NRS 301 Exam 1, Exam 2, Exam 3, EXAM 4 combined
Nerve agents such as *Sarin, VX, Novichok,* chemically modifies ___________ __________ on AChE. Thus the __________ is no longer cleaved and muscles no longer controllable.
ACh-binding site; ACh
Ach in AD
AD leads to death of cholinergic neurons in brain treatment: AchE inhibitors - boost existing Ach levels by preventing degradation -improve symptoms declines with damage
glutamate receptors
AMPA and NMDA - glutamate bind AMPA to inc NA conductance - Mg block displaced once postsynaptic membrane depolarized - Ca enters thru NMDA
The _______ ______ is a subtype of glutamate receptor; a glutamate-gated ion channel that is permeable to Na+ and K+. It has __________ (tetramer), and the extracellular domain has a "clamshell" that binds glutamate. The receptor binds _______ glutamates to open.
AMPA receptor; 4 subunits; two
ACh cleaved by ___________.
Acetylcholinesterase (AChE)
Opsin are
Activated by different wavelengths of light
Advanced therapeutics for PD
Add genes that induce pluripotency (stem cell phenotype) Factors and genes to push them to DA neurons Skip iPSC step and directly make neurons then look for markers of DA phenotype
The selectivity in KcsA is essentially K+ ions in solution surrounded by water. The K+ ions must shed ________ to pass through channel. After passing through the filter, K+ re-associates with ________.
H2O
degree of Ca influx determine LTP v. LTD
HFS-> LTP LFS->LTD
How can you test the role of an ion?
Change [X]out and measure changes in membrane potential
The loss-of-function mutation in sodium channels causes _____________.
Chronic Indifference to Pain
GABA and glycine receptors are similar to AChRs. The conduct ______; and they _________ likelihood of firing a spike
Cl-; reduce
peptide neurotransmitters
Enkephalins (opiods)
_________-_________ are an example of rapidly adapting fibers that fire in bursts at the beginning & end of stimulation. These are sensitive to the ___________ in stimulus. ~Think *vibration* (time-varying pressure changes)
Pacinian corpuscles, changes
The delayed rectifier channels of the action potential open later than voltage-gated sodium channels because delayed rectifiers:
Have intrinsically slower kinetics
Endogenous
Produced within the body
Opsin
Proteins that are light sensitive Allow for targeted expression, so effect can be restricted to a defined set of cells
_________-_________ is the adding together of EPSPs generated simultaneously at many different synapses on a dendrite.
Spatial summation
selectivity filter
The narrowest part of a ion channel; it determines the rate of ion passage across a membrane
What happens to a neuron if the external concentration of potassium increases?
The neuron depolarizes
Visceral PNS
The part of the peripheral nervous system that innervates the internal organs, blood vessels, and glands; also called autonomic nervous system.
Somatic PNS
The part of the peripheral nervous system that innervates the skin, joints, and skeletal muscles.
___________ are composed of all the following features: a) Active zone in the presynaptic cell b) Cleft between the cells c) Neurotransmitter in vesicles
Synapses
__________ channels are activated by menthol, and it's generally activated by non-painful temperature decreases. It tends to produce the feeling of cold.
TRPM8 (channels)
________ channels are activated by capsaicin, and is activated by noxious temperature increases. It tends to produce the feeling of heat.
TRPV1 (channels)
Tau hypothesis of AD
Tau protein abnormalities (hyperphosphorylation) initiate the disease cascade. AD tau is found throughout neuron, dendrites, and soma when it shouldn't be there associated with paired helix filaments in degenerating neurons
__________-__________ is the adding together of EPSPs generated at the same synapse if they occur in rapid succession, within about 1-15 msec of one another
Temporal summation
somatic sensation
The senses of touch, temperature, body position, and pain.
True or False: Once a concentration gradient is established, the electrical gradient requires the movement of few ions
True
Transorbital lobotomy
Type of frontal lobotomy Results: decreased anxiety, blunting of emotional responses, loss of emotional components of thoughts, inappropriate behaviors, lower moral standards, trouble concentrating But no loss of memory or IQ Ended in US
Oligodendrocytes
Type of glial cell in the CNS that wrap axons in a myelin sheath.
Schwann cells
Type of glial cell in the PNS that myelinates axons
The 4 different types of gating in ion channels are...
Voltage (depolarized, hyperpolarized); Ligand (Ca2+); Inactivation; Open all the time
Probe cause v. effect
What optogenetics allows us to do Prior studies allowed observation of firing patterns with behavior/phenomena but didn't know if that firing "caused" behavior
Provides electrical insulation
Glia
_________ convert glutamate to glutamine (secrete glutamine, which is taken up by neurons)
Glia
When glutamate is cleared from the cleft by transporter proteins on glia and neurons; it is called __________ _________.
Glutamate recycling
__________ is dominant in spinal cord and lower brainstem
Glycine
______________ describes membrane potential becomes more negative
Hyperpolarization
The _____-_______ calcium channel is responsible for the release of Ca2+ from the __________- ___________ which is very important in ___________-___________.
IP3 receptor; endoplasmic reticulum; intracellular signalling
Ionic concentration differ between the inside and outside of a cell because of...
Ion transporters
GABAA and glycine receptor are ___________ _________
Ionotropic receptors
Inactivation particle (Na channel)
Loop between domains III and IV
learning
acquisition of new knowledge or skills
bottom-up processing
analysis that begins with the sensory receptors and works up to the brain's integration of sensory information
Some of the first recordings of nerve potentials were made by:
Lord Adrian
This person made some of the first recordings from individual neurons
Lord Adrian
Cable theory was established by...
Lord Kelvin
The advantages of signaling with ____________-__________ include: - Very few ions move to establish resting membrane potential (<0.02%), so total ionic concentrations change little - Efficient form of signalling - Cell can change potential simply by changing permeability
Membrane potential
Learned fear
Memories associated with fear forms quickly and are long lasting Much harder to forget fear memories than positive memories
Mesocorticolimbic DA
Meso= mid, VTA Midbrqain contains DA neurons DA projections from ventral tegmental area (VTA), nucleus accumbens, prefrontal cortex
GABAb is a ____ receptor.
Metabotropic
NMDA receptor has a structure that is very similar to AMPA receptors. At rest, a ______ ion blocks its pore; which is usually dislodged by _____________. It is permeable to K+, Na+, and Ca2+.
Mg2+; depolarization
____________ in the axons provide for transport to and from synapse
Microtubules
radial glial cell- proliferation
(early)symmetrical cell division result in more radial glial cells (later) asymmetrical cell division 2 fates: keep dividing in ventricular zone + migrate to cortex and never divide again
synaptic competition
- if both input from both eyes are equal: activity at neuron is equal, inputs from both eyes are maintained - if balance is disrupted: input from one eye is decreased
Neocortex
6 complex layers. only found in mammals
____________ in the axons provide for structural stability
Neurofilaments
Efferent
carry info away
afferent
carry info into
memory
retention of learned information declarative and non-declarative
amnesia
serious loss of memory and/or ability to learn
raphe nuclei contain most of the:
serotonergic neurons of the brain
Abeta afferents
carry tactile information about touch, pressure, stretch and vibration
human fetal ventral mesencephalon (VM) tissue grafts
cell based therapy to restore DA in PD
gray matter
cell bodies of neurons
Glial Cells
cells in the nervous system that support, nourish, and protect neurons. NOT excitable
migration
cells move throughout body to take up positions that influence their function
telencephalon differentiates into (2)
cerebral cortex basal telencephalon-> basal ganglia
Thermoreceptors are able to adapt, and detect:
changes in temperature
Choline taken up by presynaptic cell; choline is reassembled into ACh by _________ _____________. And ACh loaded into vesicles.
choline acetyltransferase (ChAT)
dopamine
common final pathways of drugs of abuse circuits controlling "wanting" go into overdrive
neurofibrillary tangles
composed of: paired helical filaments (modified cytoskeleton elements, tau, tubulin) b-amyloid
Axons are responsible for...
conducting impulses away from cell body (soma)
Corpus Callosum
connects the hemispheres of the cortex
Internal Capsule
connects the thalamus to the cortex
Dopaminergic Nuclei of Midbrain
consists of 2 parts; substantia nigra (movement initiation) and the ventral tegmental area (emotion/reward)
brainstem
consists of the medulla and pons. sensory info and motor function. autonomic regulation
Diencephalon
contains the thalamus and hypothalamus. responsible for primitive behavior (feeding, drinking, sex) and endocrine activity (pituitary)
ocular dominance histograms (cat)
contralateral eye= group 1, activated by either eye ipsilateral eye= group 5, activated by either eye groups 2-4 activated by both eye
Amygdala
controls emotions and fear. receives sensory input from the thalamus.
