Midterm 2 Study Set

Sympathetic division of the ANS

-aka thoracolumbar division of ANS because preganglionic neurons are located at T1-L2/3 -vasoconstriction of arteries, sweat glands, erector pili mm, dilate pupils, increases HR & BP - Short preganglionic axon(myelinated) -> ganglionic neuron (lateral to spinal cord - close to vertebrae) -> long postganglionic axon(unmyelinated) - design of sympathetic division allows for one signal to trigger a activation of regions far from initial pre-ganglionic neuron - E system: Exercise, emergency, excitement, embarrassment, ejaculation

Hasan Ibn al-Haytham

"Father of Modern Optics"; discovered refractions inversely oriented on the retina,

Short-Term Memory

(When something catches your attention) 7-8 chunks of information activated memory that holds a few items briefly, such as the seven digits of a phone number while dialing, before the information is stored or forgotten

Dorsal(posterior) root ganglion

(afferent) a nodule on a dorsal root that contains cell bodies of afferent spinal nerve neurons - grey matter

Nicotinic receptors

(cholinergic) Always excitatory (skeletal muscle and all ANS ganglia)

muscarine receptors

(cholinergic) Constantly release AcH to muscarinic receptors of heart, may be inhibitory(heart) or excitatory(gut)

ventral(anterior( root ganglion

(efferent) contain motor neurons for somatic NS - grey matter

long-term memory

(encoding) Excitement - RAS is involved (thrilling), rehearsal - repetition, Association - context(like the videos he plays for us in class to draw associations with concepts) Hippocampus interacts with prefrontal cortex in consciously retrieving memories

Diencephalon

(the deeper gray) thalamus, hypothalamus, epithalamus

cholinergic vs. adrenergic receptors

- Cholinergic receptors are parasympathetic - adrenergic (NE/E) sympathetic

Autonomic Nervous System(para and sympathetic)

- Efferent Motor system where effectors are cardiac muscle, smooth muscle, and gland - Somatic(voluntary) Autonomic(visceral: involuntary) - Lateral horn exiting through ventral root(motor) -> entering autonomic ganglion - Hypothalamus largely utilizes ANS to maintain homeostatic control (integrates cortex & limbic system information to the brainstem and SC)

CSF vs Blood Plasma

- More Na+ and Cl- - less CHO, K+ and Ca++ - Does not contain cells or proteins; if not clear, selectively permeable membrane took damage

Transduction in the auditory system

- initially takes place in tympanic membrane of middle ear (acoustic waves -> vibrations) -

Primary Motor Cortex

- the section of the frontal lobe responsible for voluntary movement with action potentials, pre-central sulcus - Motor homunculus - pyramidal cells -> corticospinal tract(output tract)

Gustation transmission pathway

1st order -> extend through facial and glossopharyngeal nerve to medulla oblongata 2nd order -> synapse in brainstem to thalamus(relay center) 3rd order -> tertiary neurons extend from thalamus to insula(gustatory cortex)

dynamic equilibrium

3 axis - turning head around pivot point Semicircular canals and ampullary cupula

Spinal Nerves

31 pairs of nerves arising from the spinal cord 8 cervical 12 thoracic 5 lumbar - conus medullaris (end of spinal cord between L1 and L2) 5 sacral 1 coccygeal

Cerebellum

A large structure of the hindbrain that controls fine motor skills. Primitive motor center: posture, balance, coordination, fine motor control, perfecting center - works with proprioceptors, visual and equilibrium pathways (joints/muscles) informs the cerebellum with static and dynamic movement - Cerebellar Ataxia traumatic brain injury - poor muscular control - match and mismatch, informs frontal lobe how to adjust, sending downstream information right away

temporal lobe

A region of the cerebral cortex responsible for hearing and language. acoustic cortex; separated by lateral fissure

