-idase inhibitors.

what might you think about if a younger paitent had a central retinal vein occlusion?

sticky blood (thrombophilia screen, ask about contraceptive pill)

does glutamate inhibit or stimulate off-centre bipolar cells?

stimulate (hence they fire more in the dark)

does glutamate stimulate or inhibit retinal ganglion cells?

stimulate (hence they fire more in the light)

how does the periaqueductal grey create analgesia?

stimulation of PAG activates enkephalin-releasing neurons, which project to the raphe nuclei in brainstem. these release 5-HT down to the dorsal horn (laminae II) of spinal cord, signalling release of transmitters which bind μ-opioid receptors, inhibiting incoming nociceptive signals before they can be interpreted as 'pain'

what shape should a schild plot of a competitive antagonist be?

straight line with gradient of 1

describe the motor homunculus and somatosensory homunculus

stretching within the motor cortex and somatosensory cortex, they follow rouhgly the same pattern. 'leg' area is at the top near the midline, and the 'head' area is inferolateral

ocular dominance column

stripes of neurons in the visual cortex of certain mammals that respond preferentially to input from one eye or the other

what induces long term potentiation

strong tetanic activation of an afferent input sufficient to activate NMDA receptors (must overcomg the Mg2+ block). Ca2+ enters through NMDA, activates intracellular kinases, which increases postsynaptic AMPA receptors

good vision requires which 3 key things?

structurally healthy eye, proper focus of the eye, and intact neurological visual pathway

which part of the brain is responsible for learning and memory?

structures in the medial temporal lobes, part of the limbic system

what are the extrapyramidal pathways?

structures other than the corticospinal/bulbar tracts involved in motor control; the vestibulospinal, rubrospinal, tectospinal and reticulospinal tracts. (controlled by cerebellum, basal ganglia, vestibular nuclei, etc)

key differences between styes and chalazia

styes tend to be smaller/more painful, last for days rather than months,

which is arterial blood: extradural, subdural, subarachnoid haematoma

subarachnoid and extradural

blood in fluid collected from a lumbar puncture suggests what?

subarachnoid haemorrhage

what are the 3 meningeal 'compartments' outside of the brain

subarachnoid, subdural, epidural

how can you differentiate between subdural and epidural haematomas on CT scan

subdural are usually more longitudinally spread (less limited by vault bones), less dense, and make the sulci disappear

name 3 types of brain herniation

subfalcial, transtentorial, cerebellar tonsillar

in testing declarative memory, what is *free recall*?

subject asked to generate info from memory, eg participants are presented with a sequence of items, which they are subsequently required to recall in any order they wish

in testing declarative memory, what is *cued recall*?

subject is given a prompt/cue when asked to recall, eg participants given list of words, taken away, then 'Tell me all the words on the list that were animals'

instrumental learning

subjects learn that their responses have behaviourally significant outcomes: appropriate responses are *reinforced* by the behavioural outcomes

operant conditioning

subjects learn that their responses have behaviourally significant outcomes: appropriate responses are *reinforced* by the behavioural outcomes

classical conditioning

subjects learn the predictive value of a neutral event (ringing a bell) for another (food).

by which routes can glyceryl trinitrate be administed into the body

sublingually (tablet) or as a spray

substance P saporin technique to relieve pain

substance P saporin is a chemical mixture which can be administered to selectively destroy lamina I and II cells (part of spinothalamic tract). has little effect on acute pain but blocks chronic pain

which part of the basal ganglia is found outside the forebrain?

substania nigra; it is found in midbrain

SNpc stands for?

substantia nigra pars compacta

which brain structure releases the dopamine which acts on D1 and D2?

substantia nigra pars compacta

early symptoms of huntingtons

subtle problems with mood/cognition, followed by lack of coordination and unsteady gait

cataplexy

sudden and transient loss of muscle tone accompanied by full conscious awareness, often triggered by laughing, crying, terror, etc. affects roughly 70% of narcoleptics

what is orbital cellulitis? give some symptoms

sudden infection of the tissues around the eye (eyelids, eyebrow, and cheek). an *emergency! can spread to CNS*. painful, RAPD, reduced colour vision, proptosis. tender/warm erythematous skin associated with cold/fever + common in children

parieto-occipital sulcus

sulcus near the posterior end of each hemisphere that separates the parietal lobes and the occipital lobes. easily seen on medial hemisphere

flame shaped haemorrhages

superficial retinal haemorrhages which are flame shaped due to tracking of blood along horizontally arranged nerve fibres. occur in hypertension

which blood vessel can often squash the trigeminal nerve root? what does this cause?

superior cerebellar artery. causes trigeminal neuralgia.

which cranial fossa do the basal ganglia and thalamus lie in?

superior cranial fossa

where does info from both ears first come together to be processed

superior olivary nucleus

where is primary auditory cortex located?

superior temporal gyrus/lateral fissure

which 3 gyri lie anterior to the precentral sulcus?

superior, middle and inferior frontal gyri

topology

the way in which constituent parts are interrelated or arranged in space

maladaptive plasticity

theory behind phantom limb pain; in absence of a limb, other parts of the body take over that sensory area to 'fill the gap'

behaviourism

theory that all human/animal behavior can be explained in terms of conditioning, without appeal to thoughts or feelings, and that psychological disorders are best treated by altering behavior patterns/associative learning.

where is the interventricular foramen

there are 2 stretching upwards from the rostral end of third ventricle to the lateral ventricles

where are the nociceptors in the brain?

there are none (brain can't feel pain)

what is the basic mechanical model of pain?

there is a tissue injury, it hurts, and a defence response is sent to that area to help (much pain does not fit this model)

why do areas of ischemia appear bright on DWI

there is impeded water diffusion in extracellular space due to cytotoxic oedema. areas of restricted diffusion appear bright on DWI

why might parts of the brain appear paler in parkinsons disease?

there is loss of pigmented neurones (substantia nigra)

where is the second cranial ventricle?

there isn't one.

endogenous depression

there seems to be no reason/lifestyle change to cause the depression

are cell membrane chloride channels closed or open at resting potential?

theres a bit of flux, but mostly closed.

why is the cognitive effect of SSRIs seen within hours, but the mood response takes weeks?

theres an *idea* that SSRIs give you a positive bias in how you process the world - but this is just a framework; you need to go out in the world and experience things through this framework to change you enough to raise your mood

what is different about the afferents used in golgi tendon rather than muscle spindle?

they are Ib (not Ia) afferents. bit smaller and less sensitive.

what have amphetamines got to do with schizophrenia

they are associated with increased risk (probably to do with overloading dopamine release)

why are M1, M3 and M5 different from M2 and M4?

they are excitatory, and the even numbered ones inhibitory

what is the problem with CSF findings in MS?

they are nonspecific and can produce false positives/negatives

you cannot cause pschotic patients to take medication unless....?

they are sectioned

why are alpha 1 adrenoceptor blockers rarely used in hypertension?

they are too good - vasodilation is too strong and causes postural hypotension

why do muscarinic receptor antagonists increase heart rate?

they block the depressive input of the vagus nerve on the heart rate

why is it advantageous for most local anaesthetics to be weak bases?

they can exhibit ion trapping inside neurons (they work mainly on the inside of the cell membrane)

what is a key property of antihistamines which *cause sedation* vs those which don't?

they cross the BBB

why don't you give beta-blockers to type I diabetics

they dampen the adrenergic warning tremors/sense of foreboding induced by hypoglycemia, and also prevent adrenalin from stimulating the liver to make glucose, and therefore may make the hypoglycemia more severe

do pelvic splanchnic nerves join with spinal nerves?

they emerge with the spinal nerves from the ventral horn, but (unlike sypathetic fibres) they don't run in mixed bundles with spinal nerves - instead independent branches

give a situation where skeletal muscle blood vessels are innervated?

they never are

how would a tabetic gait affect a patients shoes?

they would be worn out uniformly across soles, because they are stomping down in a way that the entire flat foot strikes ground simultaneously, to give impact sensations

folia

thin leaflike folds in the cerebellar cortex

septum pellucidum

thin, triangular, vertical membrane separating the anterior horns of the left and right lateral ventricles of the brain. It runs as a sheet from the corpus callosum down to the fornix

septum pallucidum

thin, triangular, vertical membrane separating the anterior horns of the left and right lateral ventricles. runs as a sheet from the corpus callosum down to the fornix

what are the classic symptoms caused by damage to middle cerebral artery

think FAST. loss of motor function in arm/face

is the cortical mantle thicker or thinner in shizophrenia

thinner

name 3 intravenous anaesthetics

thiopentone, propofol, etomidate

most autosomal dominant familial alzheimers (small propotion of all alzheimers) is linked to which genes?

those encoding amyloid precursor protein (APP) and presenilins 1 and 2

which sympathetic preganglionic neurons project well away from the spinal cord?

those going to the adrenal medulla (they are the exception)

which kind of neurons are located in the region between the dorsal and ventral spinal cord?

those involved in processes you don't really think about; central pattern generator, relay neurons, etc.

which light rays that enter the eye are not refracted?

those which enter the centre of the eye + pass straight to the retina

how do patients with bilateral amygdala lesions differ from those with bilateral hippocampal lesions in fear conditioning and declarative knowledge?

those with amygdala lesions do not acquire conditioned autonomic responses to vis/auditory stimuli, but do acquire declarative facts. hippocampal lesions, is the other way around. (those with lesions to both acquired neither conditioning nor facts)

after oligodendrocyte damage in MS, how are more oligodendrocytes made for remyelination?

thought to be from a stem cell or oligodendrocyte progenitor cell pool. perhaps when this pool runs out, this marks the end of remyelination

gabapentin mechanism

thought to increase GABA biosynthesis and bind to voltage gated calcium channels, to help epilepsy + neuropathic pain

which cells enable us to see colours?

three different types of cone cell, which respond roughly to light of short, medium, and long wavelengths

name the headache in a subarachnoid haemorrhage

thunderclap

define 'metabolic half life'

time taken for plasma concentration of a drug to decline to half its original level

define consolidation in terms of memory

time-dependent process by which a new trace is gradually woven into the fabric of memory and by which its components and their interconnections are cemented together

what points should you pick up in a hearing loss clinical history?

time/age of onset, conditions in which hearing loss is apparent, concurrent illness/trauma/symptoms, family history, german measles in mothers early pregnancy? drugs (antibiotics?), noise exposure (machinery/music?).

suprachiasmatic nucleus

tiny paired nucleus in hypothalamus (above optic chiasm) which controls circadian rhythm. receives direct input from retina (daylight)

function of ossicles

to amplify vibrations (about 22x) between the outer ear and inner ear - important because vibrations in the inner ear travel through fluid which is more dense than air

what is the purpose of the inverse myotatic reflex?

to protect muscles from harming themselves by stopping their contraction when tension is too high

why do Ia afferents project to the brain?

to tell primary somatosensory cortex whats going on in muscle spindles (which/how fast muscles are stretching)

where do the zonule fibres attach?

to the ciliary body and the lens capsule

is the cranial dura tightly adhered to the brain or the skull?

to the skull. (in some parts it even fuses with periosteum)

hyperprolactinaemia

too much prolactin in blood. can cause spontaneous flow of breast milk + disruptions in the menstrual period in women, and hypogonadism, infertility, breasts and erectile dysfunction in men

treatment for acute anterior uveitis

topical steroid eyedrops, cycloplegics (fixes pupil in dilation to prevent painful pupil contraction)

ATRX

transcriptional regulator protein, mutations of which can affect DNA methylation/have been linked to cancer

TIA

transient ischemic attack; brief episode of neurological dysfunction resulting from an interruption in the blood supply (stroke) that the body is able to break down/resolve

praxis

translating an idea into action

why can't you give dopamine as a chemical directly to a patient?

transmitters wouldn't cross the blood-brain barrier (must give L-DOPA instead)

crystalline lens

transparent elastic structure behind the iris by which light is focused onto the retina of the eye

the vertebral arteries travel in which foramina?

transverse foramina of C2-C6

give some causes of neuropathy

trauma, diabetes, Post herpetic neuralgias, HIV, Alcohol, Chronic pain after surgery, Cancer

give 3 key signs of parkinsons disease

tremor at rest, mask like face (poor emotional control of face), difficulty initiating movements/slow movements

amitriptyline

tricyclic antidepressant

where does the latent phase of herpes VZV live?

trigeminal and dorsal root ganglia

general sensory info is carried in which nerves from the head?

trigeminal nerve (general sensory includes touch, pressure, pain and temp - not the special senses)

which nuclei receive all somatosensory information in cranial nerves?

trigeminal sensory nuclei

what can cause parkinsons disease loss of neurones to suddenly increase?

triggers such as life events, head trauma, viruses, dodgy recreational drugs (MPTP)

meningioma

tumor, usually benign, arising from meningeal tissue of the brain/spinal cord. causes compression on brain from outside to in

methods of administration of local anaesthetics

surface anaesthesia (topical solutions/spray/lozenge/powder) nerve block (inject close to a nerve trunk), spinal anaesthesia (inject into subarachnoid space)

in which 3 medical fields are general anaesthetics used

surgery, dentistry, intensive care

prefrontal lobotomy

surgical interruption of nerve tracts to and from the frontal lobe of the brain; often results in marked cognitive and personality changes. used historically to 'treat' mental disorders

resection

surgical removal of part of an organ

which is more frequently interfered with by strokes, swallowing reflex or speech?

swallowing

do axons shrink or swell when damaged

swell

how is the organisation of the enteric nervous system different to the other autonomic systems?

symp + parasymp systems are two-neuron (pre- and post-ganglionic), whereas the enteric division is organised in plexuses within the gut and can function without input from the spinal cord

how does the length of the pre- and postganglionic axons differ between symp- and parasympathetic nervous systems?

symp has short preganglionics + long post, whereas parasymp has long preganglionics, synapsing in local ganglia into short postganglionics

how does the location of the postganglionic neurons in the periphery differ between symp- and parasympathetic nervous systems?

symp has thoraco-lumbar outflow (sympathetic trunk, abdomen) parasymp has cranio-sacral outflow (cranial nerves III, VII, IX, X + pelvic splanchnic nerves)

is the ANS sensory, motor or both?

symp- and parasymp divisions are *motor* systems. enteric division is *mixed*

describe how micturition requires both autonomic NS and somatic motor NS?

sympathetic activity is inhibited/parasympathetic increased to cause detrusor contraction + bladder neck relaxation. somatic activity to urethral sphincter is inhibited (relaxes it)

sacral splanchnic nerves

sympathetic efferent nerves which arise from the sympathetic trunk, supplying the aortic and superior&inferior hypogastric plexuses (much of the abdomen, pelvis and anal canal)

kernig's sign

symptom of meningitis; patient cant extend leg at the knee when the thigh is flexed because of stiffness in the hamstrings

fentayl

synthetic μ-opioid receptor agonist analgesic with a rapid onset and short duration of action. >50 times more potent than morphine + heroin

which protein is important in causing parkinsons?

synuclein (duplications/mutations in SNCA gene)

what is the most common form of neurosyphilis?

tabes dorsalis

3 examples of dorsal column syndromes

tabes dorsalis (common form of neurosyphilis), friedreich's ataxia (genetic degenerative disease of dorsal columns+spinocerebellar tracts), brown-sequard syndrome (spinal cord hemisection) *all deficits in touch/proprioception*

why might worn shoes (equally across the sole area) be a sign of neurosyphilis?

tabes dorsalis (form of neurosyphilis) blocks transmission of proprioception up spine; to compensate patients stomp feet when walking + use impact to guide movement...called a *tabetic gait*

what causes tabetic gait?

tabes dorsalis (form of neurosyphilis) blocks transmission of proprioception up the dorsal spine; means patients don't know where their feet are when they walk, so will stomp

what is the difference in the onset and offset time of methadone compared to heroin?

taken by mouth (slower onset) and has a slower offset than heroin

thought broadcasting

talking out loud/belief that your thoughts can be heard or read by everyone

which more accurately correlates with alzheimers severity, tangles or plaques?

tangles

organ of corti is sandwiched between which membranes?