Olfactory Complex
controls smell and is directly connected to the olfactory bulb via the olfactory nerve. 4 layers
Basal Ganglia
controls voluntary movement and motor behavior, reward/emotion
___________ describes the process during the action potential when sodium is rushing into the cell causing the interior to become more positive.
depolarization
_____________ refers to the area of the skin that is innervated by the dorsal roots of a single spinal cord segment.
dermatome
___________ are the segmental organization of spinal nerves. There are 30 segments are are divided into 4 group. These consist of ________ (dorsal roots) & _________ (ventral roots) nerves that carry information from different parts of the body which enter/exit the spinal cord at different segments.
dermatomes, sensory, motor
Primary somatosensory afferents vary widely in the ___________ and __________ level.
diameter, myelination (level)
asymmetrical division
different proteins to two daughters different fates
Similar depolarization yields ___________ __________ patterns in neuron activity graphs.
different spiking (patterns)
chemorepellants
diffusible molecule that chases axons away ex. slit- Robo (slit receptor)
chemoattractants
diffusible molecules that attract growth cones toward their targets ex. netrin- attract axons of dorsal horn neurons to midline
How does passive synaptic transmission occur?
diffusion (mainly for neuropeptides)
sensory adaptation is the __________ sensitivity as a consequence of constant stimulation.
diminished (sensitivity)
Mechanotransduction is the conversion of mechanical stimulus to an __________ or _________ signal. Different channels tend to respond to different forces.
electrical (or) chemical signal
What is an action potential?
electrical impulse that travels down the axon triggering the release of neurotransmitters
Wilder Penfield's research on the brain included brain mapping using ___________-__________ of S1 on awake neurosurgical patients. He recorded action potentials while touching different areas of the body testing receptive fields.
electrical stimulation
progressive ratio
each subsequent reward requires more presses, 1 press to obtain the 1st reward, but 32 presses needed for 10th reward amount of work to obtain a reward, motivation
neurite
early axonal and dendritic processes
embyronic stem cell (ESC)
early blastocyst from surplus human embyros reprogrammed into DA progenitor cells "foreign"
deep brain stimulation (DBS)
electrodes inserted into brain areas (GP, STN) widens window, allow meds to be effective longer and with less SE
blastula
embryo is a hollow ball of cells - the flat disk
The periaqueductal gray (PAG) receives input from brain areas involved in __________. An example of an area would be the amygdala.
emotion
action potential propagation is essentially the _________ and ________ of Na+ and K+ channels. Membrane potential is pushed to depolarize, and reach positive values to then repolarize, dropping to the final state of being more hyper-polarized than it was at rest.
opening & closing (of Na+ and K+ channels)
symmetrical division
equal partition of cell contents two of same cells
The gain-of-function mutation in sodium channels causes ______________ and _____________. NaV1.7 activates at more _____________ voltages.
erythromelalgia; paroxysmal extreme pain disorder; hyperpolarized
iPSC restoration of DA in PD
extraction of any cell expansion in vitro differentiation into progenitor neurons immature DA neurons
Chemical Nociceptors respond to
extreme pH levels, environmental irritants, endogenous chemical signals
Thermal nociceptors respond to
extreme temperatures
Abducens Nerve
eye movement
Oculomotor nerve
eye movement
Trochlear nerve
eye movement
strabismus
eyes are not aligned (cross-eyed) can result in permanent loss of stereoscopic vision
Trigeminal Nerver
facial sensation
wanting circuits are
fairly diffused
liking circuits are
fairly distinct
fixed ratio
reward deliver after a set number of responses (consummatory processes)
extracellular matrix
fibrous proteins deposited between cells that serve as a substrate; contains protein that attracts/repel
In sensory adaptation, stimulus intensity in encoded by the _______-_______ of the receptor.
firing rate
In sodium channels, there are ______ domains, where each domain similar to K channel monomer. There are _____ transmembrane domains, S____ in particular has multiple _________ residues that act as voltage sensors. And there is a _________-_______ between S5 and S6
four; six; (S)4; positive; pore loop
How does information flow?
from the periphery to the cortex
Anterior
front of the body
behavioral changes that occur as person transitions to addiction are
function of progressive neuroadaptations in the brain= synaptic changes, plasticity, learning
Group of somata (PNS)
ganglion
group of somata
ganglion
APP
gene related to type 1 early onset familial mutation increase B-secretase cleavage-> familial
PS-1
gene related to type 2 early-onset familial I
PS-2
gene related to type 3 early-onset familial
ApoE4
gene related to type 4 late-onset familian and sporadic
ectoderm
give rise of nervous system and skin
neural progenitors
give rise to all of neurons and glia are multipotent stem cells
mesoderm
give rise to bones and muscles
endoderm
give rise to lining of internal organs (viscera)
vestibulocochlear nerve
hearing and balance
HFS
high freq stim cause by large inc in Ca activates kineases= LTP
Neurons have _______ [K+] in and _______ [Na+]in
high; low
Feedback of the nervous system consists of _______-_______ areas projecting back to the earlier parts of the pathway. This is also referred to as top-down processing.
higher order (areas)
posterior parietal cortex
highest order of somatosensory cortex. reintegrates the parallel pathways (somatic, visual, movement, planning and attention)
The calcium-activated potassium channels are _________-________ neurons can build up Ca2+ inside. The activation of K+ channels reduces ___________.
highly-active; spiking
hippocampus
hippo=horse - 1st indication that hippo involved in long term memory
Mast cells release
histamine
adaptation rate describes:
how quickly a receptor ceases to fire with ongoing input
Bienenstock Cooper Monroe Plasticity
if fire together then wire together, then all synpases will be saturated which decreases max computation power. if out of sync, lose your link (prevent saturation of synpases)
conditioned stimulus (CS)
in classical conditioning, an originally irrelevant stimulus that, after association with an unconditioned stimulus (US), comes to trigger a conditioned response.
where is myelination found in the neuron?
in the axons
where are the spines found in the neuron?
in the dendrites
where in the nucleus found in the neuron?
in the soma
Asterognosia
inability to recognize common objects by touch due to damage in the Posterior parietal cortex
Neglect syndrome
inability to recognize parts of your body as your own due to damage in the posterior parietal cortex
striatum: indirect pathway
include subthalamic nucleus inhibits direct pathway for competing motor acts striatium->GP->subthalamic nuc-> stim GP
Prostaglandins ________ sensitivity of nociceptors, and are inhibited by drugs such as aspirin/NSAIDS.
increase (sensitivity)
all addictive substances ______
increase mesoaccumbal DA release
Stimulation experiments measure __________-__________ input. An example of this would be to train a primate to selectively use two digits (D2 & D3); so the resulting effect would be that the area of the cortex responding to D2 & D3 increases in size *at the expense* of D1 and D4.
increased sensory input
rat pursuing/ approaching
indicates positive experience
relapse
induced by stress, cues, drug use
The T-type ("transient") calcium channels is responsible for the __________ of the likelihood of spiking. This channel is activated by ________-_________.
influence; small depolarizations
top-down processing
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations
familial
inherited with a clear genetic basis gave insight into pathophysiology of AD
GABA and glycine are major _________ neurotransmitters
inhibitory
Vagus nerve
innervates digestive organs, heart and other areas. visceral and autonomic
cortex forms
inside-out upper layers built on top of lower layers
_____-_______ is a property of ion channels that are selectively permeable to some ions and not to others
ion selectivity
acetylcholine is an ___________ receptor, which are also known as nicotinic acetylcholine receptor.
ionotropic
Ligand-gated receptors are called ___________ receptors. They tend to be _________ ________ channels, and influence _________ ________ of postsynaptic cell.
ionotropic; open intrinsic (channels); electrical state
In the primary afferents of the pain pathway that ascend contralaterally, the dorsal column ascends __________, and decussates later.
ipsilaterally
spina bifida severity ____
is proportional to levels of fluid meninges and spinal cord protrusion
trophic factors
life-sustaining substances that are limited in quantity; NGF, BDNF switches off apoptotic genes and promotes neuronal survival
internal capsule
links cortex to brain stem
types of declarative memory
long term short term working memory
Parkinson's disease (PD)
long term neurodegenerative disorder that affects primarily the motor system some early onset forms happen before 60 causes: familial and sporadic forms drug of abuse: MPTP
A-delta fibers have a _______ diameter, are myelinated, and is the ________ pain experienced. It tends to be fast, sharp and intense.