Frontal Lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement

Parasympathic division of the ANS

AKA Craniosacral Plexus: - preganglionic neurons located in brainstem nuclei and S2-S4 segments of spinal cord (SPLANCHNIC): Rest and digest - S2-S4 think "Digest" - CN III, VII, IX, X (7, 9, and 10) all taste related nerves) - SLUD SYSTEM: S- salivation, L - lacrimation, U- urination, d - digestion(defecation) - Longer preganglionic axon(myelinated) -> autonomic ganglion (close to or within effector) -> short postganglionic axon(unmyelinated) - one exception for the parasympathetic system is the oculomotor nerve where the pre-ganglionic neuron is far from the post-ganglionic neuron

Olfactory Transduction

Activated Olfactory receptors initiation a g-protein second messenger system; produces cAMP -> net influx of Na+ and Ca++ -> depolarizes the cell and sends signal to glomeruli(ball of nerves that synapses between mitral and presynaptic olfactory receptors) -> mitral cell(function as relay system) -> uncus (olfactory cortex found in temporal lobe) & limbic system Convergence circuit - takes multiple inputs creating one output

Cranial Nerves and Spinal Nerves are PNS

All cranial nerves are a part of the PNS except CN II(olfactory nerve), bulb functions as it's own relay station, all spinal nerves

Preganglionic axon

All preganglionic axons release ACh onto nicotinic receptors -> post ganglionic axon releases either ACh or norepinephrine -> effector (either muscarinic receptor)

Substantia Nigra

An area of the midbrain that is involved in motor control and contains a large concentration of dopamine-producing neurons Generally a lack of substantia nigra in parkinson's patients

Visual cortex (occipital lobe)

Area of the brain responsible for the initial conscious registration of visual information; the designation of electric (nerve) impulses from the retina

Medulla

Autonomic motor reflex center; vitals center - cardiac, vasomotor, and respiratory; etc functions: vomiting, hicupping, swallowing, coughing, sneezing, and pyramidal decussation(motor tract crossing)

tonotopy

Basilar membrane and cortex are inversely mapped to Hz

sympathetic vs parasympathetic innvervation

Blood vessels: purely sympathetic (no parasympathetic innervation - can dilate and constrict blood vessels with norepinephrine Pupil: sympathetic (dilator pupillae -> more light) and parasympathetic innervation (para = sphincter Pupillae - less light) Lens: Parasympathetic causes near focus (more convex - contracted ciliary) ; sympathetic innervation - none Male genitelia: sympathetic - ejaculation; parasympathetic - erection(need to be relaxed to be aroused) Sweat glands and arrector pili: sympathetic - increases sweat and contraction; parasympathetic has no innervation Saliva: parasympathetic - increases salvation: sympathetic - decrease salvation GI tract: symp - inhibits: para - stimulates Heart: symp - increases heart rate; para - decreases HR

CNs MIDBRAIN (Mesencephalon)

CN III and IV; corpora quadrigemina - superior colliculus important for vestibulo-ocular reflex *balance - inferior colliculus gives spatial audio (sound location); substantia nigra

Cranial Nerves and which area of taste they are responsible for

CN VII -> front 2/3 of tongue, CN IX -> back 1/3 of tongue, CN X -> throat taste

Cerebral nuclei

CNS collection of glial cell (gray matter)

CNs in Pons (metencephalon)

CNs V-VIII; relay impulses from cerebellum to cortex; pneumotaxic center - controls respiration and normal breathing patterns

Long-Term Potentiation (LTP)

Cellular Mechanics behind long-term mem & learning; Encoding includes protein synthesis: - NMDA/AMPA receptors(cells which upgrade new protein receptors and allow for easier potentiation on neurons) upregulated - EPSP threshold is easier to fire - Extended time of potentiation (fires longer)

Olfaction - CN 1 Olfactory Nerve

Chemoreception Only special sense where the receptive cell is the cranial nerve! Olfactory Epithelium: contains olfactory receptor cells, which have specialized cilia extension; cilia trap odor molecules as they pass -> transmitted from the receptors to the olfactory bulb in the brain Basal cells of epithelium replace receptors (NEW NEURONS) Supporting cell - metabolic and physical support; Covid targets these cells, concert doesn't run without security ---> can lead to anosmia(lack of smell)