tectorial membrane above and basilar membrane below

limbic lobe

term used to refer to area of medial temporal lobe containing cingulate gyrus along with corpus callosum, hippocampal formation, and amygdala (important group for behaviour/memory)

cisternography

test to view brain/diagnose CSF leakage. contrast injected into subarachnoid space (lumbar), then patient tilted with the head down and a CT scan is performed to see where the CSF and the contrast is leaking out

maddox rod

testing device used to measure strabismus by separating the images of each eye so that neural feedback is unable to align eyes; they drift to their resting positions

ames test

tests ability of a drug/its metabolites to induce mutations in bacteria - use mutant bacteria which can't synthesise histidine - see if the drug enables it to grow anyway

visual field test

tests for blind spots. usually, patient puts head into a machine. lights flash, patient must say if they can see lights or not. black areas on the results show blind spots

which part of spinal cord is tested in Rombergs test?

tests sense of proprioception, which requires healthy *dorsal columns*

which drugs are classic examples of damaging teeth/tooth development as side effect

tetracyclines (type of antibiotics)

what forms the lateral walls of the third ventricle?

thalamus + hypothalamus

the posterior limb of internal capsule is between which structures?

thalamus and putamen/globus pallidus

name some brain areas active in pain processing

thalamus, S1&S2, insula, anterior cingulate cortex, prefrontal cortex, amygdala, hippocampus, posterior parietal cortex, basal ganglia, brainstem

psychosis

losing touch with reaity; hallucinations + delusions. caused by schizophrenia, bipolar disorder, major depressive disorder

aphasia

loss of ability to understand or express speech, caused by brain damage to language area

describe a absence seizure

loss of awareness,maintained muscle tone, time + memory loss of seizure

describe a tonic-clonic seizure

loss of consciousness, muscles contract, no breathing (tonic phase ~ 1min). then rhythmic muscle jerking (clonic phase ~ 1min). time + memory loss of seizure

lesion of the trigeminothalamic tract leads to loss of which function in the face?

loss of temp and pain sensation

agraphia

loss of the ability to write or to express thoughts in writing because of a brain lesion in language area

apraxia

loss of the knowledge to perform learned/purposful movements, due to brain damage of premotor cortex

akinesia

loss or impairment of voluntary movement

do inner hair cells produce an AC response at high or low freqencies?

low

does a drug with a high MAC have a low or high potency?

low (higher the MAC, lower the potency)

ideally, should a general anaesthetic have a high or low blood solubility? why?

low (more rapid onset and offset)

ideally, should a general anaesthetic have a high or low MAC?

low MAC (high potency)

which 3 things lead to renin release (from the JGA)

low arterial BP (baroreceptors), low Na+ in glomerular filtrate, and high sympathetic drive (Beta-1 receptors)

difference between low and high intensity CBT

low involves a questionnaire worked through alone (eg 'beating the blues'). high is CBT with a person.

which is transmitted to brain more anterior in the primary auditory cortex, high pitch or low pitch sounds?

low pitch (from the apex of cochlea)

name the 3 types of auditory nerve fibres

low threshold fibres (most sensitive, with high spontaneous firing rate), intermediate threshold fibres, and high threshold fibres (only fire for louder sounds, but have the most dynamic range)

is cauda equina syndrome an upper or lower motor neuron lesion?

lower

does tabes dorsalis affect Upper or LMNs?

lower motor neurons

which cells clear necrotic brain tissue?

macrophages

which cells mediate the destruction of oligodendrocytes and myelin in MS

macrophages

which is more lateral and which medial of the optic disc and macula?

macula is lateral, optic disc medial

name the specialised regions within the succulae and utricles, containing hair cells which can sense tilt information/horizontal acceleration

maculae

somatosensory cortex

main sensory receptive area in brain for sense of touch. located in postcentral gyrus in parietal lobe. aka primary sensory cortex

mossy fibres (cerebellum)

major input to cerebellum, coming mainly from cerebral cortex (pontocerebellar pathway) as well as vestibular nerve, spinal cord, reticular formation. passes through middle + inferior cerebellar peduncles, where each axon branches to innervate granule cells in several cerebellar folia.

name the 3 ossicles in order

malleus, incus, stapes

how does damage to the prefrontal cortex affect patients?

marked personality and behaviour changes with loss of forethought, planning

parkinsons symptoms

masked/apathetic face, resting tremor, akinesia, waxy complexion,

contraindications of doing a lumbar puncture in suspected meningitis

may have septicemia (increased risk of bleeding), or high ICP (brains can come out)

how might prior antibiotics affect meningitis?

may mask severity of illness

how do you calculate KB

measure effect of increasing dose of agonist on a tissue, then repeat whole thing, each time in presence of more antagonist. plot dose-response curves from results. for a level of response, calculate the mean dose ratio between antagonist + control. use schild equation to plot a graph of log(DR-1) vs antagonist concentration - a *schild plot*. the x axis intercept = log(KB)

what is 'accomodative power' of eyes

measure of your ability to change the focal length of the lens. AP (in dioptres) = 1/near point - 1/far point (both in metres)

central sensitisation leads to which kind of hyperalgesia?

mechanical hyperalgesia

is the supplementary motor area lateral or medial?

medial

what are the main inputs to the VPL

medial lemniscus and neospinothalamic tract

fasciculus gracilis

medial pathway of dorsal column of spinal cord; carries tactile sensation + vibration + proprioception *from the lower limb* to the *gracile* nucleus in the medulla

patient HM had which brain structures removed? what effect did this have?

medial temporal lobe; most of hippocampus, rhinal cortex, amygdala. dense *retrograde and anterograde declarative* amnesia for life

is damage to cerebral cortex or thalamus more likely to produce coma?

thalamus. even small lesions can induce coma in thalamus, whereas large bilateral lesions usually needed in cortex.

neurotrophic hypothesis of depression

that depression is associated with reduced BDNF(Brain-derived neurotrophic factor) levels in hippocampus; and antidepressants act by raising BDNF

MSN

medium spiny neuron. special type of GABAergic inhibitory cell representing 95% of neurons within the striatum (structure in the basal ganglia). can either be D1-type MSNs of the "direct pathway" and D2-types of the "indirect pathway".

which is deeper in the skin, merkel's discs or meissners corpuslces? which of these is associated with *ridges* on the fingertip - and which with grooves?

meissners are deeper and on the ridges. merkel's found in the grooves

basilar membrane

membrane in the cochlea that bears the organ of Corti. separates scala media from scala tympani

declarative memory

memories for facts and events that can accessed for conscious recollection (e.g. my first bike was a present on my sixth birthday)

procedural memory

memories that do not require conscious recollection including habits (e.g. being able to ride a bike).

deficits in learning/memory/retrieval are known as what?

memory impairments

which vaccines are given standardly in the UK for meningitis

meningitis C, and as of 2015, meningitis B is also being given to babies

aseptic meningitis

meningitis with non-bacterial causes (could still be an infectious agent!)

Neisseria meningitidis is aka

meningococcus

name 2 superficial touch receptors

merkel's discs and meissners corpuscles

what are SA1 receptors?

merkel's discs: superficial touch receptors linked mechanically to surrounding keratinocytes. keratinocytes *slowly* activate afferent fibres via a *synapse*, detecting fine touch eg braille

which DA pathway is related to negative symptoms of shizophrenia

mesocortical

which DA pathway is related to positive symptoms of schizophrenia

mesolimbic pathway

which stays open for longer, ionotropic or metabotropic channels?

metabotropic

are opiod receptors metabotropic or ionotropic?

metabotropic (opiod molecules are too large for ionotropic)

which general anaesthetic is associated with causing renal failure

methoxyflurane

which pathway in the optic radiation enables you to see superior visual field?

meyers loop

what are the precursors of macrophages in the CNS

microglia

which cells act as the first and main form of active immune defence in CNS?

microglia

where is the dopamine system localised in the brain

midbrain (esp. substantia nigra) involving the striatum + frontal lobe

pretectal nuclei

midbrain structure composed of seven nuclei; comprises part of the subcortical visual system. important in visual reflexes (accommodation, pupillary)

mesencephalon

midbrain; develops from middle neural tube.forms the tectum and cerebral peduncle

a classic 'FAST' stroke involves which cerebral artery

middle

which artery runs along the lateral fissure?

middle cerebral

which artery supplies nearly all the lateral hemispheres of the brain

middle cerebral artery

which key vessel runs through the insular cortex?

middle cerebral artery

which artery is likely to cause a stroke which affects upper limbs only?

middle cerebral artery (affects superior lateral surface of brain)

from which cranial fossa do the entrances to the pterygopalatine fossa arise? what are they called?

middle cranial fossa. there are two: foramen rotundum and pterygoid canal

what travels through the foramen spinosum

middle meningeal artery

what happens when microglia are activated?

migrate to lesions, proliferate, morphological changes in surface proteins/cytokines etc

chlorpromazine

mild alpha 1 antagonist, mild antihistamine, mild antimuscarinic agent previously used as *low potency typical antipschotic*

MAC

minimum alveolar concentration - the alveolar conc (% by volume) of anaesthetic which, when equilibrium has been attained, give *safe level of anaesthesia/lack of response to pain* in 50% individuals. analogous to *EC50*

auditory threshold

minimum amount of loudness required to hear a frequency

is 5HT an excitatory or inhibitory neurotransmitter?

mixed

is ACh an excitatory or inhibitory neurotransmitter?

mixed

is dopamine an excitatory or inhibitory neurotransmitter?

mixed

Raphe nuclei

moderate-size cluster of nuclei found in the brain stem; main function is to release 5HT to the rest of the brain. can 'turn off' nociceptive activity

how does dopamine affect D2 neurons

modulator that decreases the firing rate upon receit of incoming synaptic activity into D2 neurons (hence inhibits the indirect pathway)

how does dopamine affect D1 neurons

modulator that increases the firing rate upon receit of incoming synaptic activity into D1 neurons (hence excites the direct pathway)

molecular memory consolidation

molecular process by which long term conductivity of synapses is affected

what is the most effective treatment for mania

mood stabilisers eg *lithium* - literally just lithium.

how are dendritic spines linked to memory?

more appear after learning experiences

why is voltage change slower in a membrane with many many ion channels open?

more channels open = lower resistance. V=IR, so lower resistance means lower voltage

more APs in retinal ganglion cells indicates what?

more light

is depression worse in morning or evening?

morning

what does hyperreflexia indicate?

most common cause is a spinal cord injury (UMN lesion), but coud be due to hyperthyroidism, drugs, electrolyte imbalance, serotonin syndrome, MS, Reye's syndrome, brain trauma.

medulloblastoma

most common type of pediatric malignant primary brain tumor. located in dorsal medulla/cerebellum. can be treated relatively effectively

subiculum

most inferior component of the hippocampal formation. lies between (and receives input from) the entorhinal cortex and CA1. is the main output from hippocampus

what are the molecular targets of general anaesthetics

most likely to act on transmembrane part of postsynaptic neuronal ion channels, eg enhancing *GABA A* and *glycine* receptor affinity, and increasing current through leak K+ channels causing hyperpolarisation

how does neuronal composition of brain change from birth through childhood?

most neurons die well before birth. usually neurons don't increase in number, but do increase connections + size + spines

are CTs used in neuro for acute or chronic conditions?

most of the time use an MRI scanner, but CT sometimes used for acute

what are angiomas

mostly benign tumors formed of a mass of blood or lymphatic vessels. can compress tissues/nerves / be a sign of liver cirrhosis

are cell membrane sodium channels open or closed at resting potential

mostly closed

do the basal ganglia have an ipsilateral or contralateral effect?

mostly contralateral

which frequencies does age related hearing loss most affect?

mostly high frequencies (above 1000 Hz)

what is the output from the striatum?

mostly medium spiny GABAnergic (inhibitory) projections to globus pallidus

function of dorsal rami

mostly motor and sensory supply to the skin + muscles of the back

is the basal plate predominantly sensory or motor

motor

vestibulospinal and reticulospinal tracts are important for which key function?

motor control of muscle tone and posture of body

what do the basal ganglia do?

motor control/inhibtion. indirectly affect lower motor neurons of the brainstem and spinal cord of *contralateral side*, including connections via thalamus to motor cortex, and projections to reticular formation

lower motor neurones

motor neurones with axons which terminate on an effector - bringing the impulses from upper motor neurones out to the muscles

three key things the basal ganglia control

movement, posture, muscle tone

how will a histological Substania Nigra pars compacta section from a parkinsons patient appear?

much emptier; death of dopaminergic neurons in this region

how many neurons are myelinated by a single oligodendrocyte?

multiple neurons - each neuron is wrapped around by many different oligodendrocytes

vecuronium

muscle relaxant in the category of non-depolarizing blocking agents. Vecuronium bromide is indicated as an adjunct to general anesthesia, to facilitate endotracheal intubation and to provide skeletal muscle relaxation

dorsal spinocerebellar tract originates from where

muscle spindles and golgi tendon organs in muscles of trunk/lower limb

proprioceptors

muscle spindles, golgi tendon organs + other joint mechanoreceptors which signify stretch, tension + joint angles. sense bodyily position/mediate reflexes

why must a memory system be capable of *encoding*

must be able to process information (stimuli) presented to form a representation, which can then be stored/retrieved.

how does huntingtons damage the brain?

mutatedly long huntingtin protein accumulates in the brain. it is toxic and damages striatum (caudate nucleus + putamen) in particular

what is function of a1 adrenoceptors in the eye?

mydriasis

name the 2 main plexuses of the enteric NS

myenteric + submucosal

name + describe 4 most common refractive disorders

myopia (nearsightedness): difficulty in seeing distant objects clearly; hyperopia (farsightedness): difficulty in seeing close objects clearly; astigmatism: distorted vision resulting from an irregularly curved cornea presbyopia: leads to difficulty in reading/seeing at arm's length, linked to ageing

name 3 common disorders of eye focus

myopia (short sight) hyperopia (long sight) and astigmatism (distorted vision due to cornea)

what are the scientific words for short sighted and long sighted

myopia and hyperopia respectively

what % of neurons in a sample are stained by the golgi stain

mysteriously only around 10%

what is the antidote for heroin overdose

naloxone

name an antagonist of the 3 main opiod receptors. what is its use?

naloxone. used to reverse opiods effects, eg in overdose/to make pills safer

give the 5 major categories of abused drugs with an example of each

narcotic analgesics (heroine), CNS depressants (barbiturates/solvents/benzodiazepines), CNS stimulants (cocaine, amphetamine), hallucinogens (LSD), NMDA receptor antags (ketamine)

Neuroleptic malignant syndrome

nasty lifethreatening side affect of neuroleptics (usually involves drug interaction). involves muscle rigidity, fever, autonomic instability, delerium

L-DOPA

natural chemical precursor involved in synthesis of DA, NA, and adrenaline. can be manufactured as drug and given to help parkinsons disease + dopamine-responsive dystonia

which requires greater refractive power to focus on, near or far objects?

near

what is the near point of your vision

nearest point at which you are able to bring an object into clear focus

which lense corrects myopia

nearsightedness can be corrected with concave lenses

in active areas of brain, is a negative or positive charge induced below the scalp?

negative

is Neisseria meningitidis gram + or -

negative

medial lemniscus

nerve fibre tract that carries sensory information from the gracile and cuneate nuclei in the brainstem to the thalamus. decussates on the way

optic radiation

nerve pathway which connects LGN to V1

difference between dorsal nerve root and dorsal ramus

nerve root emerges from dorsal grey matter and *merges with ventral nerve root* to form spinal nerve. dorsal ramus is a branch of this spinal nerve, containing *mixed fibres*

reticular formation

network of pathways in brainstem connecting the spinal cord, cerebrum, and cerebellum; gives rise to reticulospinal tracts, receives sensory info, forms reticular activation system/respiratory centres, mediates level of *consciousness/attention*

huntingtons disease

neurodegenerative genetic disorder that leads to mental decline + chorea

homunculus

neurological "map" of the anatomical divisions of the body: two types; sensory and motor

glasgow coma scale

neurological scale that aims to give a reliable, objective way of recording the conscious/unconscious state of a person. measures eye opening, verbal, and motor responses

mirror neurons

neuron that fires both when an animal acts and when the animal observes the same action performed by another

climbing fibre

neuronal projections from the inferior olivary nucleus in medulla to the cerebellum (deep cerebellar nuclei and purkinje cells)

upper motor neurones

neurones from the cerebral cortex or brainstem which connect to and control lower motor neurones (these are the neurones found in motor tracts etc)

two main types of cells in the CNS are?