medium, first
AD risk factor of ApoE
risk factor not a genetic link ApoE4 conveys the highest risk apoE 2/2<apoE 2/3<apoE 3/3<apoE 3/4<apoE4/4
infants have more/less synapses than adults
more
K+ channels endow neurons with diversity of properties. They can be _________ or ________ easy to trigger _________ _________. They can also fire _________ ________ at different rates.
more or less; action potentials; action potentials
The delayed rectifier activates __________ ________. It stays open for a ________ duration, and it may flicker closed.
more slowly; longer
Highly-permeable ions have _________ influence on resting potential.
most (influence on resting potential)
anencephaly
most common NTD screen alpha-fetoprotein levels (leaks from CNS into mother's blood) roof of cranium missing-> undeveloped brain not compatible with life
tolerance
most drug needed to get same effect
viruses
most effective delivery vehicles for gene therapy
The L-type calcium channels are responsible for ___________-__________; and synaptic transmission in some sensory cells.
muscle contraction
acetylcholine are released by neurons that activate _________; also known as ______________. This neurotransmitter is a part of the CNS, important in attention and memory.
muscles; motorneurons;
________-________ covers the axon of some neurons and helps speed neural impulses
myelin sheath
multiple sclerosis
myelin sheath destruction. disruptions in nerve impulse conduction. symptoms: muscle spasms/weakness, lack of coordination, loss of autonomic motor function
The Nodes of Ranvier are the gaps in the __________-__________ of a nerve, between adjacent ___________ cells. It's also the location where voltage-gated sodium channels are confined.
myelin sheath, Schwann (cells)
In terms of myelination, the larger the diameter is indicates more ________, and thus ________ transmission.
myelin, faster (transmission)
In terms of myelination, the smaller the diameter is indicates less ________, and thus ________ transmission.
myelin, slower (transmission)
A-delta fibers are (myelinated/nonmyelinated).
myelinated
white matter
myelinated axons
white matter are the:
myelinated axons
the propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials is referred to:
saltatory conduction
Reticular theory holds that:
nervous system is a continuous network of cells
PNS arise from
neural crest cells
steps of neurulation
neural groove -> neural fold (walls of groove)-> fuse dorsally to form neural tube -> give rise to entire CNS
brain (retina/eyes) arises from
neural tube
The following are the ways _________ are specialized. a) The branching patterns of their dendrites b) The branching patterns of their axons c) The types of ion channels they express
neuron (specialization)
proliferation
neuronal and glial precursors are born during development
The neuron doctrine holds that:
neurons are discrete cells
lateral inhibition
neurons that are stimulated inhibit nearby neurons to help discriminate areas where the stimulation is coming from
Hebb's postulate
neurons that fire together wire together
Hebbian Modification
neurons that fire together wire together
synaptic vesicles are the membrane-bounded compartments in which synthesized __________________ are kept.
neurotransmitters
Sir Bernard Katz Experiment
neurotransmitters are packaged in quanta (vesicles)
The chemical signals convey information between neurons are __________ and the __________ and _________ systems
neurotransmitters; synthesis; reuptake
___________ ____________ receptor are made up of 5 subunits (pentamer), has a large ___________ ligand-binding domain. It tends to bind to two ACh molecules to open, and causes ____________ change in channel pore. The bottom of channel pore contains __________-charged amino acids; it permits K+, Na+, Ca2+ to permeate. "Non-selective cation channel"
nicotinic acetylcholine; extracellular; conformational; negatively
striatum: direct pathway
no activity in striatum: - GP neurons fire spontaneously - inhibit motor thalamus - suppresses motor act activity in striatum: - inhibits GP - disinhibits motor thalamus - motor act striatum-> (-) GP-> (-) VL thalamus-> (+) movement
sporadic
no clear-cut genetic basis causes are from a combination of genetic, environmental, and infectious diseases
unconditioned stimulus (US)
no training needed to produce response
Melzack and Wall's Gate Theory explains that the __________ signals are gated by the inhibitory interneurons in the spinal cord.
nociceptive (signals)
ipsilateral
same side
wanting
satisfying a craving
The trigeminal touch pathway synapses on the _______ neurons in the *ipsilateral* trigeminal nucleus of the ______.
secondary (neurons), pons
reelin
secreted by neural precursor cells in marginal zone that tells migrating cells to stop
PD pathogensis
selective loss of pigmental neuron (DA) in midbrain substantia nigra
Meissner corpuscle
sense fluttering and texture (medium fast)
Merkel receptors
sense pressure (slow)
Ruffini cylinder
sense stretching from joint movement (fast)
Pacinian corpuscles
sense vibrations (very fast)
memory acquisition
sensory experience-> short term memory experience is encoded by synaptic modification
Homunculus represents the density of ________-________ to S1 from each body region.
sensory input
Where does chickenpox lay dormant?
sensory nerves
The _______-________ amongst the K+ channels are activated by _____________. They ____________ with prolonged depolarization. The neuron becomes easier to excite during this channel's activity. And different types have different _________ & _________ of inactivation
shaker channels; depolarization; inactivate; kinetics; extents
Mechanical Nociceptors respond to
sharp objects or intense pressure
critical period for plasticity of binocular connections
shifts can occur early but if deprivation occurs late, there is no shift: time limit on shift
memory consolidation
short term memory-> long term memory temporary synaptic changes are made permanent
activity dependent change in NMJ: silencing
silencing m. activity enhances polyneural innervation
The shingles rash follows the innervation pattern of nerves, and they tend to be restricted to a __________-__________.
single dermatome
area 2
size and shape
The _______ and _______ determine the speed of transmission in primary somatosensory afferents.
size, myelination
_______-______ fibers keep responding as long as the stimulus is present, meaning they are sensitive to the *duration* of a stimulus. ~think sustained touch, stretching mechanism
slowly adapting (fibers)
C fibers have a ________ diameter, are unmyelinated and the _______ pain experienced.
small, second
the ___________ contains nucleus and handle gene transcription and translation
soma (cell body)
Lesions at Brodmann's areas 3b impair:
somatic sensation
in _______ _______, different receptors are sensitive to distinct types of stimuli
somatic sensation
The receptive fields of S1 neurons produce an orderly map of the body on cortex, otherwise known as ____________.
somatotopy
Receptive fields
spatial domain in sense organs where stimulation excites or inhibits a pathway
small structure on dendrites
spine
synaptic changes with addiction
spine density increases more synaptic connections
where is actin found in the neuron?
spines of the dendrites
lewy bodies
stain for a-synucelin
Pacinian corpuscles are sensitive to the _________ and _________ of the stimulus.
start, stop
activity dependent change in NMJ: stimulation
stimulatin of m. accelerates elimination of extra inputs
withdrawal
stop drug use result in "overcompensation", opposite effects of drug itself ex. heroin produce constipation, withdrawal causes diarrhea
mechanosensitive ion channels open under the influence of:
stretch (distortion), pressure (any external force from linked extracellular proteins), shear, and displacement (internal force from linked cytoskeleton protein)
basal ganglia
striatum composed of: caudate and putamen globus pallidus subthalamic nucleus and SN
A glycine receptor antagonist is __________. It tends to disrupt breathing.
strychnine
associative learning: instrumental conditioning
subject learns to associate response, a motor act, with meaningful stimulus - behavior assoc with consequence
Peptides that act as inflammatory agents include __________, which is released by nociceptors causing ___________ and activated ________ cells.
substance P, vasodilation, mast
The synapses on neurons in dorsal horn is called the:
substantia gelatinosa
PD on SN DA
substantial loss of SN DA cell bodies
This location is where computation of the brain occurs, and is highly plastic due to being responsible for learning and memory, this part of the structure of a neuron is a major drug target. What is this structure?
synapses
_________ ________ describes the narrow gap that separates the presynaptic neuron from the postsynaptic cell, and where neurotransmitters are released from the ___________-________.
synaptic cleft, axon terminal
EPSP summation represents the simplest form of __________-_________ in the CNS
synaptic integration
The N- & P-type calcium channels are responsible for ___________ __________ in most neurons (presynaptic)
synaptic transmission
transfer of information at the synapse from one neuron to another is referred to as the:
synaptic transmission
V-SNARE
synaptobrevin. attached to the vesicle membrane
What is a calcium sensor that helps trigger vesicle fusion during zippering?
synaptotagmin
T-SNARE
syntaxin and SNAP-25. anchored to the presynaptic membrane
dependence
systems upregulate to compensate for drugs effects and maintain homeostasis
dorsal column-medial lemniscal pathway provides information on ________ sensation, and proprioception from the trunk and body via the _______-_______.