White Matter in PNS

Collections of axons in form of roots, nerves, and rami

Traumatic SCI(spinal cord injury)

Complete damage = no function below level of injury incomplete = varied function below injury (either sensory, motor or both)

Epithalamus

Contains pineal body. Involved in olfactory senses and sleep/wake cycle; ridge of thalamus; producing melotonin

Broca's area

Controls language expression - an area of the frontal lobe, usually in the left hemisphere, that directs the muscle movements involved in speech. Can still speak but impaired EXPRESSIVE APHASIA

Sensory Homunculus

Demonstrates that the area of the cortex dedicated to the sensations of various body parts is proportional to how sensitive that part of the body is.

epineurium

Dense connective tissue that surrounds entire nerve including fascicles and blood vessels.

Corticospinal Tract (motor)

Descending from cortex to SC; decussates in brainstem , to ventral horn of SC

Receptors

Detect sensory input and send signals to the CNS, all receptors change stimulus into graded potentials Transduce stimuli

Sour H+ and Ca++

Directly enter to inhibit and open two different channels (high pH -> protons); H+ enters and K+ is inhibited -> if k+ stops Ca++ can enter

Target Cells of ANS

Either muscarinic o

limbic system

Encompasses the fornix, mammillary body, hippocampus, amygdaloid body(appropriate response), olfactory tract, olfactory bulb - Learning, emotion/fear, appetites and sex, and endocrine interaction

Pyramidal cells in cerebral cortex

Enter the corticospinal tract(output tract) - large neurons that allow conscious control of precise, skilled, skeletal muscle movements Decussation - right brain -> left body; left brain -> right body - happens in corticospinal tract

Prosencephalon (forebrain)

Forms the Telencephalon (becomes cerebrum) and Diencephalon (third ventricle)

sweet, bitter, umami

G protein coupled receptors sensitive to certain molecules -> increase intracellular Ca++(2nd messenger) -> indirectly depolarize gustatory cells Most sensitive to Quanine(bitter chemical, upregulation of receptors=sensitivty)

Thalamus

Grand relay system(gateway to the brain); memory, emotions, and motor coordination; does not regulate temperature

Cerebral Cortex

Gray matter, every neuron has one axon, 4mm thick

Gustation (taste)

Gustatory papillae - epithelium Circumvallate - division between facial nerve(7) and glossopharyngeal nerve(9) (posterior) Fungiform - contains tastebuds (anterior tongue) filiform - do not contain tastebuds Foliate - contain tastebuds (lateral)

Light Stimulus, dark current stops

Hyperpolarizes the rods as cation channels are closed, voltage gated Ca2+ channels are closed for the rod , allowing for the bipolar cell to transmit glutamate(excitatory) to the ganglion

Coup Injury

Injury directly below the point of impact

countercoup injury

Injury on opposite side of impact

Acoustic (mechanoreception)

Inner ear(labyrinth of negative space) sense mechanical vibration; hearing=cochlear; Equilibrium = vestibule & semicircular canals

Retina

Inverses the visual field through optic nerve II; Photoreceptors dendritic(receptive end) is embedded into a pigmented epithelial cell; melanin is here to minimize the bouncing of light onto dendritic ends Signal genesis and electrical signals travel out o the retina not from retina - glial cells act like fiber optic cables to focus colored light onto cones rods and cones -> bipolar neuron -> ganglion -> collections of these ganglion cells become cranial nerve II

Sensory Association

Language is lateralized to left hemisphere Wernicke's Area is here (speech comprehension) Receptive Aphasia - sensory deficit

Visual Association area

Lemons are yellow

Duration

Longer duration -> lower Hz of APs; this is due to habituation of stimuli: receptors will stop producing neurons, stimulus has to change