neurons and glial cells

name some cells of the PNS

neurons fibroblasts to make collagen, glia - schwann cells

how do dorsal + ventral horn differ histologically?per

neurons in ventral horn are much larger than ventral horn (but little red dots of glial cell nuclei will be the same size)

what do SCN neurons do?

neurons of suprachiasmatic nucleus are inhibitory, and project to other hypothalamus + midbrain regions influencing sleep/waking

aminergic nuclei

neurons that use monoamines as a neurotransmitter

name some other substances in postganglionic autonomic nerves that can act as neurotransmitters (aside from ACh and NA)

neuropeptides eg vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY); small molecules such as 5HT, ATP and nitric oxide (NO).

tolman

neuroscientist who challenged skinner/behaviourism by showing that animals had a 'cognitive map' in their heads and without conditioning were more often able to choose correct path in direction of food

orexin

neurotransmitter made in lateral hypothalamus which regulates arousal, wakefulness, and appetite. lack of orexin can cause narcolepsy

which basal ganglia pathway degenerates in parkinsons

nigo-striatal pathway

which is a neurotransmitter; nitrous oxide or nitric oxide?

nitric oxide (NO)

does any autonomic nervous system activity involve consciousness?

no

is the amygdala part of the basal ganglia

no

does N2O enhance GABA A receptor function?

no (though many general anaesthetics do)

Do Gabapentin and pregabalin bind to GABA receptors?

no - although they are very similar to GABA, they act instead via calcium channels

can the visual system detect the absolute value of light intensity?

no - can only detect *difference* in light intensity

are benzodiazepines dangerous in overdose?

no - extremely safe. may relax muscle too much leading to airway block, but is difficult to die from them

does the enteric nervous system connect at all to the spinal cord?

no - is a separate entity.

is the rate of slow adapting receptors constant throughout the duration of the stimulus?

no - it is slightly higher at the start, but then constant

do anaesthetics produce distortions in the lipid bilayer?

no - it was thought to be the case but is proven wrong

what is characteristic of an *autonomic* NMJ?

no fixed synapse/motor end plate - neurotransmitters are released from varicosities along the length of the unmyelinated autonomic axon.

what is the clinical significance of the anterior limb of internal capsule?

no real clinical significance

can you view the brain with normal X rays?

no, because of the skull (and because its hard to differentiate between soft tissues with x-rays). CT x-rays are much better

do substantia nigra neurons directly stimulate movement?

no, but they play an indirect role by regulating the more direct role of the striatum

can pain be confirmed or denied by reference to tissue damage/pathophysiology?

no, must rely on the patient as the authentic reporter - pain can be experienced even without tissue damage

are there inhibitory synapses at NMJs?

no, only in CNS

does angiotensin work on adrenoceptors?

no, works on its own AT receptors

do foetal alcohol syndrome patients always have facial defects?

no. Facial defects are a good indicator of brain damage but are not always found in those affected

name 4 things which can increase pain experience

nocebo (this pill will make pain worse), inflammation, stress-induced hyperalgesia (eg going to dentist), and neuropathic pain

withdrawal reflex

nociceptive inputs in lower limb/foot activate fast A-delta pathway, leading to flexor contraction and extensor inactivation (withdraw your limb by lifting up leg). also activates opposite leg extensors to push other leg down for support

what forms the free nerve endings of primary afferent Aδ and C fibres?

nociceptors

stereocilia

non-motile apical modifications of the cell, longer than microvilli and more similar to the cell membrane proper. found in vas deferens, epididymis, and inner ear

what causes microglia cell activation

non-specific reaction to almost all injury of the brain: Inflamm-ation, tumour, hypoxia, trauma, neurodegeneration, demyelination etc.

which parts of the cerebellum operate at a conscious level?

none; it operates at an entirely unconscious level

gliosis

nonspecific reactive change of glial cells in response to CNS damage. usually involves proliferation/hypertrophy of several types of glial cells, mainly astrocytes

which is better at activating alpha receptors, adrenaline or noradrenaline?

noradrenaline

sleep and wakefulness are controlled by which diffuse modulatory systems of the brain?

noradrenaline, acetylcholine, 5-HT, and dopamine systems

emmetropia

normal refractive condition of the eye. it focuses parallel light rays on retina without need for accomodation

how far down spinal cord does tectospinal tract travel?

not much further than cervical region

can T cells pass through the BBB?

not often, except in cases such as MS, where they are encouraged to by integrins / a breakdown of the BBB

why would you give ropinirole (dopamine agonist) for restless legs?

not really known - it is a paradox.

why don't all anaesthetics go through stage 1 of anaesthesia?

not that many of them have analgesic properties

phrenology

now abandoned study of the shape of skull as indicative of the strengths of different aspects of your personality.

pontine nuclei

nucei in the ventral pons which receive info from ipsilateral motor cortex, and project it to the contralateral cerebellum

in which part of the striatum does cocaine raise dopamine levels?

nucleus accumbens

name the limbic region of the striate nucleus

nucleus acucmbens

which is higher in the medulla, nucleus gracilis or nucleus cuneatus? which is more medial

nucleus cuneatus is higher, gracilis is more medial

locus coeruleus

nucleus in the pons involved with physiological responses to stress and panic; the principle site of brain NA synthesis

locus ceruleus

nucleus in the pons involved with stress, arousal/attention, posture. principal site for brain synthesis of NA. can receive signals from periaqueductal grey to help decrease nociception

tuberomammillary nucleus

nucleus of histamine-releasing neurones within dorsal hypothalamus, involved in arousal, learning, memory, sleep

hypaesthesia

numbness; diminished capacity for physical sensation, especially of the skin

subjective VS objective tinnitis

objective is produced by a physical source within the body - doctor can here during examination - more treatable. subjective there is no physical generator (can only be heard by the patient)

associative visual agnosia is associated in lesions where in the brain?

occipital and temporal cortices. mainly bilateral lesions

what does the posterior cerebral artery supply?

occipital lobe

what kind of stroke causes tunnel vision and why?

occipital lobe has dual blood supply from middle and posterior cerebral arteries - if one is blocked, you have 'macular sparing'

difference between on and off bipolar cells

off cells have AMPA receptor - their action is increased by glutamate, so they fire more in the dark. on cells have mGluR6, which finds glutamate inhibitory, so they fire more in the light

promazine

old but still used antipsychotic of the phenothiazine class

aside from the brain and spinal cord, which other structures are part of the CNS?

olfactory nerves, optic nerves, and the retina

in the CNS, what makes myelin?

oligodendrocytes

which cells produce white matter myelin

oligodendrocytes

cingulate sulcus

on medial hemispheres, sulcus which separates frontal and parietal lobes from the cingulate gyrus

cisterna magna is located where

on the back of the medulaa, below cerebellum and abve foramen magnum

where in the brain are cerebral aneurysms usually found?

on the circle of willis

where are 90% of type 1 synapses found?

on the heads of dendritic spines of striatal MSN

describe the relationship between intracranial pressure and volume

once the patient reaches a high ICP, a small increase in volume will cause a much larger jump in ICP

where is the caudate nucleus?

one in lateral wall of each lateral ventricle

delta waves

one of the lowest frequency and highest amplitude brain waves. associated with infants/adults in deep (slow-wave) sleep

acute anterior uveitis

one of the most common presentations of uveitis; front portion of uvea is inflammed

mammilary body

one of two small round structures on the undersurface of the hypothalamus. form the terminals of the anterior arches of the fornix. important for recollective memory

which has a larger soma, a motoneuron with many terminations, or one with very few terminations?

one with many terminations (requires more soma for nutrition for its branches etc)

understanding speech in a loud restaurant requires high or low threshold fibres?

only high threshold fibres. they require a louder volume to fibre, but have a more dynamic range than low threshold fibres for distinguishing sounds

is it possible for the eye to make slow movements (as opposed to saccades?)

only if there is a moving object for your eyes to track

is the atrophy in upper or lower motor neuron lesions?

only lower atrophy = wasting (of muscles in this case)

are benzodiazepines water soluble?

only one type - Flunitrazepam

which of these are 'readily reversible': coma, general anaesthesia, sleep

only sleep

how do opoid receptors cause inhibition?

open K+ channels (except Kappa opoid receptor, which closes Ca2+ channels) hence stopping action potentials

difference between closed and open medulla

open medulla is higher up and has *no central canal*

neuropore

opening in the anterior (rostral) or posterior (caudal) end of the neural tube of the developing embryo. failure to close causes NTDs

who do you have to notify if you see a patient in hospital with meningitis

the 'proper officer' at local council or local health protection team (HPT). They will pass on to public health england

what is the 'ISO' of an audiogram?

the *International Organization for Standardization* threshold levels that audiometers are calibrated to. these levels are used as a 'normal' so that when intensity of 0dB is indicated, the average person will be at the threshold for hearing that frequency. a -ve point indicates better than average hearing

second order afferent neurons carrying proprioceptive info and discriminative touch form what?

the *dorsal columns*

area V1

the *primary* visual cortex; part of the visual cortex which receives sensory input from the thalamus

second order afferent neurones carrying touch/pressure, pain and temp form?

the *spinothalamic tract*

nucelus of solitary tract

the *taste* nucleus which also receives unconscious info from carotid body + sinus (general visceral afferent). important for autonomic control and parts of it form the dorsal inspiratory respiratory centre

kainate receptor

the 3rd main type of glutamate receptor (aside from AMPA and NMDA). they are ion channels of 4 subunits, permeable to Na+ and K+

in testing declarative memory, what is *recognition*?

the ability to correctly decide whether they have encountered a stimulus previously in a particular context; participants shown list of words, then presented with individual words: 'old or new word?'

what determines the shift of a dose response curve between two experiments, with and without a competitive antagonist?

the antagonist affinity for the response-inducing receptor, and the efficacy of the antagonist once bound.

telencephalon

the anterior of the two vesicles formed by specialization of the prosencephalon in embryonic development. Forms the cerebrum. Called also endbrain

panums zone of fusion

the area in and about the macula of retina in which stimulation of noncorresponding retinal points results in stereoscopic vision

centre-surround receptive field

the area within a ganglion cells receptive field is divided into centre (can contain either ON or OFF bipolar cells) and surround (will contain opposite type bipolar cells to centre). this functions to *emphasise edges/contrast in visual field*

blink artefacts in EEGs are caused by?

the blink musculature

drainage of aqueous humour from the eye is through where?

the canal of schlemm

which part of the lateral ventricles have a choroid plexus

the central part, and the superior part of the inferior horn (not anterior or posterior horn)

name the middle (vascular) layer of the eyeball

the choroid (forms ciliary body and iris anteriorly)

neuropil

the complex network of unmyelinated axons, dendrites, and glial branches that form the bulk of the CNS grey matter

blood:air partition coefficient

the conc of a substance in blood, relative to that in the air *at equilibrium*

pterygopalatine fossa

the deepest part of the pterygopalatine fissure (between sphenoid/maxilla/palatine bones)

where are the spines found on a medium spiny neuron?

the dendrites

metastasis

the development of secondary malignant growths at a distance from a primary site of cancer

tectum

the dorsal part of the mesencephalon, responsible for auditory and visual reflexes

how do middle ear bones amplify ( increase the pressure of) soundwaves?

the ear drum has 20x the surface area of the stapes, hence the stapes *concentrates* the pressure. this is added to by the lever action of ossicles and buckling of ear drum

the pineal gland is a component of which part of the diencephalon?

the epithalamus

superior colliculus is important for controlling movements of which organ?

the eyeballs

what happens if you stimulate the *frontal eye field*?

the eyes will look in the opposite direction to the side of the brain you stimulated

which parts of upper body do not have sensory input to the fasciculus cuneate? what structure carries corresponding info from these places?

the face and ear - info from here is carried by *principal sensory nucleus of trigeminal nerve*

which cranial nerves don't attach to the brainstem

the first two (olfactory and optic) which attach directly to the forebrain

soundwaves travel along which duct of the cochlea?

the floor of the scala media; the basilar membrane

what is ultrafiltrate?

the fluid present in the nephron; the glomerular filtrate

corpora quadrigemina

the four colliculi—two inferior, two superior—located on the tectum (the dorsal midbrain). they are reflex centres for vision + hearing

habitutation

the gradual waning of a response with repeated presentations of a stimulus (cancels out background information)

flexor reflex afferents

the group of nociceptive afferent neurones that transmit information via Aδ and C afferent fibers and produce the flexor withdrawal reflex

dominant hemisphere

the hemisphere which has the language areas in it (usually the left)

alexia

the inability to see words or to read, caused by damage to the language area of brain

which basal ganglia pathway involves external globus pallidus and subthalamic nucleus?

the indirect pathway

which two key arteries supply the brain?

the internal carotid arteries and internal carotid arteries

which pupillary light reflexes are affected in transtentorial herniation?

the ipsilateral oculomotor nerve is compressed, so ipsilateral pupil is areactive. contralateral consensual light reaction is preserved because optic nerve still intact

Pure tone audiometry

the key hearing test used to identify hearing threshold levels of an individual, enabling determination of the degree, type and configuration of a hearing loss

genu

the knee OR a part of certain structures resembling a knee (eg the bend in the internal capsule)

temporal horn of lateral ventricle

the largest, inferior horn of lateral ventricle, curving around the thalamus

cortical mantle

the layer of unmyelinated neurons (the grey matter) forming the cortex of the cerebrum.

which side of vision is usually neglected by hemispatial neglect? why?

the left side, because the lesions most often occur in the right parietal lobe

at which level do spinothalamic tract neurons cross the midline

the level at which the C&Aδfibres enter the spinal cord + synapse with 2nd order neuron

which part of the homunculus is supplied by the anterior cerebral arteries

the lower limb (medial part)

where do most corticospinal axons cross the midline (decussation of the pyramids)?

the lowest part of the medulla

the two sides of the diencephalon are separated by what?

the lumen of the third ventricle

bupivacaine

the most commonly used local anaethetic in epidurals

pethidine

the most widely used opioid analgesic in labour and delivery

which brain area seems to be most involved in memory priming

the neocortex

why was it comparitively easy to see which neurons are being lost in parkinsons disease?

the neurons are part of the substantia nigra; contain black pigment (much more noticable than just a random bit of grey matter)

which part of the ear contains inner hair cells and outer hair cells?

the organ of corti (in the scala media)

what does the amplitude of a sound wave correlate to?

the perceived loudness

in vision, what is the receptive field

the photoreceptors/part of the retina which connects to a ganglion cell is the *receptive field* of that ganglion cell

uvea

the pigmented layer of the eye, lying beneath the sclera and cornea, and comprising the iris, choroid, and ciliary body

what does the frequency of a sound wave correlate to?

the pitch

fulcrum

the pivot about which a lever turns

what is the neuranatomical region of M1? include its brodmann area

the primary motor cortex (M1) is found in the precentral gyrus in the frontal lobe. brodmann area 4

descending corticospinal fibres form a prominant ridge on the ventral medulla called?

the pyramids

coronary angiography

the radiographic visualization of the coronary vessels after injection of radiopaque contrast media

the rods/cones connected to a bipolar cell form what?

the receptive field centre (if directly connected) or the receptive field surround (if indirectly connected via horizontal cell)

where to the rubrospinal tract fibres originate?

the red nucleus (in rostral midbrain)

why mustn't you forcefully rupture a stye

the staphylococcus aureus with spread

what is the only monosynaptic reflex in the body?

the stretch reflex, initiated when a muscle is stretched (generated in muscle spindles)

the spinal cord is shorter than vertebral column, so to emerge from their correct *intervertebral foramen*, lower spinal nerve roots descend to it *in which meningeal layer?*

the subarachnoid space

sensitization

the sudden enhancement of responses to a stimulus after exposure to a highly arousing event

how is the cerebellum attched to the brainstem?