tactical (sensation), spinal cord
Trigeminal touch
tactile information from the head and neck related to the brain by the trigeminal nerve
Clossopharyngeal nerve
taste
Facial nerve
taste, facial expression
Thermoreceptors have the role of mediating the sensation of painful or non-painful __________ changes.
temperature
When the extracellular potassium concentration increases, the resting membrane potential depolarizes because:
the electrochemical gradient for potassium changes
Acetylcholinesterase
the enzyme that breaks down acetylcholine in the synaptic cleft
basal lamina
the extracellular matrix factors in BL causes rise in Ca in presynaptic terminal
The ___________, also known as pain nerves have free nerve endings that are activated by either an *intense* or *noxious* stimuli. They are located in the ____________ throughout the body, including the tissue, blood vessels, and bones/
nociceptors, (in the) periphery
types of procedural memory
non-associative learning: habituation and sensitization associative learning: classical and instrumental conditioning
effect of strabismus on binocularity
normal: most cells activated by both eyes strabismus: activated by either eye but not both, group 1 and group 5 active
The somatotopic map is _______ scaled to ______-______.
not (scaled to) body size
Group of somata (CNS)
nucleus
synaptic capacity
number of synapses with a neuron
Contralateral
opposite side
central visual system
optic n-> optic chiasm->axon from nasal retinas partially decussate-> optic tract to LGN of thalamus-> primary visual cortex forms retinotopic maps
Neurons are called "_______________" because information flows through them in one direction
polarized
Most nociceptors are:
polymodal
Emx2
posterior attractant, removing it results in more anterior expansion
Nociception informs the brain of:
potentially damaging stimuli
levodopa
precursor of DA, 10% crosses BBB remaining 90% converted to DA outside BBB and causes SE
ACh is released from the ____________ terminal
presynaptic
GABA and glycine are recycled by specific transporters on the ____________ terminal and nearby _______
presynaptic; glia
The trigeminal touch pathway consists of the communication of tactile information from the head and neck relayed by _________ afferents through the __________ nerve, otherwise known as cranial nerve ___.
primary (afferents), trigemincal (nerve), V
The increased pain sensitivity to already damaged tissue is referred to as:
primary hyperalgesia
parkinsonism
primary motor symptoms, can be caused by other types of disorders or a SE of certain meds (anti-psych)
excitatory synaptic transmission
primary receptors driving synaptic activity in visual cortex: AMPA and NMDA
Brodmann's areas 3b correlates to the _______-________ cortex. There is a *dense input* from _______-_______ nucleus of the thalamus. *electrical stimulation* of this are evoked somatic sensory experience.
primary somatosensory (cortex), ventral posterior (nucleus)
What is Brodmann's area 3B?
primary somatosensory cortex
In the dorsal column-medical lemniscal pathway, most _______ afferents travel through the dorsal root ganglia, and terminate in ________-________ nuclei of _________.
primary, dorsal root column (nuclei of) medulla
Multiple steps (synapses) occur to encourage the flow of information from the periphery to the cortex. There are 3 types of synapses: a) b) c) And each of these steps is an opportunity to *transform information*
primary, second order, third order (synapses)
differentiation
process by which cells take on characteristics of neuron
two point discrimination is the ability to distinguish the:
separation of two simultaneous pinpricks on the skin
development of cortical layers is orchestrated by _______?
radial cells
Opioid analgesics affect pain by: a) altering the brain's perception of pain b) decreasing excitability of sensory neurons c)
raising the pain threshold at the spinal cord level
The periaqueductal gray (PAG) projects to the __________-_________ where it releases serotonin (part of the inflammatory soup).
raphe nuclei
________ ________ fibers respond to stimulation with a burst of firing at the beginning and end of stimulation.
rapidly adapting (fibers)
Superior Colliculus
receives multiple visual sensory input from the retina and IC. control eye movement and head orientation
Mechanoreceptors of the skin are of multiple types that vary by: a) b) c)
receptive field size, preferred stimulus frequency, stimulus sensitivity
The _________-________ of S1 neurons produce an orderly map of the body on cortex, otherwise known as somatotopy.
receptive fields
__________ _________ is a drug that binds to a receptor and activates it.
receptor agonist
Inhibitors of neurotransmitter receptors, called ____________ ___________ , bind to the receptors and block (antagonize) the normal action of the transmitter
receptor antagonists
There are different __________ for different temperature ranges.
receptors
Inflammation is characterized by
redness, heat, pain, swelling
In primary hyperalgesia, because there is an increased pain sensitivity to already damaged tissue, there tends to be a ________ pain threshold, and an __________ intensity of pain experienced.
reduced, increased
What is a rapidly adapting fiber?
refers to either Meissner or Pacinian corpuscles. these fibers respond to stimuli with a burst of firing at the beginning and end of stimulation
What is a slowly adapting fiber?
refers to either Merkel disks or Ruffini cylinders. these fibers will keep responding as long as there is a stimulus present
substances and situation that improve survival tend to be
reinforcing
the following describes the: __________-____________-______________ the period of time following an action potential, when it is possible, but difficult, for the neuron to fire a second action potential, due to the fact that the membrane is further from threshold potential (hyperpolarized)
relative refractory period
nerve growth factor (NGF)
released by target tissue, taken up by terminals and transported to nucleus
brain derived neurotropic factor (BDNF)
released from postsynaptic neurons, taken up by Trk receptors on presynaptic side
Priming
repeated brain injury can lead to sustained microglia activated
growth of spines following LTP
repetitively activated by glutamate to induce LTP spine grows to accommodate more AMPA receptors
Homonculus
represents the density of sensory inputs from somatosensory cortex from each body region
polymodal nociceptors can...
respond equally to all kinds of damaging stimuli
Optic Nerve
responsible for vision
neural tube defects (NTDs)
anencephaly and spina bifida exact location and nature of defects reflect where neural tube fails to close
Pax6
anterior attractant, removing it results in posterior expansion
AADC
aromatic l-amino acid decarboyxlase L-dopa-> DA declines in PD so L-dopa less effective virus was genetically engineered to deliver AADC gene to striatum "on" time increased "off" time decreased maintained effectiveness for years
Calcium Activated Kinase 2
associated with long term potentiation as a result of being activated.
___________ form the blood - brain barrier and act to provide structural support for nerve cells in the CNS. These cells fill most of the spaces between neurons.
astrocytes
tripartite synapse
astrocytes wrap around synapses and connect to both pre and post synaptic cells
The electrical and chemical gradients for potassium are equal and opposite:
at the Nernst potential for potassium
where are the vesicles found in the neuron?
at the synapse
structural chances in brain with AD
atrophied cerebral hemispheres shrinkage(hippocampus)/ enlarged ventricles
A metabotropic antagonist is ___________.
atropine
Semaphorin 3A
attracts dendrites and repels axons forms a gradient
lateral
away from the midline
distal
away from the point of attachment
fasciculation
axon growing together stick to each other using cell-adhesion molecules (CAMs)
_________ is the part of a neuron that carries impulses away from the cell body, and can be greater than 1 m long
axons
posterior
back of body
Non-nociceptive primary afferents can also activate Melzack and Wall's gate. Non-nociceptive signals are activated ________ signal reaches the tract. This is an _________, bottom-up process which _________ pain.
before, ascending, reduces
Opioids interrupt peripheral ______-_____ pain messages from reaching the central nervous system.
bottom-up
What neurotoxins target the core complex?
botulinum toxin and tetanus toxin (both are proteases)
PD symptoms
bradykinesia (slow and small movements) tremor rigidity cognitive dysfunctions parkinsonism
Peptides that act as inflammatory agents include ________, which directly depolarizes __________.
bradykinin, (depolarizes) nociceptors
trigeminal touch pathway enters and decussates in the _______-_______.
brain stem
Gyri
bumps and ridges of the brain
Nerve
bundle of axons in PNS
rapidly adapting fibers respond to stimulation with a _______ of _______ at the beginning and end of stimulation.
burst of firing
axonal propagation can be sped up by...
by increasing lambda (Decrease axial resistance or Increase membrane resistance)
What is short term plasticity?
transient changes that affect on-going processing of information
_______-_______ ________ channels are channels expressed by thermoreceptors. Each thermoreceptor expresses one.
transient receptor potential (TRP channels)
Na+ channel opens ___________, meaning that it starts at a random time, and stays open for randomly (short) duration. And the ___________ always the same (all-or-none).
transiently; conductance
Ionic gradients are established by ______________. These structures bind ion(s) on one side, allows change of conformation and releases to other side
transporters
True or False: Action potentials can be elicited during the relative refractory period, but not the absolute refractory period.