Parkinson's disease

Low dopamine - generally a IPSP generator Glutamate: EPSP generator Loose the inhibitory effect of dopamine, glutamate continues to excite the neuron which meant to inhibit without any competition IPSP > EPSP in corticospinal tract; you cannot inhibit the inhibitory output of a neuron Symptoms: -paucity of motion: difficulty creating appropriate movements -resting tremors; imbalance of outputs to the brain from agonist and antagonist group -shuffling gait -stooped posture with loss of balance, freezing gait

Types of Sounds and Sensation

Lower Frequency = lower pitch (slower rate of vibration) towards apex of cochlea aka helicotrema (tonotopic organization) Higher Frequency = higher pitch (faster vibration) closer to base of cochlea (tonotopic organization) Higher amplitude = louder lower amplitude = quieter (less dramatic) Volume = wave amplitude Pitch = frequency Timbre = resonance quality (harmonic content) - characteristics of different voices

Receptor Modality

Mechanoreceptors - hair, free nerve endings, touch Chemoreceptors - gustation, smell Nocioreceptors (pain) - free nerve endings Electromagnetic receptors (photoreceptors) - sense light, vision Thermoreceptors - extreme touch and temperature

Efferent

Motor output to "effectors" which respond to environmental stimuli (muscles & glands)

REM sleep

Movement inhibited everywhere except eye muscles, Heart rate is elevated, Brain EEG is similar to that of the awake state

NREM Stages 1-4

Much deeper, restful type of sleep. Stage 1-lasts 5-10 minutes, eye movement slows. Stage 2-still fairly light sleep-brain produces sleep spindles, lasts about 20 minutes. Stage 3-beginning of deep sleep. Stages 3 & 4- Deeper sleep, growth hormones reach their peak, repairs muscles and tissues, boosts immune function, builds up energy for next day.

Brachial Plexus (5 major nerves supply entire upper limb) (C5-T1)

Musculocutaneous Nerve, Ulnar Nerve, Median Nerve; work together to form the M shape

Neurulation (3rd week)

Nervous tissue forms from thickened ectoderm (neural plate) creates a crest neural groove which will develop into the neural tube in week 4 of development - neural plate becomes the neural tube; the neural tube expands into the brain vessicles

Cholinergic Receptors

Nicotinic and Muscarinic bind AcH

Fibrous CT (Eye Anatomy)

No direct blood supply; aqueous humor indirectly nourishes the fibrous tunic: Sclera attaches to the rectus and oblique muscles; Cornea: transparent transparent CT which houses the aqueous humor

Why do we sleep? (TED) (GLYMPHATIC SYSTEM)

No lymphatic vessels in brain(no waste clearance system as performed in rest of body); CSF is pumped through the brain along the outside blood vessels which only happens while sleeping

Otolithic membrane and maculae

Otolithic membrane interacts with the hair cell; creates chronic depolarization by otoliths within the membrane constantly pressing down, so that when rate of movement changes there is a sensation hence why you only sense acceleration and deceleration

Ear Anatomy

Outer: external acoustic meatus -> tympanic membrane Middle (Air filled space): tympanic membrane -> oval window (ossicles vibrate and amplify 20x) -Stapes attaches to oval window inner (fluid - perilymph; high NA+ and Low k+): fluid filled labyrinth carries vibrations to receptors located here - round membrane - allows for movement of perilymph

Sphincter Pupillae

Parasympathetic control of pupil; causes the pupil diameter to shrink when there is no longer a need to have as much light enter the eye (lateral horn - autonomic)

Lens accommadation

Parasympathetic system - attached from CN III to ciliary body; contracts ciliary body creating a convex shape to the lens allowing for focus of near by objects

NMDA-Dependent Sensitization

Prevailing theory for chronic and recurring pain

Neural tube -> brain vesicles (Neurulation)

Prosencephalon Mesencephalon Rhombencephalon

arachnoid villi (granulations)

Protrudes through the dura mater to allow CSF to drain back into the venous circulation(empties into jugular vein)