the superior, middle and inferior peduncles (masses of nerve fibres either side of the 4th ventricle)

all pathways carrying specific info to the cerebral cortex synapse where?

the thalamus

where do primary afferents entering the brainstem via the trigeminal nerve terminate?

the trigeminal sensory nucleus, one of the cranial nerve nuclei in the pons

optic nerves pass through the optic chiam to become what?

the two optic tracts (L + R)

what proportion of the vertebral column is occupied by the spinal cord?

the upper 2/3rds. (it terminates at L1)

which reflexes are eye movements to *track a moving subject*

opto-kinetic reflexes

what does OPV stand for?

oral polio virus

which characteristic facial expressions do mice show in response to pain which humans also show

orbital tightening, nose bulge, cheek bulge

tonotopic map

orderly projection of inputs originating from the cochlea to sensory areas in the brain, such that neighboring neurons in the target regions respond to progressively higher frequencies

hypocretin is AKA

orexin

name the neurons in the lateral hypothalamus which activate the ascending arousal system

orexin neurons

organ of corti

organ lying against the basilar membrane in the cochlear duct, containing neuroepithelial hair cells/several types supporting cells. converts sound virbrations into cochlear nerve signals

is CTZ inside or outside the bloodbrain barrier?

outside

hyperacusis

oversensitive hearing due to increased irritability of the sensory neural mechanism; intolerance to ordinary sound levels. exacerbated post-earplugs

what are RA2 receptors?

pacinian corpuscles: fluid-filled-capsulated ending of a sensory nerve, found deep in dermis. acts as a rapidly adapting receptor for pressure and vibration

scoville and milner

pair who studied HM and first wrote a famous paper (based on him) which outlined the hippocampus as being needed for transforming short term memories into long term memories

what are the two major neuronal inputs to purkinje cells of cerebellum? are they excitatory or inhibitory?

parallel fibres and climbing fibres (both glutaminergic excitatory)

when baroceptor firing increases, how is parasympathetic and sympathetic activity changed?

parasymp becomes more active and symp becomes less active (to lower BP)

sympathetic + parasympathetic systems: which is more 'direct' and which is more 'divergent'?

parasymp outflow = more direct (local ganglia). symp outflow = more divergent eg each preganglionic neuron can produce responses coordinating between different internal organs/targets

is micturation sympathetic or parasympathetic

parasympathetic

is pupil constriction symp- or parasympathetic?

parasympathetic

hemispatial neglect

parietal cortex lesion means attention/awareness of one half of space is compromised. when asked to copy pictures, though patient can see the whole image, they only draw one half, ignoring the other.

what is the major cause of hemispatial neglect?

parietal cortex lesions (usually right parietal)

stimulation of the subthalamic nucleus helps treat which disease? why?

parkinsons (they carry a portable electric stimulator).

tremor at rest, slow movements, rigidity, postural instability. classic symptoms of what?

parkinsons disease

what are the two primary output nuclei of the basal ganglia system to the motor thalamus?

pars reticulata and globus pallidus internal segment

helicotrema

part of cochlear apex where the scala tympani and the scala vestibuli meet; hair cells near here detect low frequency sounds

brodmann area 7

part of superior parietal lobe (posterior to primary somatosensory cortex). uses visual and proprioceptive info to located *where* objects are in space

where is the fusiform gyrus

part of temporal lobe between the inferior temporal gyrus and the parahippocampal gyrus

striate cortex

part of the occipital cortex that receives the fibers of the optic radiation from the lateral geniculate body and is the primary receptive area for vision. includes V1

posterior spinocerebellar tract

part of the somatosensory system ; runs parallel to anterior spinocerebellar tract, up the latero-dorsal outer edge of spinal cord. conveys unconscious proprioceptive info from the body to the cerebellum

tinnitus

pathologically generated sounds; ringing/hissing/roaring or buzzing in the ears or head

dissociative anaesthetic

patient is aware of surroundings, but is detatched from them, eg ketamine

if you electrically stimulate the somatosensory cortex what happens?

patients feel a tingling sensation on the contralateral side of the body

pain wind up

perceived increase in pain intensitywhen a given stimulus is delivered repeatedly above a critical rate. caused by repeated stimulation of C fibers, leading to progressively increasing electrical response in dorsal horn neurons

schultz

performed experiments on dopamine neurons in striatum, finding that this area seems to be most involved/changed in operant conditioning

which brain structure, seen in a midbrain cross section, has descending control over pain?

periaquaductal grey

describe plasticity in pain system at a peripheral level

peripheral sensitization, denervation, ectopic activity (random pain)

how do you describe the meningitis rash?

petechial/purpuric non-blanching rash or signs of meningitis

how are mirror boxes used to treat pain?

phantom limb pain patients can feel like their fist is clenched/nails digging in. mirror box used to make it seem like patient is looking at their fist and unclenching it - alleviates pain in short term

aside from alzheimers, name some other tauopathies

pick's disease, corticobasal degeneration, progressive supranuclear palsy, frontotemporal dementia with parkinsonism

which do people remember better, pictures or words?

pictures

which small structure behind the third ventricle can calcify (without causing problems) from an early age?

pineal gland

this scan shows calcification in which 3 key areas?

pineal gland, and both choroid plexuses

vasogenic brain oedema

plasma-filtrate (incl. proteins) oedema in the interstitium of the brain caused by breakdown of the tight endothelial junctions that make up the blood-brain barrier

peripheral sensitisation to pain

plastic changes in C fibre axon terminals lead to amplified pain post injury (particularly more sensitive to thermal stimulation - think sunburn)

central sensitisation to pain

plastic changes in dorsal horn neurons (involving microglia) amplify incoming pain sensory info *from A and C fibres* - this is troublesome in pain relief

basilar artery runs up the front of which part of brainstem

pons

3 structures of the hindbrain

pons, medulla, cerebellum

optic ataxia

poor hand/eye coordination - inability to benefit from visual guidance in reaching for an object.

tuberoinfundibular system

population of dopamine neurons in the arcuate nucleus of hypothalamus. project to pituitary median eminence to prevent prolactin secretion

pars compacta

portion of the substantia nigra containing dopaminergic neurones (they die in parkinsons)

is streptococcus penumoniae gram + or -

positive

what kind of symptoms are relieved by 'typical' antipsychotics

positive symptoms eg hallucinations/delusions

what are the two overarching reasons that drugs induce dependence

positively reinforcing (drug is rewarding/pleasurable) and negatively reinforcing (drugs taken to avoid withdrawal syndrome)

what is the neuranatomical region of primary somatosensory cortex? include its brodmann area

post central gyrus, parietal lobe. brodmann area 3, 1 and 2 (from ant to posterior)

name 4 gyri of parietal lobe

postcentral, supramarginal, angular, intraparietal

are the inferior cerebellar peduncles on the anterior or posterior surface of the medulla?

posterior

which cerebral artery supplies the thalamus

posterior

which is more problematic; lesions in the anterior or posterior limb of the internal capsule?

posterior

after transtentorial herniation, infarctions occur in the terriftory of which artery?

posterior cerebral artery

which artery supplies most of the visual areas of the brain?

posterior cerebral artery

which artery supplies the dorsolateral medulla

posterior inferior cerebellar artery (PICA)

PICA

posterior inferior cerebellar artery, largest branch of the vertebral artery, and one of the three main arterial blood supplies for the cerebellum

rachischisis

posterior neuropore of the neural tube fails to close in development; vertebrae overlying do not fully form + remain unfused and open, leaving the spinal cord exposed

which kind of synechiae are associated with AAU

posterior synechiae

what is NMDAR

postsynaptic ligand-gated ion channel which transports cations (Na+/Ca2+) into dendrite. opens only when glutamate and glycine (the ligands) are bound to the receptor, and the postsynaptic cell is depolarized (which de-attracts the Mg2+ blocking the channel)

what is AMPAR?

postsynaptic ligand-gated ion channel. when glutamate (the ligand) binds, it transports cations into dendrite

what is inversly proportional to Minimum Alveolar Concentration?

potency

tetrodotoxin

powerful neurotoxin found in some sea creatures. highly selective voltage gated Na+ channel antagonist - prevents action potentials, causing paralysis whilst conscious

what are the vascular causes of 2ndary hypertension?

preeclampsia, coarction of aorta, renal artery stenosis

laser peripheral iridotomy

preferred procedure for treating angle-closure glaucoma caused by pupillary block. laser beam creates small hole allowing the aqueous humour to pass directly from the posterior chamber into the anterior chamber, bypassing the pupil and equalising pressure

problem solving and goal-directed behaviour is dealt with in which part of brain?

prefrontal areas of frontal lobes (executive function)

name the cortex rostral to the motor areas of the brain

prefrontal cortex

which region of the brain expierences particular cell death in chronic pain patients

prefrontal cortex

are autonomic neurons myelinated?

preganglionic axons are lighty myelinated, and postganglionics are unmyelinated

which neurons of the ANS are located in the central nervous system?

preganglionic neurons

which neurons are found in the lateral horn of the spinal cord?

preganglionic sympathetic neurons

SMA and PM are both included in which region of the brain?

premotor cortex

which has higher level coding in, M1 or Premotor cortex?

premotor cortex. (premotor area has activity when you are just thinking about a movement, supple

name the condition whereby elasticity of the lens decreases so lens fails to change to globular shape during accomodation?

presbyopia

how do OHCs perform *electric-mechanical transduction*?

prestin they contain causes them to contract when stimulated, feeding energy back into the basilar membrane + boosting vibrations of sound. creates *cochlear amplification*. without OHCs, our hearing *sensitivity* decreases greatly

when do huntingtons patients stop making chorea movements?

pretty much never except during deep sleep

where do the basal ganglia outputs project to?

primarily the thalamus (only those parts connected with frontal cortical regions, and those regions important in motor control - VA, VL, DM). also superior colliculus (eye mvments), reticular formation, pedunculopontine nucleus, habenula

which is more sensitive to produce movement due to electrical stimulation; primary or premotor cortex?

primary (premotor will still produce movement, but requires higher stimulation)

what is brodman area 4?

primary motor cortex

what is the function of brodmann areas 17

primary visual cortex - the simplest, earliest cortical visual area, interpreting 'edge detection' information from the LGN of thalamus and sending it on to V2

what is the neuranatomical region of V1? include its brodmann area

primary visual cortex is located at the calcarine sulcus. brodmann area 17

snellen chart

printed card with letters in lines of decreasing size; used to test visual acuity.

which neurodegenerative diseases are human-human transmissable

prion protein diseases (Creutzfeldt-Jakob-Disease, Gerstmann-Sträussler-Scheink er-syndrome, etc). amyloid beta can also be transmitted (linked to alzheimers)

why do amnesia patients lose their more recent memories and retain older ones?

probably because most amnesia patients have damage to the hippocampus, and the older memories have, over time, become more located/connected to the *cortex* than the hippocampus(+ associated structures): called *consolidation*

describe axon guidance

process by which neurons send out axons to reach the correct targets. at the tip of growing axons is a motile *growth cone* which contains receptors for attractive/repellant 'guidance cues' in the environment. these attractive molecules are turned off upon reaching target

tectospinal tract function

produces reflex (involving superior calliculus) in which head turns to face an auditory/visual stimulus

symptoms of MND initially present as?

progressive weakness, muscle wasting, muscle fasciculations, spasticity/stiffness in arms + legs, struggle swallowing/breathing, hyperreflexia

ascending arousal system

projections from the brainstem/posterior hypothalamus throughout the forebrain,

in which cerebral lobes is visuospatial function organised?

projections to parietal lobes

in which cerebral lobes are faces and objects recognised?

projections to temporal lobes (memory)

general seizures

prolonged synchronous discharge of many neurons involving whole brain - fast onset.

which betablocker is commonly used in thyroid storm and why?

propanolol. beta blockers reduce the effect of circulating thyroid hormone on end organs. propanolol blocks both B1 and B2 receptors especially well

which is least selective for B2 adrenoceptors, propranolol, atenolol or metoprolol?

propranolol

put these in order from fastest to slowest: thermoreceptors, proprioceptors, nocicptors, cutaneous mechanoreceptors

proprioceptors, cutaneous mechanoreceptors, thermoreceptors, nociceptors

what is the function of hyperalgesia after injury

protect the injury to allow recovery and repair

functions of the outer ear

protection, amplification, localisation (where has the sound come from in vertical/horizontal planes)

what is the main function of pain

protective - it prevents damage from occuring.

α-Synuclein

protein abundant in neural tissue, which when mutated, aggregates to form insoluble fibrils known as Lewy bodies

postsynaptic density

protein dense specialization attached to the postsynaptic membrane - concentrates neurotransmitter receptors etc to align with *active zone* on presynaptic neurone

PKC is short for?

protein kinase C

presenilin

protein sub-component of gamma secretase that is responsible for the cutting of Amyloid precursor protein. mutations in presenilin gene hence cause early onset familial Alzheimer's Disease

ephrin

proteins which act on the ephrin receptor. repellent on axon growth cones so responsible for segmental pattern of spinal nerves

name 2 types of hypertension aside from systemic

pulmonary + portal hypertension

in which cells in the body does phosphorlyation of AMPA receptors *decrease* AMPA receptor expression?

purkinje cells in cerebellum. (all other cells, it would *increase*)

how does pushing in the oval window (by the stapes) affect the round window?

pushes round window out into middle ear cavity (fluid in the inner ear is not compressed)

two ways of treating cerebral berry aneurisms

put clips around their necks or 'fill them up'/interventional radiology

where are the pyramids and olives found on the medulla?

pyramids are lateral to the ventral midline fissure, and olives are lateral to the pyramids

how is *quality* of a sensory stimuli encoded in the nervous system?

quality of a stimulus (is it pressure, heat, etc) is encoded by the identity of the afferent fibre its stimulates, i.e. the receptor type + its location in body

which are more addictive, drugs which are eliminated quickly, or slowly?

quickly, since slow clearance of a drug diminishes severity of acute withdrawal. (but longer lasting drugs can increase addiction by increasing duration of action on target proteins)

side effects of TCAs

quite sedative, a1 adrenoceptor antagonists (lower BP), muscarinic receptor antagonists

once they start asymmetric divisions to develop neurons, what are neuroepithelial stem cells renamed?

radial glial cells

myelography

radiographic examination of spine. contrast medium injected into spine to detect pathology of the spinal cord, including the location of a spinal cord injury, cysts, and tumors

deprenyl side effects

raises BP and is metabolised into *metamphetamine* (crystal meth.... a neurotoxic substance)

nystagmus

rapid involuntary rhythmic movement of eyeball. may be horizontal, vertical, rotatory, mixed

guillain-barre syndrome

rare polyneuropathy. fast onset muscle weakness as a result of autoimmune attack on the myelin of *peripheral nerves*. (this immune dysfunction may be triggered by an infection)

tyosine hydroxylase function

rate-limiting enzyme of catecholamine biosynthesis; converts tyrosine to L-DOPA

omni-directional

receiving signals from or transmitting in all directions (eg our sense of hearing)

which type of past memories are affected first in alzheimers and why?

recent *episodic* memories (due to hippocampus being first affected)

mesencephalic

relating to the midbrain (mesencephalon)

dystonia

relatively fixed abnormal postures in face/neck/trunk/limbs. a result of basal ganglia disorder

are the neural signals in the ON- and OFF-centre retinal ganglion cells separate or merged?

remain segregated in the retina and the LGN, then merge completely in the complex cells in primary visual cortex (V1)

what are the adverse sympathetic affects of adrenaline?

remember 'CATTRAP' : cold sweat, anxiety, tremor, tachycardia, reduced capillary refill, arrythmia, pallor

how do you treat cataracts?

remove clouded lens and put in a plastic one

why might you perfrom a ventrolateral chordotomy? how effective is this?

removes the part of the spinal cord where the spinothalamic tract is located - removes pain for *several segments below the cut* - though due to spinal plasticity this will return after a few weeks

what are the renal causes of secondary hypertension?

renovascular disease, glomerulonephritis, chronic pyelonephritis

long term potentiation

repeated presynaptic stimulation of a nerve that results in the long-lasting increased strength of a synapse. necessary for learning and memory formation ('if you use it, it gets stronger')

why was clozapine drug withdrawn as unsafe?