true
True or False: Sodium channel inactivation prevents action potentials propagating retrogradely.
true
True or False: The thinnest of axons have the slowest conduction velocity
true
True or False: Very few ions must move in order to establish resting membrane potential.
true
Receptive field sizes varies with ________ of ________.
type (of) mechanoreceptor
differentiation of optic vesicles
vesicle-> optic stalk and optic cup optic stalk-> optic n. optic cup-> retina optic n. is part of brain NOT PNS
The electrochemical gradient decides the _________.
voltage
the capacity to do work
voltage
A __________-_________ enables an investigator to hold the membrane potential constant while transmembrane currents are measured.
voltage clamp
The bacterial K channel KcsA lacks S1-S4, indicating the lack of a:
voltage sensor
Voltage clamp is a powerful technique because of - It allows the study of _______-________ processes - It provides information about the membrane ________.
voltage-sensitive; resistance
Hydrocephalus
water on the brain
"winner takes all"
waves generated independently between eyes, one input is retained, other is eliminated
self-administration
way to measure reward in animals operant conditioning, train an animal to manipulate a "switch" to obtain a reward
How can we prove vesicle fusion?
we believe that pits are fusing with the membrane
drug addiction
when reward system goes wrong
small receptive fields consist of the: a) b)
Meissner's corpuscle, Merkel's disk
Modulation and regulation of pain is explained by the:
Melzack and Wall's Gate Theory
To depolarize a cell in voltage clamp from a resting potential of -65 mV to -20 mV, one should pass:
Positive current
When current is injected at one position on an axon, voltage changes measured at some distance away along the axon are generally which of the following?
Smaller, because of membrane leak
excitatory neurotransmitters
acetylcholine and glutamate
cortical white matter
carries all info to/from cortical neurons
Tectum
part of the midbrain responsible for sensory-motor processing and integration
3 phases to develop long-range projections
pathway selection: optic stalk-> chiasm: ipsi or contra? target selection: dorsal thalamus MGN or LGN? address selection: layer I-VI, retinoptic map
Shingles is a viral diseases that affects the ___________ nerves and causes blisters on the skin that ________ the course of the ________-________.
peripheral (nerves), follow (course), affected nerves
Long term potentiation
persistent increase in efficiency of synaptic transmission. can be induced by tetanus or pairing
dorsal
pertaining to the back
microglia
phagocytic cells that ingest and break down waste products and pathogens in the CNS
liking
pleasure and satisfaction
Where does cortical layer 4 receive input from?
the thalamus
Where does cortical layer 6 output to?
the thalamus
Two neurons have the same internal ionic concentrations and are bathed in the same external solution, yet differ in resting membrane potential. The two differ in ____________.
their permeability
Most nociceptors are polymodal, so they can therefore respond to:
thermal, chemical, and mechanical stimulis
filopodia
thin spikes that extend from lamellipodia - probe the environment -take hold of the substrate - pulls growth cone forward
Cerebellum
A large structure of the hindbrain that controls movement and coordination. error correction!!
differentiation of telencephalon
"endbrain" starts to grow posteriorly-> lies over and lateral to diencephalon-> become cerebral hemisphere-> white matter develop to connect hemispheres and telencephalon to diencephalon
The __________ channels are not voltage-dependent, and are responsible for resting membrane potential which allow ions to move along their gradient.
"leak" channels
hedonic value
"like" food because it feels good to eat
The voltage gating sensor are much more complex. The S__-S__ subunits are out to the side. The gating ring appears to be open. The depolarized S___ domain pushes on neighboring S5 and S6 to open.
(S)1-(S)4; (S)4
The S__ helical region of the K+ channel contains positively-charged amino acids, also known as a ____________-___________.
(S)4, voltage sensor
The approximate Nerst potential for Na+ is:
+60 mV
If the concentration of calcium is 1 mM outside the cell and 1 µM inside, then the Nernst potential for Ca2+ would be:
+92 mV
Conditioned place preference
- Way to measure reward in animals - Subj placed in one chamber paired with reward and not allowed to leave - Then paired with chamber with no rewawrd - After repeated pairing, subj is placed in middle to decide which chamber to go into
synaptic convergence
- binocular vision is result of convergence of R and L inputs from layer IV to layer III - exp driven synaptic rearrangements - arises from correlated patterns of activity from using vision - compared to segregation of domains which arises from spont activity - ocular dominance shift -rapid - reflect changes in synapses - binocular vision is highly susceptible to deprivation
differentiation of pyramidal neurons
- depends on intercellular signals - semaphorin 3A secrete by cells in marginal zone - result: dendritic end of cell points toward surface (marginal) while axons towards ventricles
working memory
- prefrontal cortex - differs from short term memory by: limited capacity, needed for repetition, very short duration
non-declarative memory
- procedural memory -skills, habits - no conscious recollection -solidifies with repetition and practice -not likely forgotten
segregation of retinal inputs of LGN
- starts with spont. discharge in utero - not driven by light -ganglion cells fire in quasi-synchronous "waves" in each eye
The approximate Nernst potential for Cl- is:
-60 mV
resting membrane potential is usually between _____ to _____ mV.
-60 mV & -70 mV
Suppose a cell has 15 mM chloride inside and 150 mM chloride outside, what is the Nernst potential for chloride?
-61 mV
The approximate Nernst potential for K+ is:
-80 mV
ocular dominance columns
-LGN neurons project to layer IV of striate cortex -Cortical columns consisting of neurons that receive signals from the left eye only or the right eye only -experiment use monocular deprivation
cortical neurons have very distinct morphology
-apical dendrites extend to pia -axon that extends in opposite direction
classical conditioning
-associative learning - associate stimulus that usually provokes specific response with 2nd stimulus that normally doesn't provoke response CS predicts US
differentiation
-cells are induced by environment to take certain "fates" -express particular channels/ receptors - extend axons/dendrites -cell and "regions" cane differentiate
H.M
-developed severe anterograde amnesia - working and procedural memory intact -could remember early life but couldn't form new declarative memories - bilateral removal of frontal temporal lobe including cortex and hippocampus
declarative memory
-memory of facts and events -conscious recollection -relatively easy to forget
migration of cortical layers
-migration sets up the layers -radial glial cells provide scaffold for migrating neurons -neuronal precursor cells move up this highway -cells in marginal zone secrete reelin -assembly of cortex completes and their arms retract -up to 1/3 of cells wander horizontally
segregation of input by eye
-nasal retina partially decussates -temporal stays ipsilateral
mechanisms of cortical synaptic plasticity
-neurons that fire together wire together -neurons that fire out of sink like their link - key is correlation
synaptic rearrangement
-occurs when pattern of connectivity changes - induced by neural activity and synaptic transmission -quality of visual environment postnatally determine quality of vision that develops
experience-dependent plasticity
-open eye columns expand in width while deprived eye columns shrink - can be reversed by opening eyelid and depriving the other eye
apoptosis
-programmed cell death leading to DNA fragmentation -regulated caspases -digested by macrophages
autism
-stereotyped behaviors, communication, and social interaction deficits - assoc with accelerated growth of brain-> reduced destruction of connections
long term potentiation (LTP)
-strengthening of synaptic transmission -NMDA may be Hebbian detectors where Ca entry triggers inc in syna strength
AMPAfication of synapse
-strong NMDA receptor activation floods postsyna dendrite with Ca - strengthens transmission -can split synapse in half, forming more synaptic contacts
Hippocampus
1 layer. control of learning, memory and spatial navigation
What is the pathway of the Dorsal Column-medial lemniscal?
1) A-beta primary afferents enter spinal cord at dorsal column 2) axons from 2nd order neurons from dorsal column nuclei continue via medial meniscus (axon cross) 3) connect with neurons of ventral posterior nucleus of thalamus 4)3rd order thalmaic neurons project to primary somatosenory cortex
How does active synaptic transmission occur?
1) Glutamate is reuptaken by transporters 2) ACh is degraded by enzymes
What is the trigeminal touch pathway?