Pruning

Pruning of long term memories occurs when there is too much upregulation and no longer need receptors binding to ligands, reduction is receptors after upregulation

Cortical Blindness

Receptor(retina) is normal but damage to visual cortex has occured; due to PCA(posterior cerebral artery) stroke

Perception

Receptors detect sensory input send signal to CNS -> Circuits connect sensory receptor to the CNS for perception -> perception is the interpretation of the signals from those receptors

Phototransduction (bleaching)

Rhodopsin gets "bleached" on the dendritic end of the photoreceptors, light makes it so rhodopsin is no longer a bent hydrocarbon chain by interacting with double bond -> kicks off second messenger system -> byproduct enter pigmented layer to be recycled (vitamin A important for recycling process): trans-retinal -> cis-retinal -> opsin -> rhodopsin

Rods vs. Cones

Rods: Primarily responsible for noncolor vision, high sensitivity to light (can function in dim light), many rods converge onto one ganglion, and 20x more numerous than cones Cones: Primarily sensitive to color(think "C"ones = "C"olor), one cone synapses onto one ganglion allowing for a more clear image as opposed to rods. Red Green and Blue receptive cones (RGB)

Spinothalamic tract(sensory)

SC -> Thalamus: decussates in SC to opposite cerebral hemisphere: Tertiary neurons = internal capsule; create sensory homunculus

More Inner Ear Anatomy (transduction)

Scala Vestibuli - ascends to apex of cochlea Scala Tympani - descending portion of cochlea Cochlear Duct - between Scala vestibuli and tympani; filled with endolymph and contains the organ of corti Organ of Corti - Filled with hair cells(stereocilia); closely covered by tectorial membrane(doesn't move) -> basilar membrane moves and pushes hair cells up and bending -> mechanically opening potassium mechanically gated channels and allowing for depolarization of the cell

General Sensation

Somatic(touch, pain, pressure, and temperature) and Visceral(pressure and pain

primary sensory cortex

Somatosensory cortex, feelings of touch, pain, proprioception(idea of where you are in space), temperature would be experienced by "you" here

Special Sensation

Specific stimuli: vision, hearing, taste, smell, equilibrium

Sensation

Stimulus -> receptor -> nerve transmit info (afferent) -> brain interprets(conscious awareness) -> conscious awareness of a stimulus

Intensity

Stronger Stimulus -> higher Hz of APs Certain number of APs based on intensity, the brain communicates in frequency (Hz)

cerebral spinal fluid(CSF)

Sub-arachnoid space between meninges is filled with this fluid that cushions and protects the CNS Space of Neural tube -> turns into ventricles -> filled with CSF Function: Buoyancy(suspend brain & spinal cord in fluid), Protection(ECF stability - waste removal, hydraulic shock absorber, stable environemnt)

2nd order(Perception)

Synapses with 1st order in CNS; decussation in SC or medulla and ascends to the synaptic cleft of the thalamus

1st order(perception)

The afferent signal on the PNS nerve

Photopsin

The visual pigment for cones, the populations isoforms are based on light nm, RGB, heavily concentrated in fovea centralis

Primary Acoustic Cortex

Tonotopic mapping - senses which Hz(frequency) of sound is being heard

White Matter

Tracts(internal Capsule) - Brain and Spinal Cord to communicate with each other Commissures (in corpus callosum) - connect gray matter of the two hemispheres; Association Tract - communication between left and right hemispheres

Beta Receptors

Usually inhibitory (With exceptions: pacemaking cells of your heart - bind norepinephrine to speed up heart rate) Beta-blocking medication take a drug with a higher affinity than norepinephrine to prevent varied conditions (heart failure/chest pain/heart attacks)

Auditory Pathway

Vestibulocochlear nerve -> medulla -> midbrain -> thalamus -> primary auditory cortex(temp. lobe)