reports of agranulocytosis leading to death in some clozapine-treated patients (though it is now reinstated, provided sufficient blood monitoring)

impedance

resistance to flow/movement. eg 'how much does the material *impede* movement'

function of alpha retinal neurons

respond rapidly to movement in peripheral field (larger neurons)

function of beta retinal neurons

respond to fine detail in vision (smaller neurons)

is there a resting or intention tremor in parkinsons disease?

resting

chorea

restless, rapid, involuntary, dancelike movements (often resembles fragments of purposeful movements) seen in huntingtons disease

which is more important for consciousness, reticular formation or cerebral cortex?

reticular formation (even a small lesion in it can produce coma, unlike the cortex)

the axons of which cells weave together to create the optic nerve?

retinal ganglion cells

what kind of memory loss is seen in alzheimers

retrograde memory impairment (recent memory goes first, then loss extends back into the past as disease progresses)

moclobemide is a 'RIMA.' what does this mean?

reversible inhibitor of monoamine-oxidase-A

which pigment gives the retina its purple/red colour?

rhodopsin

which sinister (if clever) application does Flunitrazepam have

rhohipnol - date rape drug - used because it is powerful hypnotic + water soluble, but metabolised in such a way as not detectable the next day

optokinetic reflex

rhythmic nystagmus movements involving the visual system and its neural pathways. eg when looking out of train window, eyes follow a moving object with until it moves out of the field of vision, at which point eyes moves back to the position it was in when it first saw the object

gyri

ridge/elevation between two sulci on the cerebral surface in the brain

which amygdala is most involved in fear/negative processing

right amygdala

zonule fibres

ring of fibrous strands connecting the ciliary body with the crystalline lens of the eye. collectively known as suspensory ligament of eye

ciliary muscle

ring of smooth muscle in eyes middle layer which controls *accomodation* and *aqueous humour flow*.

vestibulo-ocular reflex

rotation of head in one direction eg to the right, activates vestibular apparatus and medial/lateral rectus muscles to move eyes to rotate in opposite direction (the left). maintains a fixed gaze on an object even when head moves

which is bigger, pterygoid canal or foramen rotundum

rotundum

which spinal pathway comes from the red nucleus and intermingles with the descending corticospinal tract?

rubrospinal tract

myelomeningocele

sac containing part of the spinal cord +meninges protrude through a gap in the vertebral column

most common type of cerebral aneurysm

saccular aneurysms; aka berry aneuryms (appear as round outpouchings)

name the leaping type of propagation down a myelinated axon

saltatory conduction

which cells surround dorsal root ganglia?

satellite glial cells

give 2 structural features which decrease potency of anaesthetics

saturation and hydrophilic groups (eg -OH, -NH2)

cochlear duct aka?

scala media

3 layers of the cochlea are?

scala tympani, scala media, scala vestibuli

drugs which block NMDAR (eg ketamine) have side effects indistinguishable from which psychotic disease?

schizophrenia

what are type II sensory fibres?

secondary afferent neurons which provide position sense of a still muscle, fire when muscle is static

netrins

secreted molecules that can act to attract or repel growth cones of new axons by binding to their receptors

lashley

sedated animals and knife-cut specific areas of their brain to see how they changed - tried + failed to find the engram . concluded memory is distributed

where are the red nuclei found in a midbrain cross section?

see pic

selegiline

selective irreversible MAO-B inhibitor - blocks break down of dopamine, NA, Ad, 5HT in the brain. used in early-stage parkinsons (not depression). has cardiac side effects

rolipram

selective phosphodiesterase-4 inhibitor (procognitive effects), once used to treat depression but now in research/development

SSRI stands for

selective serotonin reuptake inhibitor

what kind of memory is this: 'the capital city of france is paris'

semantic (factual) memory

interoception

sensitivity to stimuli originating inside of the body

is the alar plate predominantly sensory or motor?

sensory

acoustic neuroma

tumour which grows on the 8th nerve (affects hearing early on) and will soon impinge on the facial nerve too; illustrates the importance to the close relationship of the VIIth and VIIIth nerves

what might compress cranial nerves emerging from the brainstem?

tumours or aneurysms

weber's test

tuning fork is rung held to the top of head. distinguishes unilateral conductive hearing loss (tone heard in affected ear) from unilateral sensorineural hearing loss (heard in non-affected ear)

how might acute infarction change the appearance of neurons

turns the area pale

describe the retinal blood supply

two circulations both supplied by ophthalmic artery; uveal circulation (outer + middle layers of retina) and retinal circ (inner layer, travels with optic nerve as central retinal artery)

grid cell

type of neuron which interacts with hippocampal place cells to help keep track of spatial location even in absence of visual/auditory/tactile cues.

MR perfusion imaging

type of perfusion scanning using MRI and contrast. can show areas most perfused --> indicates those most active.

tyramine reaction

tyramine is normally broken down by MAO before it gets into blood, but if on non-selective MAO-inhibitors, it can enter blood, damaging VMAT 2 so monoamine storage vesicles release their cargo into cytoplasm and - pushes transporters to transport monoamines the 'reverse' way - into synapse. causes hypertensive crisis

where is aqueous humour produced? is this sympathetic or parasympathetically controlled?

ultrafiltration in the ciliary body. symp (B1 and B2 adrenoceptors).

in pavlovs experiment, what was the conditioned/unconditioned stimulus and response?

unconditioned stimulus: giving food. unconditioned response: salivating conditioned stimulus: ring bell conditioned response: salivate due to bell

bipolar vs unipolar depression

unipolar (major depression) affects 1/5th population, usually onset 25yrs. bipolar depression (depression + mania) affects <1% population, usually onset 30yrs old

how do unipolar, bipolar, and non-depressed people differ in their reaction times to happy/sad words?

unipolar are quicker at sad words, bipolar quicker at happy words, control subjects were equal at both.

what is the gender ratio of the effects of depression?

unipolar is 2:1 females:males, and bipolar is equally common in both genders

what are the causes of schizophrenia?

unknown - has many associated genes, could be viral, must be involved in adolescent development

what is sleep for?

unknown - likely to be restorative. adjusts muscle tension/brain metabolism/body temp. sleep deprivation leads to serious cognitive + physiological disturbances

what is pain

unpleasant emotional and sensory experience associated with actual or potential tissue damage, or described in terms of such damage

does the corticospinal tract contain lower or upper motor neurones?

upper

is babiski sign present in upper or lower motoneuron lesions?

upper

how are tendon reflexes affected in upper and lower motoneuron lesions

upper lesions = hyperreflexia, lower lesions = hyporeflexia/areflexia

how is muscle tone affected in upper + lower motor neuron lesions

upper lesions there is a spastic (spasming) tone, lower lesions there is a flaccid tone

scala vestibuli

upper perilymph-filled bony cavity inside the cochlea. conducts sound vibrations to scala media. extends from the vestibule of the ear to the helicotrema where it joins scala tympani

How do GPs diagnose depression?

use a *patient health questionnaire* for major depression, but for bipolar depression you use *mania symptoms* (abnormally high mood etc)

analgaesic

used for relief from pain

lancaster-regan chart

used to detect astigmatism of lens.

function of premotor cortex

uses spatial and sensory cues to execute movement and planning *visually guided voluntary movements*. also projects to spinal cord - possibly involved in behaviour

optogenetics

using genetic mechanisms to modify the CNS so that neurons can be activated by light

describe clinical patterns of MS over time

usually first shows between 20-40, then relapsing then remitting whilst progressing, with complete or incomplete remission.

how do calcifications appear in the brain?

usually located in the basal ganglia, glands, vessels/plexuses eg choroid plexus

name 5 main causes of painful visual loss

uveitis, acute angle closure glaucoma, keratitis, optic neuritis

diazepam is aka

valium

what creates eye colour?

variable amounts of eumelanin (brown/black melanins - more in brown eyes) and pheomelanin (red/yellow melanins - more in blue/green eyes) produced by melanocytes

choroid plexus

vascular CSF-producing structure, like a cauliflower perfused with blood, present in all brain ventricles -seen here superiorly within the 3rd ventricle

which causes more immediate motor loss, a tumour or a vascular occlusion

vascular occlusion

is the 'what' visual stream ventral or dorsal?

ventral - projects to temporal lobe

which 3 regions of the thalamus do the basal ganglia output to?

ventral anterior (VA), ventral laterall (VL) nuclei

which part of thalamus supplies PM and SMA?

ventral anterior nucleus

which part of thalamus is major input to primary motor cortex (M1)

ventral lateral nucleus

where do pelvic splanchnic nerves arise?

ventral rami of sacral spinal nerves S2, S3, S4

name the two pathways which each V1 transmits information to

ventral stream (or 'What' pathway) and dorsal stream ('Where' pathway)

what is the A10 nucleus?

ventral tegmental nucleus

how does hydrocephalus appear on a brain scan

ventricles are blown up, and CSF leaks into surrounding brain

which part of the hypothalamus contains sleep-promoting neurons?

ventrolateral preoptic nucleus

activity in which brain region induces sleep?

ventrolateral preoptic nucleus (sends suppressive projections to ascending arousal system)

aside from vertebrae, what else protects the spinal cord?

vertebral ligaments, meninges, fat, and cushioning fluid (CSF)

what travels through the C7 transverse foramen

vertebral vein and sympathetic nerves (vertebral artery goes *around* the foramen, not through)

subtarsal foreign body may present itself how in the eye?

vertical scratches around cornea which will show (with flourisine) as 'scribbles' on the eye surface from opening /closing eyelids

microscopic MRI

very high resolution MRI imaging (down to nanometer scale, in some cases comparable with histopathology)

post rotational nystagmus

vestibular nystagmus; occurs when the body is rotated and then the rotation stopped, due to *adaptation* of vestibulo-ocular reflex. If, while sitting in swivel chair, body is spun to the right, the nystagmus during rotation has its slow component to the left (eye tracking left, then jumping). When rotation stops, the slow component is to the right (feels like spinning the other way)

which reflex stabilises eye position in space during movements?

vestibulo-ocular reflex

which reflexes act to stabilise an image when there are head movements?

vestibulo-ocular reflexes

how do vestibulospinal reflexes differ from cervicospinal refelexes?

vestibulospinal involves (tilting of) head-neck - activating the vestibular receptors. cervicospinal detects only neck-neck movements via stretch reflexes in the neck.

how and why does the body sensitise + amplify pain after injury?

via *peripheral sensitisation* (plastic changes in C fibers amplify signals) and *central sensitisation* (same in dorsal horn). done so it hurts even more to touch skin. this protects the area whilst it heals

how can silent nociceptors be activated?

via the axon reflex; if inflammation occurs, the chemicals released by mast cells etc may activate nociceptors so they become painful

*how* is sound a pressure wave?

vibration of objects sets up pressure waves in the surrounding air, which propagate (because air has an 'elastic' property

viral conjunctivitis vs bacterial

viral = more common + more contagious, linked to flu-symptoms, watery dischange, can damage vision. bacterial = yellow green pussy discharge, crusting in morning, not affect vision.

which are spoken at a lower pitch and higher sound, consonants or vowels?

vowels (and sadly for hearing loss patients, consonants are more important for word recognition than vowels)

which is more efficient, human walking or running?

walking (75% more than running)

which structures are critical in causing declarative memory loss in medial temporal lobe amnesia

was thought to be hippocampus and amygdala, but recently shown to be *rhinal and perirhinal cortex*

vigilance

watchfulness; process of paying close and continuous attention

what features of lightwaves enable us to form different aspects of image

wavelength = colour, light/dark edges = contrast, spatial frequency = size

amantadine

weak antagonist of NMDA glutamate receptor, increases dopamine release, and blocks dopamine reuptake. weak treatment for parkinsons

is there muscle weakness in upper or lower motor neuron lesions?

weakness is shown in both, but in upper lesions it has a specific muscle distribution (pyramidal weakness) whereas in lower lesions it affects individual muscles controlled by the lower motoneuron

pyramidal weakness

weakness of specific muscles so that flexors in the upper limb are stronger than the extensors and the reverse is true in the lower limb. seen in upper motoneuron lesion.

what is the key side effect of atypical antipsychotics

weight gain

describe oscillatory activity in a two neuron loop

when an excitatory neuron links to an inhibitory neuron and they cyclicly act on each other, causing bursts of activity and silence

what is the recency/primacy effect in memory?

when asked to remember a list of words, people are best at remembering the first and last few words.

how does lack of light affect bipolar cells

when is light, photoreceptor cells hyperpolarise and release less glutamate. this stimulates ON bipolar cells and inhibits OFF bipolar cells

refractive disorder

when shape of the eye, shape of the cornea, or condition of the lens prevents light focusing on the retina properly.

occipital alpha rhythms are seen on an EEG when?

when subject has eyes closed but awake

what is reflex adaptation? do all reflexes show adaptation?

when the body adjusts its reflex response in a certain situation - eg while spinning in the baranyi chair with eyes closed, nystagmus of head adapts (decreases), leading to several seconds of post-rotational nystagmus. *not all reflexes do this*

lissaur's tract

when the spinothalamic tract neurons enter the spinal cord, they mostly decussate at level of entry, but some may first zip up or down a couple levels in *lissaur's tract*

describe phase locking of auditory nerve

where neurons only fire at the preferred stage of a sound wave cycle. Due to long refractory periods, having combos of neurons locked at different phases enables brain to detect *frequency*

where is the junction between the peripheral + central nervous system?

where the dorsal and ventral roots arise

how do you describe the distribution of Ia nerve fibres across intrafusal muscle fibres?

'flower spray endings'

what are T1 and T2 in MRI?

'time constants' - they can be set up for each scan as a sequence, and give different shades/intensity signals forvarious tissues

stereopsis

* perception of depth* produced by the reception in the brain of visual stimuli from both eyes in combination; binocular vision

what are the DSM-5 criteria of depression?

*(1 of first 2 necessary plus 4 others) for 2 weeks: *Dysphoria (i.e. reverse of euphoria / increased negative), Anhedonia (i.e. lack of positive), Sleep changes, Altered weight/appetite, motor changes, Fatigue, Worthlessness/guilt, Lack of concentration/decisiveness/interest, Suicidal ideation

name 3 types of ganglia which presynaptic sympathetic neurons synapse with?

*paravertebral ganglia* (R+L sympathetic trunks) or *prevertebral ganglia* (ganglia anterior to vertebral column, around the abdo aorta). also (sort of) the *adrenal glands*

name 3 diseases in which alpha-synuclein aggregates?

*parkinsons disease*, lewy-body disease, multisystem atrophy

which conditions cause cytotoxic cerebral oedema?

*trauma*, reye's syndrome, hypothermia, *early ischemia*, encephalopathy, cardiac arrest, pseudotumor cerebri

pain, epilepsy, anxiety - are these schizophrenia +ve or -ve symptoms?

+ve (they are all signs of a brain which is over active)

what value is the resting potential of most cells?

-70mV

is haemophilus influenzae gram - or +

-ve

depressions, parkinsons, alzheimers - are these schizophrenia +ve or -ve symptoms?

-ve (all signs of a brain which is less active)

what is the average auditory threshold for hearing sounds of frequency 1000 Hz in a young adult?

0dB

how many cones does each retinal ganglion cell connect to?

1 (each cone gets a ganglion cell entirely to itself, unlike rods)

what is the prevalence of schizophrenia?

1%

chant to remember reflexes

1, 2 buckle shoe (achilles), 3,4 kick the door (patella), 5,6, pick up sticks (biceps), 7, 8 lay them straight (triceps)

primary somatic sensory cortex contains which brodman areas?

1,2 and 3

what age does schizophrenia usually onset?

16-24yrs

each hippocampus connects to the contralateral hippocampus via what?

2 pathways, one through the hippocampal commissure, and one through anterior commissure

is MS more common in males or females?

2:1 females:males

how long do you have to have a pain for it to be chronic?

3 months

obesity is regarded as a BMI of over what?

30

what is the mean age of onset of MS

30years

how many pairs of nerves does the CNS consist of?