1) Primary large diameter trigeminal axons 2) connect to 2nd order neurons in ipsilateral trigeminal nucleus of pons 3) cross to ventral posterior of thalamus 4) on to primary somatosensory cortex
causes of AD
1. abnormal low levels of Ach 2. accumulation of pathological protein, B-amyloid 3. hyperphosphorylation of MAP, tau 4. presenilin genes 5. alteration in cholesterol shuttling protein (ApoE4)
formation of NMJ
1. agrin deposited by growth cone 2. agrin bind to MuSK receptors (m. specific kinase) 3. clustering of Ach receptors in postsynaptic membrane
5 steps of cortical layers
1. cells in ventricular zone sends process up to pia 2. cell's nucleus migrates up to pia, DNA is replicated 3. nucleus settles back down to ventricular surface 4. cell retracts its arm 5. cell divides
formation of CNS synapse
1. dendritic filopodia contacts an axon 2. recruitment of synaptic vesicles and active zone proteins 3. recruitment of NT receptors on postsynaptic side -filopodia constantly formed and probing - adhesion molecules secreted by both sides to glue partners together
cycle of chronic relapse
1.drug use and abuse 2. tolerance and dependence 3. addiction 4. contemplating treatment 5. completing addiction treatment 6. relapse
horizontal migration
1/3 neural precursor cells know where to go due to Pax6 and Emx2
differentiation of forebrain
2 sets of secondary vesicles: telencephalic vesicles, optic vesicles remaining part of forebrain is diencephalon ("between brain")
retinotopic maps
2D surface of retina is mapped on 2D surface of LGN and striate cortex
There are approximately _____ genes in humans coding for the sodium channel.
9 genes
Mechanoreceptors of the skin have ______ fibers, with an approximate speed of 35-75 m/second.
A-beta (fibers)
The two classes of primary afferent fibers for nociception are:
A-delta & C (fibers)
_______________ describes a voltage minimum that is more negative than V(rest)
Afterhyperpolarization
Amygdala
Almond shaped structure thought to contribute to fear and aggression
Small molecule neurotransmitters are:
Amino acids; Catecholamines
If a voltage clamp apparatus reports an inward current, that could reflect...
An influx of positive ions
DA and reward related cues
Animals acquire operant behaviors much more quickly if cue is added DA release corresponds to cue presentation as strongly as to reinforce itself Transfer of DA firing to cue and behavior to get reward Cues are powerful motivators of behaviors
Which apoE combination has the highest risk for development of AD? Second highest risk?
ApoE 4/4, ApoE 3/4 ApoE 4/4 result in early onset AD
Negative reinforcement
Aversive component is removed when behavior is achieved
Axial resistance differs from membrane resistance in that:
Axial resistance is the resistance inside the axon, while membrane resistance is across the membrane
Conducts action potentials
Axon
3 basic groups of amygdala
Basolateral nuclei (BLA)- contains visual, auditory, gustatory, tactile Corticomedial nuclei- contains olfactory afferents Central nucleus
The sensory receptors for temperature, pain, and itch have ____ fibers, with an approximate speed of 0.5-2 m/second.
C (fibers)
The flow of current down an axon is best described using
Cable theory
What ion is necessary and sufficient for neurotransmitter release?
Calcium 2+
proximal
Closer to the point of attachment
Learned fear circuitry
Conditioning->sensory info-> BLA->converges to central nucleus->hypothalamus/PAG/cerebral cortex->response There are synaptic adaptations
corpus callosum
Connects the left & right hemispheres.
An example of an antagonist is...
Curare
The relative refractory period ends when delayed rectifiers:
Deactivate
When ion channels in the membrane open, the membrane resistance tends to __________.
Decrease
Receives inputs from other neurons
Dendrite
DREADDS
Designer receptors exclusively activated by designer drugs Mutated muscarininc receptors (1st ver out) No activity for Ach but activated by CNO CNO has no activity in animals that don't have DREADD Inject CNO to activate/inactivate neurons based on flavor of DREADD Long term activation, last hours, no tethering
Tetraethylammonium ion
Drug that blocks K channels should eliminate late component
plaques
EC deposits of amyloid beta in grey matter of brain remnants of degenerated axon terminals
somites
Formed in the mesoderm and appear as a bump on the surface of the embryo on either side of the notochord for 33 vertebrate and related skeletal m. it is what "somatic" motor nerves innervate
Preference
Formed when subject prefer chamber paired with reward
_______ dominant everywhere! Inhibition very important in shaping proper activity.
GABA
inhibitory neurotransmitters
GABA and glycine
_________ activity enhanced by: • Benzodiazepines (Valium, Xanax) • Reduce anxiety, sedative • Ethanol
GABAA
The ________________ equation predicts membrane potential more accurately
GHK (Goldman-Hodgkin-Katz equation)
Unusual neurotransmitters would be...
Gasses (NO) & Lipids (cannabinoids)
Spatial resolution
Genetic control restricts open to specific brain regions
Superior
Higher on the body, nearer to the head
The ________-______ ________ is a mathematical model that is used to describe the initiation and propagation of action potentials in neurons
Hodgkin-Huxley Model
The ___________ _________ in sodium channels is located in the loop between pore III and IV. This structure folds into pore of channel.
Inactivation gate
Reinforcement
Increases probability of behavior, measured by frequency,duration,magnitude,and latency of behavior Look at DA
Patient S.M- imaging studies
Indicate AMG role in processing fear: - Picture show fear expression active AMG - Neutal and happy expressions do not
Because the neuronal membrane at rest is mostly permeable to _____ , the membrane potential is close to E(____).
K+
The "delayed rectifier" channel is permeable to
K+
The gene sequence of _____ channels have 6 alpha-helical regions, S4 contains positively-charged amino acids (voltage sensor), and the region between S5 & S6 is referred to as a *pore loop*. In this channel 4 subunits assemble to form complete channel (tetramer).
K+ Channels
Why don't action potentials go backwards?
K+ channels open (hyperpolarized), as Na+ channels deactivate
AMPA receptors tend to activate rapidly, and permeable to _____ and to _____. It drives ________ electrical response.
K+; Na+; postsynaptic
a-synuclein misfolding
LB found in enteric NS start in lower brains tem (vagus), and olfactory bulb -> cortex a-synuclein can move between cells act like prion
Temporal resolution
Laser (ms control)
Lesions vs. stimulation of AMG
Lesions- flattened emotions and reduced fear and aggression Stimulation- increase attention/alertness, increase fear and anxiety
Amygdala lesions in primates result in
Less displays of fear and aggression Decrease in vocalizations and facial expressions
Inferior
Lower on the body, farther from the head
The discovery of "animal electricity" was made by
Luigi Galvani
Spinal Accessory nerve
Motor to neck and muscles
What kind of glutamate receptors are necessary for long term potentiation?
NMDA receptors. they mediate calcium entry!
Which ions set membrane potential in real cells?
Na+, K+, Ca++,Cl-
The resting membrane is permeable to _______ , _______ , and _______. At rest, these ions all have net flow across the membrane.
Na+, K+, Cl-
As the permeability of the membrane to an ion increases, the membrane potential approaches the __________ _________ for the ion.
Nernst potential
Optogenetics variation : light induced ____
Neuronal firing, inhibition of neural firing, recruitment of cell signaling molecules, sequestration, clustering to promote/strengthen signaling, gene expression
___________ convert glutamine back to glutamate (it reloads vesicles with glutamate)
Neurons
An example of an agonist is...
Nicotine
What neurotransmitter is used in the neuromuscular junction?
Nicotinic Acetylcholine. excitatory
the gaps between the myelin sheaths are called:
Nodes of Ranvier
large receptive fields consist of the: a) b)
Pacinian corpuscle, Ruffini's ending
Selectivity filter (K channel)
Oxygen-containing amino acids in pore
presenilins in AD
PSEN1/PSEN2 mutation increase y-secretase activity-> familial
natural reinforcers
Reinforcers that are naturally provided for a certain behavior; that is, they are a typical consequence of the behavior within that setting.
_______________ describes return of the cell to resting state, caused by reentry of potassium into the cell while sodium exits the cell.
Repolarization
The _____________ Theory states that nervous system is a *continuous cell network* physically connected to each other in a complex network of axons and dendrites
Reticular (theory)
The ___________ theory implied that nervous system is a ___________-_________ _______, was disproven by Golgi's silver technique.
Reticular (theory), continuous cell network
Positive reinforcement
Reward offered on expression of wanted behavior
The bacterial K channel (KcsA) channel has a similar pore loop in S__ & S__ , and has a constriction near to top on the extracellular side called a ____________- filter. It also has a constriction near the bottom called a ___________-_________.
S5 & S6, selectivity filter, gating ring
The congenital insensitivity to pain is a mutation in the ________ gene. This gene encodes Nav1.7, which is a voltage gated _____ ion channel.
SCN9A (gene); Na+ (sodium)
Emotional memory
Shown neutral, positive, and negative pictures Used PET to see that - Memory of emotional pictures was higher - Enhanced memory correlated with increased AMH activation
Hodgkin and Huxley's model revealed that the action potential reaches its peak when:
Sodium channels inactivate
Location of the nucleus in a neuron
Soma
Small, actin-filled structure
Spine
In a series of experiments, Curtis and Cole increased the extracellular potassium concentration and observed that the membrane potential of the squid giant axon depolarized. This happened because:
The Nernst potential for potassium depolarized
The ___________ __________ implied that the nervous system is made up of discrete cells, called neurons. It established that neurons may have complex structures and neurons are polarized.