Fascicle

a bundle of nerve or muscle fibers bound together by connective tissue

Benign Paroxysmal Positional Vertigo (BPPV)

a common cause of vertigo that occurs when there is a shift in the location of small crystals in the semicircular canals Epley Maneuver: move displaced otoconia from maculae back into the semicircular canal, otoliths which take a joy ride in the semicircular canal would bump into the cupula

dermatome map

a diagram of the cutaneous regions innervated by each spinal nerve

Blood-Brain Barrier (BBB)

a selective mechanism that protects the brain from toxins and infections; Junction of astrocytes Function: - defends osmolality - Waste products - Pathogens - Toxic Substances like drugs - Wilf fluctuationsterm-148 What crosses: CHO, Amino acids, some ions via transport channels. LIPID SOLUBLE PRODUCTS CAN CROSS: FFA , O2, CO2, EtOH

Hydrocephalus

abnormal accumulation of fluid (CSF) in the brain Cause: abnormal CSF flow and resorption Signs: rapid head circumference increase, "Sun-setting" downward gaze of the eye, Vomiting, irritability, seizures Case study Qs: Enlarged lateral ventricles - lack of septum pellucidum, CSF not flowing out lateral ventricles, sutures are inflexible in adults

Alpha Receptors

adrenergic receptors that are usually stimulatory

"General Sense"

any sensory system that is distributed throughout the body and incorporated into organs of multiple other systems, such as the walls of the digestive organs or the skin; carried out by dorsal root ganglion - signals when threshold is met through spinothalamic tract - decussation applies here too

fovea centralis

area consisting of a small depression in the retina containing cones(no rods) and where vision is most acute

gustatory cortex

area of the brain that receives and interprets tastes from the tongue; part of insula which is a section of the parietal and temporal lobe - Think emotional eater; think limbic system

Reticular Activating System (RAS)

brain area that plays a key role in arousal; Spinothalamic interaction which carries out through the cortex; brain stem integrates, serotonin & norepinephrine released resulting in -elevated heart rate, breathing rate, and kidney activation

motor homunculus

broad areas of primary motor cortex devoted to controlling movements of different body reterm-37gions

Vestibule mechanoreceptions

causes influx of Ca++ triggering depolarization of hair cells Transduction occurs in vestibule and semicircular canals

Gray Matter

cerebral cortex Cerebral nuclei

vascular tunic

choroid, ciliary body, iris(2 diff muscles)

Perineurium

coarse connective tissue that bundles fibers into fascicles

Myopia (nearsightedness)

condition in which close objects appear clearly, but far ones do not; concave lens of glasses would help treat

Intraventricular foramen

connects lateral ventricles to third ventricle

Cerebral aqueduct

connects the third and fourth ventricles

Superficial cerebrum

cortex (grey matter), lobes are distinguished with the central sulcus, parietal occipital sulcus and the longitudinal fissure

Endoneurium

delicate connective tissue around individual nerve fibers in nerve

Dura Mater

dense irregular connective tissue (Durable matter)

Ectoderm

develops into nerve tissue and skin; forms an exoskeleton

neural plate

flat group of cells present in prenatal development that becomes the brain and spinal cord

Ventral Rami

form a complex of networks (plexus) for the anterior (MOTOR & SENSORY); bigger than dorsal because it goes everywhere

Gray matter in the PNS

ganglia (collections of neuron cell bodies in PNS)

ampullary cupula

gelatinous material that hair cell cilia are embedded in; lag in movement of endolymph and cupula

Dural venus sinus

group of sinuses or blood channels that drains venous blood circulating from the cranial cavity (basically an arachnoid granulation)

Receptive field

important for discrimination, the greater the receptive field of one dendrite/neuron the less proficient it is at distinguishing stimuli

Afferent

input entering CNS and delivered by the PNS, afferent can also be CNS to CNS

somatosensory association area

integration and interpretation of somatic sensations; comparison of past to present sensations; Afferent area of your brain, any homeostatic mechanism comes here, processes sense of touch, pain, proprioception; things like "did i like that touch"