43. (12 pairs cranial nerves, 31 pairs spinal).

what is the incidence of meningococcal meningitis

5 cases, 100,000

what is the only ionic monoamine receptor

5HT3

what is the frequency of alpha waves

8-13Hz

audiometry checks hearing thresholds of sounds up to which frequency? why?

8000 Hz. (humans can supposedly hear up to 20,000, but the lower frequencies are most important in daily life)

primary hypertension accounts for what % of all hypertensive cases?

90% (it is aka 'essential' hypertension)

in parkinsons, loss of dopamine causes increase in which tremor-inducing chemical?

ACh

which single transmitter is pretty much the only one used in the motor nervous system

ACh

what is the most commonly found receptor in the nervous system?

AMPA receptor

if you give NA to a healthy patient, would you expect HR and BP to rise?

BP yes - but not HR because the baroreceptor reflex fires in response to raised BP, which slows the heart

what do the letters 'C', 'Fp' and 'Cz' stand for in EEG?

C: central, Fp: Frontal pole, Cz: vertex

which 3 DNA bases are in the trinucleotide repeat of the IT15 gene? how many times do they repeat?

CAG. In healthy people, they repeat <34 times. the more repeats *over* this, the more likely/severe the *huntingtons disease*

which areas of the brain are affected by the affective/cognitive dimesions of pain?

Anterior Cingulate cortex (ACC)

which dopamine receptors activate adenylyl cyclase?

D-1 and D-5

which dopamine receptors inhibit adenylyl cyclase?

D-2, -3, and -4

how do D1 and D2 receptors couple to adenyl cyclase?

D1 = positively coupled to adenyl cyclase, D2 = negatively

how does apomorphine enable parkinsons patients to move properly?

D1 and D2 receptor agonist (acts like dopamine to restore movement)

domperidone

D2 R antagonist which doesn't cross blood brain barrier into brain. antidopaminergic drug used in general to suppress nausea and vomiting (acting on CTZ), as a prokinetic agent and for promoting lactation

Ropinirole

D2 agonist sometimes used in parkinsons

all antipsychotics antagonise which receptors

D2 dopamine

why does loss of dopamine production cause motor symptoms of parkinsons

DA action on D1 receptors is needed to enable movement (direct pathway) and DA action on D2 is needed to inhibit unwanted movements (indirect pathway)

side effects of SSRIs include

GI, rash/tremor/uticaria, loss of libido

list factors which could cause brain oedema

Infarction ("ischaemic stroke")- Brain trauma- Abscess, purulent meningitis.- Hypoxemia- Hyponatriemia

causes of cytotoxic oedema

Ischemia (acute), Hyponatremia, Reye's Syndrome, purulent Meningitis

what is brodman area 6?

Premotor cortex and Supplementary Motor Cortex

give 6 symptoms of meningitis

Headache Photophobia Nausea/vomiting Neck stiffness (Rash) (Fever)

which are the biggest fibres involved in the muscle spindle system?

IA fibres

SNRI

Serotonin-norepinephrine reuptake inhibitors. antidepressants which inhibit reuptake or serotonin *and NA* from synapses

rarefactions

a decrease in the density of something, eg a soundwave or a tissue

paraesthesia

abnormal sensation, typically tingling or pricking ("pins and needles"), caused chiefly by pressure on or damage to peripheral nerves

what is the lifetime prevalence of depression?

about 25%

how might a brain stem lesion present in terms of *visual* symptoms

affecting eye motility; internuclear ophthlmoplegia, nystagmus

which systems form affective behaviour?

affective behaviour is formed by combined characteristic patterns of autonomic + somatic activity

which nerves supply the afferent and efferent limbs of the pupillary light reflex

afferent is within CN II (optic nerve). efferent within CN III (occulomotor).

type 1 synapses

aka asymmetric synapses. rounded vesicles in the presynaptic cell and a prominent postsynaptic density. typically excitatory + found between axons and dendritic spines

dorsolateral tract of lissauer

aka dorsolateral tract. strand of grey matter posterior to dorsal horn, associated with pain/temp and having many unmyelinated axons

Pick's disease

aka fronto-temporal lobe dementia. dementia which is more likely to affect behaviour/language/personality due to build up of tau proteins in frontal brain. often caused by mutation in MAPT (tau gene)

glia limitans

aka glial limiting membrane. thin barrier formed by astrocyte foot processes, surrounding brain and spinal cord, deep to the pia mater. prevents overmigration of neurons/neuroglia into meninges, and helps regulate molecule/cell transport along with blood brain barrier

neocortex

aka isocortex. largest part of the cerebral cortex (includes most of it except olfactory + limbic areas). has 6 layers.

spectogram

aka sonogram. visual representation of the spectrum of frequencies in a sound or other signal as they vary with time (eg you can 'see' pitch)

tentorial notch

aka tentorial incisure. the space in the tentorium through which the brainstem passes

function of pupil

allows light to enter eye

neuroleptics

another name for antipsychotics

what is the most common refractive disorder?

astigmatism

vestigial

atrophied / having become functionless in the course of evolution

BOLD-contrast imagine

blood oxygen level dependent imaging; method used in fMRI to observe areas of the brain which are *active* by identifying areas with *decreased* deoxyhaemoglobin than oxy-Hb

what does the cornea cover?

both the pupil and the iris (is then continuous with the *sclera* which covers the rest of the eyeball)

causalgia

burning pain in a limb along the course of a peripheral nerve; usually associated with skin changes

how is magnitude of a sensory stimuli encoded in the nervous system?

by AP *frequency*. (above a threshold of a stimulus pressing on skin, a sensory receptor potential excites a train of all-or-nothing action potentials, whose frequency varies with stimulus strength)

how are cutaneous mechanoreceptors classified?

by adaptation properties, structure, + location (superficial or deep).

what is the posterior boundary of the frontal lobe?

central sulcus

ACh is synthesized by which enzyme?

choline acetyl transferase

why are non-selective MAO inhibitors not preferred

choosing a selective MAO A or MAO B inhibitior preserves one MAO type to break down *tyrosine* (prevents hypertensive crisis)

describe the flow of CSF

choroid plexuses in lateral ventricles, interventricular foramen, 3rd ventricle, cerebral aqueduct, median+lateral apertures, subarachnoid space, (central canal etc), arachnoid granulations in superior sagittal sinus, bloodstream

3 'C's which you need to describe the optic disc

colour, contour, and cup-to-disc ratio (cup is central white portion)

are there more rods or cones in the fovea?

cones

lens accomodation

contraction of the ciliary muscles which relieves the tension on the zonule fibres, allowing the lens to become rounder due to its natural elasticity

pyramidal tract is AKA?

corticospinal tract (and some corticobulbar tracts)

why do you feel sick when your vestibular system and visual system are mismatched (eg seasickness)?

could be a reflex to do with certain edible toxins/poisons being associated with fever + dizziness.

what is the effect of isoflurane (and other halogenated anaesthetics) on sympathetic outflow?

decrease it

does L-DOPA therapy increase or decrease blood pressure? why is this surprising?

decrease. surprising because L-DOPA can be coverted to NA, so you would expect a sympathetic increase

amblyopia

decreased vision in an eye that otherwise appears normal, often due to 'turned off' visual processing in the brain. aka *lazy eye*

what is the pathogenesis of axonal damage

diffuse axonal injury eg brain trauma, tissue damage eg tumours, infarction

micturition

discharge of urine

3 neurotransmitters associated with schizophrenia

dopamine, seratonin, NA

naloxone

drug which blocks opiates receptors (given to addicts who overdose)

anxiolytic

drug which reduces anxiety

triptans

drugs which relieve pain in migraines/headaches

what does the word 'vestibule' mean

entrance chamber

firefly luciferase

enzyme which allows fireflies to produce light. binds *hydrophobic* molecules

what is RAPD in the eye

Relative afferent pupillary defect

how can you quickly determine whether a patients incoordinated movements are due to sensory ataxia or something else (like cerebellar pathway lesion)?

Rombergs sign: does patient lose their balance when they close eyes. if so, its sensory ataxia

plantar flexion reflex has which nerve roots?

S1

which part of the brain controls circadian rhythm

SCN (suprachiasmatic nucleus)

paroxetine

SSRI antidepressant, highly potent for blocking SERT

EC50

'effective dose' - the dose or amount of drug that produces the desired effect in 50% of the subjects taking it

prosopagnosia

'face blindness'. unable to recognise/perceive faces, while other aspects of visual processing and intellectual functioning remain intact

working memory

'ready to use' info - may be new sensory information, or info retrieved from long-term storage (episodic/semantic) ready to access (e.g. where you parked your car whilst in the supermarket).

egocentric space

'space as I see it' eg moving hand to the left (as opposed to allocentric space)

'angio-' means what?

'vessel'

william james

father of psychology; first hypothesised that memory involved carving out of 'brain-paths' by excitation in the brain

what does Beck's term 'Cognitive distortions' mean?

faulty logic, e.g. overgeneralisation, selectively filtering out positive information

mandibular nerve travels through which skull foramen

foramen ovale

where do the pyramids of the corticospinal tract split into bundles?

in lower pons

which cranial fossa does the brainstem lie in?

inferior cranial fossa

what does IT15 stand for?

interesting transcript 15

how is amphetamine related to ecstasy?

it is the parent drug

what does the amplitude of an EEG wave indicate?

large amplitude = synchronised neurone activity summating

where in brain are visual memories 'stored'

lateral temporal lobes

sensory ataxia

lesions of sensory nerves or pathways deprive the brain of proprioceptive/sensory info needed for coordinated movements. sufferers show a positive *Rombergs sign*

would there be more or less signal from the substantia nigra in a scan of a parkinsons patient?

less

is brain more or less active during sleep than when awake?

less active, except for REM sleep, when it is more active

in transverse sections of spinal cord, is white matter more or less in lower spinal sections?

less and less white matter relative to grey as you move down the spinal cord (because there are fewer ascending/descending pathways)

why does the STN increase its firing in parkinsons?

less dopamine means less firing of D2 receptors,

difference between hippocampus proper and hippocampus formation

"hippocampus proper" refers to the four CA fields, and "hippocampal formation" to the hippocampus proper plus dentate gyrus and subiculum

which has a better prognosis, supra- or infra-tentorial space occupying lesion? why?

supratentorial. there are more preceding signs (confusion/stupor/vomiting) than in infratentorial lesion (often produces coma without preceding signs)

supraventricular vs ventricular arrhythmias

supraventricular arrhythmias are either atrial or junctional; ventricular affect the ventricles.

How does MS present?

symptoms start typically between 20-40yrs old, separated in time and space. episodes of *numbness*/tingling/*pain* sensations. lhermitte's sign. optic neuritis/internuclear ophthlmoplegia. balance/speech/bladder erectile problems. *weakness, maybe worse after a hot bath*. depression, cognitive/memory problems.

phencyclidine

synthetic NMDA receptor antagonist, used as an anesthetic by vets; illicitly taken as 'angel dust' for its effects as a hallucinogen

methadone

synthetic narcotic drug similar to morphine but less habit-forming; used in narcotic detoxification and maintenance of heroin addiction

function of emotions

tell us what we want more/less of; we can make complicated decisions without having to reason things out

primary auditory cortex is in which lobe?

temporal

apnea

temporary cessation of breathing, especially during sleep

concussion

temporary unconsciousness after a blow to the head; mechanisms unknown - but some sort of 'brain shock'

preseptal cellulitis of eyelids

tender/warm erythematous upper + lower eyelid skin associated with cold/fever + common in children

what lies between the occipital lobes and the cerebellum?

tentorium cerebelli

psychic blindness

term used by researches in 1940s to describe monkeys with temporal lobe lesions who kept picking up inedible objects to their mouths - due to damaged visual pathway object recognition

what does the nernst equation calculate?

the reversal (aka equilibrium) potential of an ion

is the red nucleus in the midbrain, pons, or medulla

the rostral midbrain

blood/air coefficient is AKA

the solubility of a gas in blood

which areas of the brain are affected by the discriminative dimension of pain?

the somatosensory cortex

second order somatosensory neurons terminate where? what do they synapse with?

the thalamus (mosly *ventral posterior nucleus*) to synapse with 3rd order neurons which run to the somatosensory cortex

why is healing minimal in osteoarthritis?

the tissue which is damaged is cartilage; a tissue with little capacity to heal itself

how are ACE inhibitors teratogenic?

they cause renal damage in baby

how does deep brain stimulation treat parkinsons?

two deep stimulating electrodes create a tetanic block of action from subthalamic nucleus, preventing the STN from increasing the inhibitory drive on the thalamus from the basal ganglia outputs.

how do experiments prove that threat increases pain?

two patient groups have foot lasered. one group told it will be fine, another group told that 'the ethics board had some reservations with this, but we're doing it anyway.' 2nd group feel more pain

barbituate

type of CNS depressant drugs which can produce a wide spectrum of effects, from mild sedation to total anesthesia (eg thiopentone). not often first choice drugs (resp.depression, not analgesic, addictive, narrow therapeutic index, deadly)

transient global amnesia

type of amnesia produced by small interruptions in cerebral blood flow - involves short retrograde + anterograde amnesia for *minutes/days* (no permanent damage)

implicit memory

type of memory in which previous experiences aid in the performance of a task without conscious awareness of these previous experiences. includes procedural and emotional memory

name the rate limiting enzyme for NA synthesis?

tyrosine hydroxylase

autonomic dysreflexia

uninhibited and exaggerated reflex of the autonomic nervous system to stimulation - sudden high BP - medical emergency. often seen in patients with spinal injuries above T6

give some somatic symptoms of depression

unintentional weight change, fatigue, (appetite/sleep disturbance), aches&pains

why are C nerve fibres so slow at impulse conduction?

unmyelinated, small diameter

does the switch from conscious to unconscious occur over a wide or narrow concentration range of anaesthetics?

very narrow concentration range. the concentration-response curve is very steep for anaesthetics compared to other drugs

what has amphetamine got to do with dopamine?

very potent dopamine releasing agent; 'dopamine pours out into brain.'

tritanopia

very rare colour blindness in which there are only two types of cones present (no blue cones) in the retina, causing green/blue confusion

does schizophrenia lead to split personalities?

very rare to lose sense of own identity.

VMAT2

vesicular monoamine transporter. integral membrane protein that transports monoamines (DA, NA, 5HT, H) from cellular cytosol into synaptic vesicles

inferotemporal cortex is associated with 'storing' what kind of memories?

visual memories, eg identifying objects and faces

the action potential threshold is reached *when*?

when Na+ influx > resting K+ efflux, and depolarisation due to Na+ influx is sufficient to activate neighbouring Na+ channels

is capsula interna white or grey matter

white

do veins have sympathetic tone?

yes (in fact it is quite substantial - is what prevents postural hypo-tension)

will an unconscious patient have a pupillary light reflex?

yes (unless their brain has swollen or brainstem damaged)

is huntingtin protein found in healthy people?

yes - it is important in healthy life, though if mutated, it is the protein which causes huntingons

can amnesia patients be classically conditioned?

yes - not impaired on skill memory/priming tasks

is the mammillary body a paired structure?

yes - there are two just posterior to infundibulum

is it possible for radial glial cells to undergo symmetrical division?

yes - they can just form two more RGcells. however, importantly, they can undergo asymmetric divisions.

is depression heritable?

yes - unipolar is 30 to 50% heritable, and bipolar is around 80% (similar to schizophrenia)

are strong opiods effective at treating cancer pain?

yes they are largely effective (not as effective as in acute pain, however).

is CBT a recommended treatment for pain?

yes, cognitive behavioural therapy is recommended as first line treatment in chronic pain

are mechanoreceptors, thermoreceptors, and nociceptors myelinated?

yes, except C fibre nocicptors

is it possible to have a negative auditory threshold?

yes, in better than average hearing - points plotted at -5 or -10dB mean you can hear quieter sounds than the average population used to create the ISO (which calibrates a 'normal' threshold seen at 0dB.)

does location affect severity of drug withdrawal?

yes, in places associated with drug, addicts will have worse withdrawal symptoms

are AChE inhibitors used in closed-angle glaucoma?

yes, they can be in both, as they act to constrict pupil. it is a2 agonists (epinephrine/diperiprine) which you would contraindicate in closed-angle glaucoma, as they are mydriatic so would worsen closed angle

can fruit flies be trained?

yes, they can learn by classical conditioning

why does opening more ion channels in a membrane decrease resistance of that membrane?

you can think of it as the resistance of the membrane to passage of ions - opening more channels will decrease this resistance.

why do you get *dose escalation* and *addiction* with barbituates

you develop metabolic tolerance to barbituates

where do you find fibroblasts/collagen in the CNS?

you don't

what is different about the nernst equation with negative ions rather than positive?

you take ln(inside conc of ion/outside conc of ion)

how can you tell whether sounds come from left or right, front or back?

your brain uses the time delay between sounds hitting your right ear to your left to decide whether sound comes from L/R. front and back sounds hit both ears at the same time - pinna is shaped to help distinguish them

lenticulo-striate arteries

~10 long penetrating arteries which branch upwards from the initial part of the MCA, supplying basal ganglia + much of internal capsule. sensitive to rupture/obstruction, leading to sterotyped stroke symptoms

how many muscle spindles in the body?