The Neuron Doctrine
decussation
The anatomical crossing over of neurons from left to right
The Nernst potential is negative for potassium in a typical neuron because:
The concentration of potassium is greater inside than outside
growth cone
The growing tip of a neurite. Specialized to identify an appropriate path for neurite elongation.
gastrulation
The process by which a single-layered blastula becomes a three-layered gastrula. - forms a disk (embryo)
In voltage clamp experiments, the early inward current of the action potential ends because:
The sodium channels inactivate
The Goldman-Hodgkin-Katz equation differs from the Nernst equation in that GHK:
The two equations differ in none of the above respects
A negative current reported by voltage clamp is properly interpreted to mean:
There was an inward current
__________ are neurons that are sensitive to the changes in temperature.
Thermoreceptors
ventral
Toward the belly
Optogenetics
Use of light sensitive proteins to affect cellular function In NS takes form of firing or inhibiting neurons
Limbic system
Used to describe a set of structures though to contribute to emotion
Otto Loewi's experiment
Vagus nerve regulates heart rate by releasing a chemical substance
Contains and releases neurotransmitter
Vesicle
primary afferents enter at the dorsal roots, also known as the:
Zone of Lissauer
NMDA receptor
a glutamate receptor that also binds the glutamate agonist NMDA and that is both ligand-gated and voltage-sensitive
NMDA receptor
a glutamate receptor that is minorly involved in excitatory post-synaptic currents. permeable to calcium. modulatory. conductance is voltage dependent
AMPA receptor
a glutamate receptor that is the major component of excitatory post-synaptic currents
Blood Brain Barrier (BBB)
a highly selective mechanism that protects the brain
What is the calyx of held?
a large glutamatergic synapse in the CNS. very important for sound location. has a large presynaptic terminal. fast and reliable transmission
Brodmann's Cytoarchitectonic Map
a map that divides the brain into regions based on differences in layers. it concludes that similar structure leads to similar structure
periaqueductal gray (PAG) is:
a midbrain region involved in pain perception
Inferior Colliculus
a part of the midbrain that is involved in auditory processing
Tegmentum
a part of the midbrain that is involved in motor function and reward
a tetramer is:
a polymer comprising four monomer units.
inhibitory postsynaptic potential
a postsynaptic potential that hyperpolarizes the neuronal membrane, making a cell less likely to fire an action potential
amyloid hypothesis
abnormal cleavage of APP due to B,y-secretase activity, some familial mutations enhance B initiating event leads to plaques treatments: block B,y secretase but not a-secretase, enhance clearance of AB
cytoskeleton of a dendrite consists mostly of ___________.
actin
The primary job of sodium channels is the _________ ________
action potential
The voltage-dependence of sodium-channel activation contribute to
action potential threshold
Axons propagate __________ __________.
action potentials
congenital insensitivity to pain (CIP) tends to have a lack of nociceptor firing of _____ _____.
action potentials
firing rate describes the rate at which a neuron produces _______-________
action potentials (usually expressed in terms of spikes per second)
long-term depression (LTD)
active synapses are decreased in effectiveness eyelid close->loss of coord activity-> static/noise->weak NMDA activation->modest Ca->dec AMPA-> loss of influence over cortical neurons
correct alpha motor neuron innervation is dependent on
activity at NMJ
strong input to wrong layer "lose" because
activity doesn't correlate with the strongest postsynaptic response
induced pluripotent stem cell (iPSC)
adult cell taken from patient and reprogrammed into DA progenitor cells not foreign
__________ nerves bring to or lead towards an organ or a body part. An example would be a nerve carrying a message *towards* the CNS.
afferent
Transporters of ionic gradients work ____________ concentration gradients, making it so that ___________ is required and the process is relatively slow.
against (concentration gradients); energy (ATP is required)
Goldman-Hodgkin-Katz equation shows the membrane potential that results from the contribution of ______-______ that can cross the membrane
all ions
Opioid analgesics affect pain by: a) b) decreasing excitability of sensory neurons c) raising the pain threshold at the spinal cord level
altering the brain's perception of pain
addiction is often characterized as
an aberrant reward learning disease (plasticity)
neuronal patterning
biological process which cells in developing nervous system acquire distinct identities according to their specific spatial positions -controlled by signalling gradients throughout developing nervous system
cocaine
blocks reuptake of DA (DAT inhibitor) increase DA and produces feelings of pleasure increase approach and seeking behaviors
Somatic map is essentially a map of the:
body's surface
How is mechanoreceptor activation done?
by mechanosensitive ion channels in unmyleniated axon terminals that convert mechanical force to ion currents
__________ channels are composed of a single gene product
calcium
IP3 receptor
calcium channel in the ER
imprinting
classic example of critical period critical period= 24-48 hr
To terminate synaptic transmission, neurotransmitter must be removed from the ________. The _____________ (AChE) located in the cleft are responsible of the break down of acetylcholine
cleft; acetylcholinesterase
According to Melzack and Wall's Gate Theory, neural projections can _________ the gate. This is a __________, top-down process, which __________ pain.
close, descending, reduces
Ganglion
collection of nerve cell bodies in the peripheral nervous system
Synaptic integration is the process by which multiple synaptic potentials ___________ within ___________ __________.
combine; one postsynaptic neuron.
development of white matter tracts
cortical white matter corpus callosum internal capsule
two point discrimination depends on the _________ of mechanoreceptors in the skin, and the ________ of their receptive fields.
density, size
Inflammation is a response to __________-_________. There is nociceptor activation, and an __________ sensitivity with the release of inflammatory agents.
damaged tissue, increased (sensitivity)
nigra
dark
necrosis
death due to damage to cell cell swell and burst
deprivation experiments measure _________-________ input. An example of this would be the amputate finger (D3), and record the change that the area of the cortex that used to respond to D3, now would be redistributed to D__ and D__. Human limb amputations remap to face.
decreased sensory input
Opioid analgesics affect pain by: a) altering the brain's perception of pain b) c) raising the pain threshold at the spinal cord level
decreasing excitability of sensory neurons
Pacinian corpuscles respond to:
deep pressure and vibration
The ________ _______ in K+ channels are activated by __________. They do not inactivate. These help __________ action potential.
delayed rectifiers; depolarization; terminate
___________ are the branchlike parts of a neuron that are specialized to receive information.
dendrites
__________-__________ are small membranous protrusion from a neuron's dendrite that typically receives input from a single axon at the synapse
dendritic spine (or spine)
How can the smallest distance between 2 points be distinguished?
density of mechanoreceptors in the skin and the size of their receptive fields
Cortical maps are highly...
dynamic
effect of PD on striatum pathways
direct pathway less activated-> voluntary motor plan suppressed indirect pathway less suppressed-> inappropriate motor plans are less supressed
Guillian-Barre Syndrome (GBS)
disease due to demylination of PNS axons. acute. symptoms: muscle weakness, numbness, breathing difficulties, paralysis
neural circuits of liking and wanting
distinct and dissociable circuits for liking/wanting a reward
DDC inhibitors (carbidopa)
doesn't cross BBB increased L-dopa entry to brain dec peripheral SE of L-dopa dyskinesias
the periaqueductal gray (PAG) suppresses nociceptors in the ________ horn of the spinal cord.
dorsal (horn)
Axons of second order neurons from _______-_______ nuclei ascend via medial lemniscus, and also ________ here.
dorsal column (nuclei), decussate
dorsal column-medial lemniscal pathway enters the spinal cord through the ________-________ ganglia, and decussates within the ______ ______.
dorsal root (ganglia), spinal cord
The soma of the primary somatosensory afferents lie in the:
dorsal root ganglia
primary somatosensory afferents enter the spinal cord through the:
dorsal roots
spina bifida
due to folic acid supplement/ Vit B deficiency screen alpha-fetoprotein levels CSF can't flow normally hydroencephaly w/ shunt (possibly lifelong), braced legs, loss of bowel function, wheelchair confinement, frontal lobe/ executive function problems
synaptic remodeling
during learning LTP increases formation of new synapses while LTD leads to elimination of others
embryo is flat disk composted of 3 layers
endoderm mesoderm ectoderm
The descending regulation of pain can stimulate the release of ___________.
endorphins
What is long term plasticity?