Basal Nuclei

internal islands of gray matter in CNS

Taste physiology of salt (Na+ and K+) transduction

metal ions dissolve in saliva -> cation enters taste pore -> directly enters cell

Rhombencephalon (hindbrain)

metencephalon -> pons & cerebellum and myelencephalon -> medulla oblongata

Mesoderm

middle germ layer; develops into muscles, and much of the circulatory, reproductive, and excretory systems

Static equilibrium

moving side to side and up & down: vestibule Comprised of Utricle and Saccule Utricle - Horizontal acceleration Saccule - Vertical Acceleration When looking down -> reduced action potential (otoliths don't compress hair cell as much)

Myotomes

muscle or groups of muscles innervated by a specific motor nerve

Nerve Plexus

network of interweaving anterior rami of spinal nerves

Dilator Pupillae

opens the pupil under sympathetic stimulation; if you need more light it will dilate (lateral horn - autonomic)

Hypothalamus

part of diencephalon, function to: -Grand puba of homeostasis -thirst center -appetite and weight control -physical responses to emotions -blood pressure and heart rate -sleep cycles

Neural Crest

pinches off - develops sensory(dorsal root) ganglia of PNS (ENTIRE PNS)

pre-motor cortex

plans and coordinates skeletal muscle movement; association cortex - uses tracts collterm-35ections of axons (corona radiata)

Circuit Level

processing at this level is involved with delivery of impulses to the appropriate region of the cerebral cortex for stimulus localization and perception

Choroid Plexus

produces CSF; selective membrane; braiding of the choroid plexus takes up space of the ventricles Ependymal Cells - glial cells Endothelial Cells - capillaries

Parietal Lobe

receives sensory input for touch, taste and body position, post central gyrus - Primary sensory cortex Contains somatosensory association area

Multimodal Association

receiving inputs from multiple sensory modalities; integrates information and formulates composite higher experience: Imagination, judgement, decision making, long term planning

Amnesia

retrograde can't recall memories; anterograde - can't form new memories

Lacrimal Gland

secretes tears; controlled by cranial nerve 7 (VII)

Maculae

sensory receptors for static equilibrium

dark current (rods)

sodium and calcium channels open in the absence of light -> depolarizing the cell -> causes rods to constantly release glutamate(normally excitatory in CNS but inhibitory here) -> inhibits If the bipolar cell receives glutamate it hyperpolarizes the bipolar cells and inhibits

Acoustic association area

stereo and localization

3rd order(perception)

thalamic projection neuron sends signal to primary somatosensory cortex(in parietal lobe)

Dorsal Ramus

the division of posterior spinal nerves that transmit motor impulses to the posterior trunk muscles and relay sensory impulses from the skin of the back; dorsal is smaller because it relates to only the back (MOTOR & SENSORY)

sensory memory

the immediate, very brief recording of sensory information in the memory system

Endoderm

the inner germ layer that develops into the lining of the digestive and respiratory systems

Mesencephalon (midbrain)

the midbrain; a region of the brain that surrounds the cerebral aqueduct; includes the tectum and the tegmentum

Primary Visual Cortex

the region of the posterior occipital lobe whose primary input is from the visual system

gate-control theory

the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain Interneurons generally inhibitory ; gate=nociceptor inhibits the interneuron, so pain continues to the cortex

nervous tunic (retina)

the starting point of the visual pathway containing photoreceptors(not neurons)

Transducing stimuli

turn into graded potentials and release neurotransmitters onto neurons -> conduct APs Code for type of stimuli, location, intensity and duration

Olfactory cortex

up to 2nd order nerves

orbital cortex

use of rewards to guide behavior; inhibits undesirable behavior

uncus

ventral surface of temporal lobe; part of limbic system; used for smell part of olfactory cortex

shingles (herpes zoster)

viral infection producing the eruption of highly painful vesicles that may follow a nerve path; causes pain in dermatome affected

Referred pain

visceral pain may feel as if it is coming from some part of the body other than the part being stimulated (soma pain) i.e: heart attack