~20,000

what is intracellular pH?

~7.2

how often does the olfactary bulb regenerate?

~once a month (one of only areas of continuous neuroregeneration)

what are class II anti-dysrhymic drugs? give examples

β-blockers. metoprolol, timolol, propanolol, alprenolol

what does GABA stand for?

γ-aminobutyric acid

retrograde amnesia

loss of memory for events *prior to the trauma*

name the region of greatest visual acuity in the eye

macula

why do you get vein occlusions?

mainly due to high BP causing arterioles to become thickened/ridged. arterioles then press onto veins

dorsal column decussate at the medulla or the level of spinal cord?

medulla

prestin

motor protein of the outer hair cells of cochlea. it changes shape as the voltage around it changes - causing whole cell to change in length

nasal hemi-retina

nasal half of the retina

can you see the pterygoid canal in a skull?

no (hidden from view) but it can be seen in a disarticulated sphenoid bone

2 main causes of dry eyes

not producing enough tears, or rapid evaporation of tears (due to not enough secreted lipid from glands)

which mesodermal structure is involved in 'telling' the ectoderm to form the nervous system/morphogenesis of spinal cord?

notochord

primary visual cortex is in which lobe?

occipital

what % of parkinsons patients have a mutation which causes parkinsons?

only 10% (rest of patients we don't know the cause)

how many axons can a single neuron have?

only ever *one*. (this may have collaterals which contact many other

is the fasciculation in upper or lower motor neuron lesions?

only lower

which receptor does morphine bind to?

opioid receptors, particularly μ-opioid receptors

the circle of willis surrounds what?

optic chiasm

where do fibres from the nasal retina decussate?

optic chiasm

blood vessels radiate from which part of the retina?

optic disc

origin and insertion of ciliary muscle

origin: scleral spur(longitudinal fibres)/root of iris(circular fibres). attach the end of ciliary processes/root of iris.

tectospinal tract

originates in superior colliculus of midbrain tectum. controls movements of the head/neck/eyes at the level of C1 vertebra, in response to visual/auditory stimuli

if a fracture of petrous temporal bone occurs, would you expect rhinorrhoea or otorrhoea?

otorrhoea (leakage from the ear) potentially of CSF which escapes into ear through any cracks

which cells help amplify vibrations of the basilar membrane?

outer hair cells

which ear hair cells function to enhance sensitivity to sound?

outer hair cells

what pathology could give rise to a 'sympathetic overdrive' seen in a patient?

over-production of adrenaline by Pheochromocytoma (type of adrenal gland tumour)

what causes compulsive behaviours as a side effect of parkinsons treatment?

overactive reward system caused by treatment which increases dopamine

allodynia

pain due to a stimulus which does not normally provoke pain. Temperature or physical stimuli can provoke allodynia, and it often occurs after injury to a site

neuropathic pain

pain generated by lesion or disease to nervous system (usually somatosensory system)

gate control theory of pain

pain is influenced by ascendingna dn descending influences, controlled by the spinal chord

difference between pain and nociception

pain is the *percept*, nociception is what pain receptors detect

silent nociceptors

pain receptors which only respond to mechanical stimuli when inflammatory molecules are present

what important difference should doctors remember about difference between painful and painless visual loss?

painful = usually 2nd to vascular events, whereas painless is usually 2nd to inflammatory events

anterior ischaemic optic neuropathy

painless loss of vision due to damage to the optic nerve from insufficient blood supply

is central retinal artery occlusion painful or painless?

painless visual loss

which bone is found deep within the pterygopalatine fissue

palatine bone

Edinger-Westphal nuclei

parasympathetic pre-ganglionic nucleus that innervates the iris sphincter muscle and the ciliary muscle. aka 'accessory oculomotor nucleus'

primary somatosensory cortex is in which lobe?

parietal

optic ataxia is associated in lesions where in the brain?

parietal cortex

primary visual cortex

part of occipital lobe, responsible for first processing visual information. one on each side - deal with R and L visual fields respectively. cortical blindness if loss of both.

anterior spinocerebellar tract

part of the somatosensory system ; runs parallel to posterior spinocerebellar tract, up the lateral outer edge of spinal cord. conveys unconscious proprioceptive info from the body to the cerebellum

amnesia

partial/total loss of memory due to damage to medial temporal lobes / limbic system

modality

particular mode in which something exists or is experienced or expressed

what is affective behaviour?

pattern of behaviour that is elicited by "emotions" such as fear, rage, surprise, disgust, anxiety, euphoria, pleasure, sadness et

dissociated sensory touch

pattern of neurological damage caused by a lesion to a single afferent tract - involves selective loss of fine touch and proprioception without loss of pain and temperature, or vice versa

streptococcus pneumoniae is aka?

pneumococcus

what does PM stand for in the brain?

premotor area

which cortex is located in the precentral gyrus?

primary motor cortex

what is function of brodmann areas 1, 2, and 3

primary somatosensory cortex - main sensory receptive area for sense of *touch*. receives from thalamus, processes info, sends to somatosensory association cortex

thrombolysis

process of breaking up and dissolving blood clots

why is 50% N2O given to women during childbirth?

produces analgesia and slight anaesthia

tau protein

proteins that stabilize the microtubule cytoskeleton, abundant in the CNS. if hyperphosphorylated, form tangles of filaments (NFTs), which lead to neurodegenerative diseases, mainly alzheimers

which are found nearer the midline, the motor neurons for proximal structures, or for distal structures?

proximal

difference between psychological and physical drug dependence

psychological affects mood / behaviour, physical affects somatic physiology

the pterygoid canal and foramen rotundum both lead from the posterior sphenoid bone, right through the sphenoid into the?

pterygopalatine fossa

which have capsules, slow or rapid adapting mechanoreceptors?

rapid (eg pacinian and meissner corpuscles)

paroxysmal disorder

recurrent, episodic condition eg narcalepsy, epilepsy, migraine

circadian

recurring naturally on a twenty-four-hour cycle, even in the absence of light fluctuations

conjunctivitis

red inflammation of the conjunctiva, caused usually by adenovirus or sometimes bacteria (if the latter, there will also be sticky pus)

central sleep apnea

reduced central respiratory drive to the diaphragm during sleep. Reduced muscle tone in non-REM sleep leads to reduction of airways. resulting hypoxia + hypercapnia wake the patient

fixation reflex

reflex concerned with attracting the eye on an object. For example, when a light shines in the periphery, the eyes shift gaze on it

frontal eye field

region in frontal cortex called Brodmann area 8 which communicates with extraocular muscles. reponsible for saccadic eye movements for visual field perception, and for voluntary eye movement

ventral striatum

region of brain involved in 'prediction error' - releases phasic dopamine bursts which correlate with people discovering that something they believed is not true - eg the sweets are no longer in same place in supermarket

intermediolateral cell column

region of gray matter found in Rexed lamina VII of the spinal column, which forms the lateral horn

tegmentum

region of gray matter on either side of the cerebral aqueduct/running down the brainstem

Wernicke's area

region of the brain concerned with the comprehension of language, located in the cortex of the dominant temporal lobe

wernike's area

region surrounding auditory cortex; involved in understanding the 'meaning' of words. confined to the left (dominant) hemisphere

define: reticulate

resembling or forming a network

phenotolamine

reversible nonselective alpha-adrenergic antagonist

which is more sensitive to photons, rods or cones?

rods

what are SA2 receptors?

ruffini endings: deep mechanoreceptors

give some behavioural symptoms of depression

self-neglect, sleep disturbance, psychomotor agitiation/retardation (low motivation)

give 3 main functions of the enteric NS

sense changes in lumen/distension, control contract/relax/peristalsis for movement of gut contents, control absorption/secretion.

anti-tussive

stops coughing

heteroporia is AKA

strabismus

intraparietal sulcus

sulcus on postero-lateral brain: divides parietal lobe into superior and inferior nodules. involved in visual and numerical abilities

where are Mu-opioid receptors found on the spinal cord?

superficial dorsal horn - specifically the substantia gelatinosa seen in yellow

which theory explains why in amnesia (hippocampal damage), semantic memories are often spared over episodic memories? why?

*multiple trace theory.* semantic memories are used often (encoded many times) compared to the one trial encoding of episodic memory, hence semantic are more linked to the cortex and protected in hippocampal damage

radiculopathy

*nerve root* damage results in pain, weakness, numbness, difficulty controlling specific muscles... all in the region of that nerve distribution

entrapment neuropathy

*peripheral nerve* damage (by ribs or fibrous bands etc) results in pain, weakness, numbness, difficulty controlling specific muscles... all in the region of that nerve distribution

hyperopia

*refractive disorder*. (farsightedness): difficulty in seeing close objects clearly

myopia

*refractive disorder*. (nearsightedness): difficulty in seeing distant objects clearly

astigmatism

*refractive disorder*. blurring of vision caused by a cornea that is oval shaped, rather than round. Often found in conjunction with cases of myopia or hyperopia

presbyopia

*refractive disorder*. means "old eye". reduced elasticity of the lens due to normal aging process. affects ability of the eye to focus on close objects

why do APs only propagate in one direction?

*refractory period.* Na+ channels inactivate briefly after being opened, which means the membrane behind the action potential won't be activated by the local ion/voltage changes. also, this previous membrane is hyperpolarised by a K+ efflux after AP, so threshold is further to reach.

name 5 atypical neuroleptics

*risperidone*, Clozapine, Paliperidone, Olanzapine, Qietiapine

what are the 3 dimensions of pain

*sensory/discriminative* - quality + location. *primary affective/cognitive dimension* - unpleasantness, distress, fear, want it to stop *secondary affective/cognitive dimension* - anxiety + depression

name some supraventricular arrythmias

*supraventricular tachyarrhythmias* (SVTs) eg sinus tachycardia, atrial ectopic beats, atrial tachycardia, atrial fibrillation, wolff-parkinson-white, lown-ganong-levine. *(SVBs)* eg atrial sinus bradycardia, 1st, 2nd, 3rd degree atrioventricular block

define *borderline* hypertension

*sustained* bp > 140/90 mmHg

define *benign* hypertension

*sustained* bp > 160/100 mmHg, with no clinical features

list 7 *physical* symptoms of clinical depression

- Altered sleep: insomnia or increased sleep - Changes of appetite/weight - Fatigue / lethargy - Headaches - Unexplained aches or pains - Reduced libido - Digestive problems e.g. constipation

list 4 *cognitive/behavioural* symptoms of clinical depression

-Increase in negative/suicidal thoughts - Difficultly concentrating/remembering/making decisions - Anhedonia - Withdrawal from social activities

list 4 *emotional* symptoms of clinical depression

-Long-lasting low mood - Feelings of worthlessness, hopelessness, helplessness, guilt, regret, self-hatred - Low confidence / self-esteem - Anger / irritability

name the 5 key dopamine pathways

1. Nigro-striatal; A9 - caudate/putamen (motor function) 2. Mesolimbic; A10 - nucleus accumbens (reward) 3. Mesocortical; A10 - frontal cortex (psychosis) 4. Median eminence; pituitary (prolactin secretion) 5. Chemoreceptor trigger zone (CTZ) (vomiting)

how long from diagnosis do most MND patients live for?

1-5 yrs (mind you, stephen hawking managing over 50 yrs!)

how long after onset will MS patients require assistive walking device

15 years

what is the minimum % of O2 required in inspired air

15%

how many dendritic spines are on each MSN?

15,000

normal pressure of CSF

18mm

Vaughan-williams classification

1970s classification of antidysrhythmic drugs, with classes from I to IV based on their effects. sadly is a bit old now; many drugs span multiple classes

below T6, there are how many dorsal column tracts each side of the spinal cord?

2

how many ACh molecules bind to a nicotinic receptor to open it?

2

what kind of nuclei are contained within the colliculi on the dorsal midbrain?

2 superior colliculi = visuo-motor nuclei. 2 inferior colliculi = auditory relay nuclei

antihistamines bind to which receptors? what does this do?

2 types of antihistamines: either block H1 to treat allergies/insomnia, or H2 to block gastric acid secretion from parietal cells

what percentage of people with depression attempt suicide? what percent succeed?

20% attempt, 5-10% succeed (some use their medication)

paravertebral ganglia

23 paired sympathetic ganglia either side of the spinal cord, aka the sympathetic chains/trunks.

thalidomide taken during which days of gestation was most likely to cause phocomelia maximal?

24-27 days

how long after onset will MS patients lose ability to walk?

25 years

internal arcuate fibres

2nd order neurons that arise in the cuneate and gracile nuclei and pass across the midline of the medulla oblongata. once decussated, they are renamed 'the medial lemniscus'

what are the divisions of the ANS?

3 divisions - enteric, sympathetic, parasympathetic

the VPL projects to which brodmann areas?

3, 1 and 2 (primary somatosensory cortex)

P type cells feed into which layers of the lateral geniculate nucleus?

3,4,5 and 6

what percentage of osteoarthritis sufferers feel knee pain?

39% with grade 2 OA, 61% with grade 3/4 (pain is not inevitable feature of OA)

what is the normal white cell count of CSF

4

what % of schizophrenia patients attempt suicide?

40%

what is the fatality of meningococcal meningitis?

5% if in meninges, 20% if causes meningococcal bacteraemia, in which case is 20%)

neurons of the raphe nuclei contain which neurotransmitter?

5-HT

Buspirone

5-HT1A agonist used mainly in USA which has antidepressant and maybe some anti-anxiety effects. takes weeks to see its effect

roughly what % of all axons in CNS cross the midline?

50%

basal ganglia haemorrhage is commonly caused in which age group?

50s - 60s (by hypertension)

Alzheimers disease is what percentage of dementia cases?

55%

are 5HT receptors ionotropic or metabotropic?

5HT1 and 2 are *metabotrophic*, 5HT3 is *ionotropic*

which is better, 6/6 vision or 6/12?

6/6 (means you could read up to the '6m' line on snellen chart, rather than the '12m' line)

temazepam effects wear off after aprrox how low?

8hrs

what % of basal ganglia neurons are GABAergic?

99%

how can oligoclonal bands be used to test for MS?

>90% of MS patients, the CSF contains oligoclonal bands *not present in blood serum*.

which fibres cause you to immediately withdraw from a very hot stimulus

A-delta sensory fibres (the fast nociceptive fibres)

paracentral lobule

A gyrus on the upper medial surface of each cerebral hemisphere, behind the medial frontal gyrus and above the cingulate gyrus. forms the continuation, from the lateral brain surface, of the motor + sensory gyri: contains cortical areas representing the lower leg, foot, toes, bladder, rectum, and genitalia

what parts of the homunculus does the middle cerebral artery supply?

everything except lower limb

hyperaemia

excess of blood in the vessels supplying an organ or other part of the body

narcolepsy

excessive daytime sleepiness where there may be attacks of REM sleep/cataplexy, caused by reduction in hypothalamic orexin neurons

Aneurysm

excessive localized enlargement of an artery caused by a weakening of the artery wall

obstructive sleep apnea

excessive relaxation of pharyngeal muscles occludes the airways, especially in overweight men

neoplasia

excessive, uncontrolled growth of tissues, forming benign or malignant tumour(s)

does the striatum receive excite or inhibitory input from cerebral cortex?

excitatory

is substance P peptide excitatory or inhibitory neurotransmitter?

excitatory

difference between gray type I and II synapses?

excitatory (gray type I) is much darker and more fuzzy due to glutamate receptors, with characteristic spherical vesicles. inhibitary (gray type II) is thinner with vesicles of different shapes eg cylinders

perforant path

excitatory pathway from mainly layer 2 *entorhinal cortex* to dentate gyrus and CA3 of *hippocampus*. important in spatial memory learning, memory consolidation

in general, do activated alpha and beta 1 receptors have excitatory or inhibitory effects?

excititary

what is the function of brodmann area 4

execution of motor commands

is there risk of addiction giving opiates to chronic pain patients?

experimentally, it seems that the rewarding effects of opiates disappear when pain is present - so it seems that there is little risk.

medical name for a stye

external hordeolum

function of rubrospinal tract

extrapyramidal (involuntary) movement - eg coordination

reticulospinal tract

extrapyramidal descending tract from reticular formation, important in postural/locomotive control of upper body

vestibulospinal tract

extrapyramidal motor tract from vestibular nuclei in brainstem to ipsilateral muscles. involved in posture and balance.

4 main ions involved in resting membrane potential

K+, Na+, Cl-, and to an extent Ca2+

what are class III anti-dysrhymic drugs? give examples

K+channel blockers. amiodarone, sotalol

chorea can be a long term side effect of which drug?

L-DOPA

dystonia can be a long term side effect of which drug?

L-DOPA

levodopa is aka?

L-DOPA

which drug is normally used to treat parkinsons

L-DOPA

verapamil

L-type calcium channel blocker used to treat hypertension, angina, arrhythmia, migraine

knee extension reflex has which nerve roots?

L3,L4

laterodorsal tegmental nuclei

LDT nuclei: found in the tegmentum of the brainstem. Send cholinergic neurons to many forebrain targets eg thalamus, involving them in alert/attentiveness, and generate REM sleep

which is more soluble in blood, isoflurane or nitrous oxide?

isoflurane (N2O not very soluble in blood)

which factors could cause an obstruction in intracranial CSF drainage

Circulation: obstructive tumour, resorption- Malresorptive: haemorrhage, meningitis, high CSF protein

name the chief inhibitory neurotransmitter in humans

GABA

describe the grades of opiate abstinence

*from 0 to 3.* grade 0: drug craving/seeking/anxiety. 1: yawning/sweating/runny eyes+nose/restless sleep. 2: pupil dilation/gooseflesh/twitching/hot+cold flushes/shivering/aching/no appetite 3: insomnia/fever/high HR+BP+resp rate/abdominal cramps/vomiting/diarrhoea/weakness/weight loss

EGFR

(Epidermal growth factor receptor). Cell surface receptor which when mutated into overexpression, leads to uncontrolled cell division + cancer

give the 3 causative agents you would predict in a cause of neonatal meningitis

(GEL) group B streptococcus, listeria monocytogenes, E.Coli

IDH

(Isocitrate dehydrogenase). key enzyme in part of krebs cycle which when mutated, causes methylation of DNA histones, causing epigenetic changes linked to certain brain tumours.

which 2 structural features increase potency of anaesthetics

*halogen substitution* and presence of an *ether group*

name 5 bacteria which commonly cause meningitis

(SMILE) streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae, Listeria monocytogenes, Mycobacterium tuberculosis

describe how exciting D1 neurons increases firing rate of thalamus

*increases* firing of D1 neurons --> more inhibitary drive on the internal globus palludis/substantia nigra --> less inhibitory drive from these places to the thalamus. (*disinhibition*)

what were intravenous anaesthetics developed for

*induction* of anaesthesia

cranial (so parasympathetic) preganglionic neurones travel with which cranial nerves? what are their targets?

*Vagus (X)*: lungs, heart, stomach, small intestines, liver- *Occulomotor (III)*: pupil size, lens strength- *Facial (VII)*: salivary glands- *Glossopharyngeal (IX)*: smooth muscle + glands of throat, viscera of thorax + abdomen

which kinds of agents usually cause meningitis?

*bacteria,* viruses (*enteroviruses*), fungi (cryptococcal neoformans. can be non-infectious - cancer, autoimmune (SLE)

3 main types of sensory input to the spinal cord

*cutaneous* eg touch, pain. *proprioceptive* eg muscle length. *visceral* eg enteric pain, arterial O2.

name 6 inhaled anaesthetics used today

*desflurane, sevoflurane, isoflurane, nitrous oxide*, halothane, enflurane

difference between direct and indirect pathway in connects of the striatum

*direct* produces movement (inhibits the inhibitors of thalamic neurons) + goes via the medial part of the globus palludis. indirect inhibits movement (activates inhibitors of thalamic neurons) + goes via the external globus palludis and subthalamic nucleus

how do you classify symptoms of psychosis?

*+ve (type 1) symptoms* eg auditory hallucinations, thought disorder, delusions, thought broadcasting. *-ve (type 2)* eg lack of drive, withdrawal, catatonia. *also impaired cognition* eg working memory/planning/problem solving

how do CPGs produce an alternating action?

*Central Pattern Generators* produce rhythmic patterned outputs without sensory feedback. is thought that two spinal neurons are interconnected with inhibition from each to the other; one inhibits the other until it 'runs out', at which point the other inhibits the first one until that runs out

CTZ

*Chemoreceptor trigger zone*; area of the medulla that receives inputs from blood-borne drugs/hormones. communicates with the *vomiting center* to initiate vomiting

difference between learning, memory, and retrieval?

*Learning* is the acquisition of new information/knowledge. *Memory* is the retention of learned information. *Retrieval* is necessary to recall stored memories.

how long does it take from light hitting retina to form a visual percept in visual cortex?

100 mseconds (quite slow for neurological time - hence we have alternate reflex pathways)

a 20 decibel increase = what increase in power?

10x power (relative loudness) increase.

what % of UK GP consultations are related to eyes?

1.5%

break down the proportions of depression sufferers which do/don't respond to drug treatment. how does this change in relapses?

1/3rd respond to 1st line treatment, 1/3rd response to something else eventually...and 1/3rd don't respond. each relapse, responsiveness decreases

what % of MS patients remain unimpaired without therapy for 20years after onset?

10 - 20%

which cranial nerves originate in the brainstem?

10 of the 12 pairs; III to XII.

what amount of alcohol can be teratogenic?

10 units per week - or a single binge - can cause foetal alcohol syndrome

how long after onset will MS patients lose job

10 years

which has larger diameter, Aα or Aβ fibres?

Aα

describe PNS afferent sensory fibres (the 4 classes)

Aα - large fibres from proprioreceptors, Aβ - smaller fibres from skin mechanoreceptors: touch, Aδ - even smaller fibres from fast pain/temp receptors, C - tiny fibres carrying pain, itch, temp

types of Ia (primary afferent) fibres

Aβ fibres, Aδ fibres, C fibres

which conduction velocity class of fibre are thermoreceptors?

Aδ (A-delta)

subgenual anterior cingulate cortex

Brodmann area 25. part of cortex in which increased AND decreased activity has been linked to depression - many serotonin receptors found here.

give 6 types of anti-anxiety drugs

Bromides, antidepressants (SSRIs), sedative/hypnotics (Alcohol, Chloral hydrate, Pentobarbitone, Meprobamate, Benzodiazepines)

what info does a lumbar puncture give?

CSF pressure, presence of blood (sub-arachnoid haemorrhage), infection, immune diseases eg MS, tumour cells

which uses more ionising radiation, CT or MRI?

CT (MRI uses no ionising radiation)

which enables you to see calcifications in vessels, DSA or CT angiography?

CT angiography

what are the limitations of MRI?

CT better for bone• Pacemakers & ferromagnetic implants contraindicated• Claustrophobic & noisy• Not as readily available & more expensive that CT.

which tools do we have for brain imaging

CT-MR-Angio, Conventional MR, DWI, fMRI

which of these ions are more concentrated outside the cell than inside: Ca, K, Na, Cl?

Ca, Cl and Na

what are class IV anti-dysrhymic drugs? give examples

Ca2+channel blockers. verapamil, diltiazem

give 2 Anti-dysrhythmic drugs which *aren't* in the Vaughan-William's classification

Cardiac glycosides (digoxin) and adenosine

what does CT stand for in CT scan

Computerised tomography

functions of the ANS

Control the activity of the internal organs, blood vessels and superficial structures in the skin• Maintain the internal body environment, responding to internal + external changes

problematic effects of L-DOPA

Dyskinesia• On-off effects• Psychosis• Nausea• Reduced prolactin

Full visual field

FVF: the whole area viewed by the eyes

benefits of atypical neuroleptics

Fewer EPS, reduce both Positive AND negative symptoms, help drug-resistant psychosis, Less tardive dyskinesia

what is the fastest acting 'emergency' diuretic used in hospitals?

Furosemide

describe the anatomical steps in the pathway for memory formation from the hippocampus

Hippocampus > fornix > mammillary bodies > anterior nucleus of thalamus > cingulate cortex

what does MHRA stand for?

Medicines & Healthcare products Regulatory Agency (government body)

name 5 anxiety disorders

Panic disorder (debilitating fear attacks), phobia, Obsessive Compulsive disorder, Post-traumatic stress disorder (PTSD), Acute stress disorder, Generalized Anxiety Disorder

which famous patient reinforces the notion that episodic and semantic memory are distinct in the brain? how?

Patient K.C. After motorbike accident, has severe amnesia, in which he can remember facts but not events in his life, and can't imagine the future

what are brain seizures

Prolonged synchronous discharge of large numbers of neurons, as seen repeatedly in epilepsy. may be general seizures (involve whole brain) or partial

which pathway is the major nociceptive pathway

Spino-parabrachial nociceptive pathway

VEP

Visual Evoked Potential, useful test for MS and optic neuritis. record potentials from occipital lobe *in response to a stimulus* eg chequerboard (like an EEG, but evoked potentials, not spontaneous).

which two structures mainly function to *focus* light onto the retina?

cornea and crystalline lens

the iris is sandwiched between which two layers

cornea and lens

conus medullaris

conical lower extremity of the spinal cord, near L1-2

pink eye is AKA

conjunctivitis

function of horizontal cells of retina

connect photoreceptors across the retina to pool them (so that in dark, you can use *groups* of photoreceptors to increase signal strength, at the cost of resolution)

what is the dorsal column/medial lemniscus system?

conscious ascending pathway; carries sensory info of fine touch (tactile sensation), vibration + proprioception. In the spinal cord, sensation travels via the dorsal columns (fasciculus cuteatus&gracilis). In the brainstem, it is transmitted through the medial lemniscus

explicit memory

conscious, intentional recollection information 'you know that you know' - eg as remembering the time of an appointment. AKA declarative memory

describe the descending vestibulospinal system

consists of *lateral vestibulospinal tract* (fast acting - helps us walk upright) and *medial vestibulospinal tract *(slower - affects head movements)

ocular tremor

constant microtremor of healthy eyes, necessary to prevent fading of stabilised images

describe the outer segment of photoreceptor cells?

contains a stack of membranous disks which contain light sensitive photopigments for absorption (cones have less disks than rods)

how is ventral striatum involved in depression and manic depression?

contains nucleus accumbens/reward system. decreased in major depression, increased in manic depression

function of precentral gyrus

contains primary motor cortex, highest level in brain for control of movement. mainly controls contralateral side

function of postcentral gyrus

contains primary somatosensory cortex; consciously perceives the modalities of touch, temp, pain and pressure from contralateral body

which factors affect pain processing within brain to give different pain experiences?

context of pain - beliefes, expectation, placebo. mood - depression, anxiety. cognitive set - hypervigilance, distraction, catastrophizing. chemical&structure - neurodegeneration, maladaptive plasticity

what causes phantom limbs

continued activity in the area of somatosensory cortex where the limb used to input

athetosis

continuous succession of slow, writhing, involuntary movements of the hands and feet. a result of basal ganglia disorder

which increases outflow of aqueous humour into the canal of schlemm, contraction or dilation of ciliary muscle?

contraction

do unilateral lesions of basal ganglia lead to ipsilateral or contralateral motor disorders?

contralateral

major function of corticospinal and corticobulbar tracts

control of fractionated (skilled voluntary) movements eg of the hands or vocal cords

which lense corrects presbyopia?

convex lense

'kera-' refers to what in the eye?

cornea

what is the first and most powerful lens of the optic system?

cornea

name the collagen fibrils surrounding each individual peripheral neuron

endoneurium

what might you look for in brain scan for huntingtons disease?

enlarged anterior horn of lateral ventricles, shrunken caudate/putamen

bouton

enlarged part of a nerve fiber or cell, especially an axon, where it forms a synapse with another nerve

name 4 viruses which cause meningitis

enteroviruses, mumps, Lymphocytic choriomeningitis virus, (HIV)

where does the perforant path originate?

entorhinal cortex, layer 2

hippocampus is associated with which form of memory?

episodic

network/systems memory consolidation

episodic memories are initially stored in hippocampus and slowly moved (consolidated) into neocortex

give 3 types of declarative memory

episodic memory (recollecting specific events in time), semantic memory (remember familiar objects/facts), and working memory (a short-term hold)

once consolidated, where are episodic memories stored in the cortex?

episodic memory consists of components light sight, sound, texture, context, stored in different areas of cortex.

reversal potential

equilibrium potential of an ion = the membrane potential at which there is no net flow of that particular ion from one side of the membrane to the other. calculated using nernst equation

what kind of chemical structure is ACh?

ester (not amino acid/derivative like most NTs)

which common recreational drug has many features in common with anaesthetics

ethanol

which drug is usually used in absence seizures

ethosuximide

which nerves can diabetes damage?

everyone goes on about the optic nerve... but diabetes can damage any nerve, leading to dysfunction/neuropathy

how does amyloid beta form?

is cleaved off from amyloid precursor protein (APP) by beta secretase and gamma secretase

name 5 structures of the ascending arousal system

locus coeruleus, laterodorsal tegmental nuclei, pedunculopontine tegmental nuclei, tuberomammillary nucleus, Raphe nuclei

what does LQTS stand for?

long QT syndrome

cingulate gyrus

long curved structure on the medial surface of cerebral hemispheres; the cortical part of the limbic system. wraps around corpus callosum + helps regulate emotion/pain/predicting + avoiding negative consequences

Meibomian gland

long sebaceous gland that lubricates the surface of eye. orifice can become blocked causing styes/chalazia

what is the reverse of long term potentiation

long term depression

corpus callosum lies deep within which fissure of the brain?

longitudinal

myenteric plexus sits deep to which muscles?

longitudinal muscles of the gut wall

metamorphopsia

looking at a straight line, patient sees a wavy line/kink. usually due to a defect in the retina

are commisural fibres between cerebral hemispheres white or grey matter?

white

are the peduncles made from grey or white matter?

white

do acending and descending spinal tracts run in white or grey matter?

white

is the corpus callosum white or grey matter?

white

corticobulbar tract

white matter pathway descending from the primary motor cortex, through the corona radiata of the internal capsule, to contra- and ipsi-lateral cranial nerve nuclei in the brainstem ('bulb' refers to the medulla).

nociceptors

widely branched bare nerve endings which respond to mechanical or inflammatory stimuli, sending pain signals to CNS and mediating the axon reflex

how can you treat korsakoff's amnesic state? how effective is this?

with vitamine B1 (thiamine). reduces confusion/motor symptoms, but amnesia usually persists

if sudanophilic lipids/myelin deposits are seen in a myelin plaque, how recent is the demyelination?

within last few days

in which layer do superficial skin receptors lie?

within the dermis, just below the epidermis

where is the lateral corticospinal tract found in spinal cord?

within the lateral region; lateral to propriospinal tract and medial to rubrospinal tract

are there more men or women in the UK with dementia?

women

which kind of memory is prefrontal cortex associated with?

working memory eg problem solving/delayed response task. (prefrontal neurons shown to fire during time delay between which box flashed with light and picking where food will be)

what are the axes of an audiogram

y axis = hearing level (decibels). x axis = tone frequency (Hz)

are opiods peptides?

yes

can caffeine induce drug dependence