enduring changes that can incorporate transient events into persistent alterations
Separating charges across the membrane requires ____________.
energy
Primary somatosensory afferents
enter the spinal cord through dorsal roots with cell bodies in the dorsal root ganglia
Flow of information from the mechanoreceptors of the skin to the cortex differs where they ________ and where they ________.
enter, decussate (cross to opposite side)
synaptic pruning
excess synapses made during development
The diversity of firing expression is very high in cortex, they can _________ _________ _________.
express different channels
integrin
expressed on cell surface; bind to laminin
ESC restoration of DA in PD steps
extraction from embyro expansion in vitro differentiation into progenitor neurons immature DA neurons
lamellipodia
flat sheets of membrane
cerebospinal fluid (CSF)
fluid that surrounds brain and spinal cord
neurulation
folding process in vertebrate embryos, which include transformation of neural plate into neural tube
Astrocytes
form blood brain barrier
Myelination is described as the:
formation of a fatty sheath around the axons
laminin
found in ECM
Myelination in the peripheral nervous system is done by ________.
glia
forms myelination
glia
Neurotransmitters that act as inflammatory agents include:
glutamate, serotonin, adenosine/ATP
NMDA receptors has calcium driving the intracellular signalling, and it needs both __________ (presynaptic) and __________ (postsynaptic) to activate. This receptor is known as the "coincidence detector," and is heavily involved in learning and memory.
glutamate; depolarization
___________ is a major excitatory neurotransmitter of the central nervous system. It is involved in just about everything! It is an __________ receptor. The subtypes of these ____________ receptors include: • AMPA receptors • NMDA receptors • Kainate receptors • Non-selective cation channels
glutamate; ionotropic; glutamate
hyperpolarization can be overcome by:
greater stimulus current
Sulci
grooves and folds of the brain (increase the surface area)
tract
group of axons in the CNS
nucleus
group of neurons in the CNS
In two-point discrimination, bigger receptive fields indicate that it is _________ to discriminate, and smaller being ________ to discriminate.
harder, easier
action potential current travels:
it varies for different axons, 1 to 100 m/s
slowly adapting fibers _______-_______ as long as stimulus is present.
keep responding
ventricular system
key to understanding the development of the brain structures
The information flow of the nervous system occurs in pathways, otherwise known as __________-_________.
labelled lines
Barrel cortex
large portion of the somatosensory cortex in rodents devoted to whiskers
LFS
low freq stim causes smaller elevation in Ca activates protein phosphatases= LTD
Somatotopic Map Plasticity
map changes based on loss or increased use
neurofibrillary tangles
masses of fibers in cell bodies protein malfunction leads to loss of ability to transport nutrients and enzymes along axon
Substance P activates _______ cells, which release histamine promoting swelling, and itch.
mast
___________ of the skin are of multiple types that vary by receptive field, size, preferred stimulus frequency , and stimulus sensitivity.
mechanoreceptors
Mechanotransduction occur with:
mechanosensitive ion channels
In the dorsal column-medial lemniscal pathway, axons of second order neurons from the dorsal-column nuclei ascend via __________-_________, and also decussate here.
medial lemniscus
MPTP
meperidine (MPPP) derivative, produces parkinsonism
__________ _________ are G-protein-coupled receptors whose primary action is to stimulate an intracellular biochemical response. These receptors are also known as ___________-______
metabotropic receptors; Muscarinic AChR
G-protein-coupled receptors are called _____________ receptors. These recetprs trigger ___________ __________ cascade, and tend to have complex effects in general.
metabotropic; intracellular signalling (cascade);
tau
microtubule associate protein (MAP) regulates MT in axons
Transport of materials within axons and dendrites occurs along:
microtubules
Dendrites contain __________. They receive input at the synapses, and these synapses are often formed into _________.
microtubules, spines
drug of abuse either
mimic NT or alter proteins that affect their levels
PD starts in gut
misfolded a-synuclein in guy leads to cascade of misfolding in endogenous protein in the brain symptoms better model human PD than MPTP loss of DA neurons runs up vagus nerve: vagotomy prevents spread PD patho req endogenous a-synuc
A metabotropic agonist is _____________.
muscarine
Endocannabinoids
natural, marijuana-like substances produced by the body
appetitive value
need to eat to satisfy hunger, consummatory
Group of axons
nerve
monocular deprivation
one eyelid is sealed closed ocular dominance columns
synaptic stabilization
only those retinal terminals that are active at same time as postsynaptic LGN target neuron are retained Hebbian modification synapse is strengthened when retinal activity drives a postsynaptic LGN
Nociception does not equal ________.
pain
Nav1.7 channel helps initiate action potential in __________ _________.
pain neurons
Nociceptors can be activated without _______, and people can experience pain without _________.
pain, nociception
olfactory bulb
pair of vesicles sprout off the ventral surface as telencephalon differentiates
neural plate
part of ectoderm that gives rise to nervous system
neuronal development basic steps
proliferation migration differentiation
addiction is
propelled by adaptations in "wanting" circuits
area 3a
proprioception
differentiation of neural tube
prosencephalon/ forebrain (rostral end) mesencephalon/ midbrain rhombencephalon/hindbrain (caudal end) rostral end of neural tube develops into brain which is derived from 3 vesicles caudal neural tube become SC
Lipids that act as inflammatory agents include __________ and _________.
prostaglandins, endocannabinoids
prion
protein that has ability to spread by inducing normal forms to misfold
stem cell derived neruons
provide renewable source of DA neurons
dorsal column-medial lemniscal pathway
provides information on tactile sensation and propriception from the trunk and body via spinal cord
synaptic refinement
pruning decreases unnecessary synapses
the periaqueductal gray (PAG) _________ nociceptors in the dorsal horn of the spinal cord.
suppresses
Pacinian corpuscles do not respond to _________ pressure due to the capsules *slipping* past each other dissipating the deformation of the nerve ending.
sustained (pressure)
__________ refers to the junction where information is transmitted from one neuron to the next.
synapse
connection between neurons
synapse
Area 1
texture
thalamic and cortical development
thalamic input is needed for proper cortical development
In the dorsal column-medial lemniscal pathway, the third order __________ neurons project to the __________ somatosensory cortex (S1)
thalamic, primary (somatosensory cortex)
the spinothalamic (anterolateral) pathway projects directly to the __________ after decussation.
thalamus
diencephalon differentiates into
thalamus and hypothalamus
The spinothalamic (anterolateral) pathway diffuses through projections in the _________ and __________.
thalamus, cortex
THe amount of cortical space dedicated to a body region depends on:
the amount of use
What is a dermatome?
the area of skin innervated by the dorsal roots of a single spinal cord segment (one to one relationship)
rapid adaption of pacinian corpuscles results from?
the capsule that makes the corpuscle sensitive to on/off activity & insensitive to sustained activity.
Forebrain
the cerebral cortex
Two synaptically connected neurons are separated by
the cleft
The Golgi silver stain used by Ramón y Cajal reveals:
the complete structure of single neurons
congenital insensitivity to pain
the condition of being born without the ability to perceive pain
How do the two hemispheres communicate?
the corpus callosum
Layered organization of neurons
the cortex
Ohm's law describes the relationship between
the current in a circuit = the voltage difference divided by resistance
The equilibrium potential for any ion (E-ion) is equal to
the electrical potential inside the cell that exactly counteracts the concentration gradient of that ion
The resting membrane potential usually differs from the Nernst potential for potassium because...
the membrane is permeable to multiple ions
Alzheimer's disease (AD)
the most common cause of major NCD, characterized by gradual deterioration of memory and personality and marked by the formation of plaques of beta-amyloid protein and tangles of tau in the brain
What will happen if you remove a capsule surrounding a Pacinian corpuscle?
the nerve becomes a slow adapting response
Ramón y Cajal discovered that
the nervous system is made up of discrete cells.
enteric nervous system
the nervous system of the digestive tract
Excitatory post-synaptic potential
the neuron is more likely to fire action potential. always depolarizing
Pyramidal cells
the primary cells of the cortex. they are excitatory
Sensation
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
What is sensory adaptation?
the progressive loss of receptor response as exposure to a stimulus is prolonged
What is the somatsensory organ in the body?
the skin
radial glial cells
thought to be scaffolding cells are neural progenitors/ multipotent stem cells
Meninges
three layers of connective tissue in which the brain and spinal cord are wrapped (dura mater, arachnoid membrane, pia mater)
critical period
timeframe in which plasticity can happen
neural crest
tissue from cells that are pinched off the ectoderm and come to lie on either side of neural tube (laterally) -> give rise to all neurons with cell bodies in PNS
addicts seek drugs
to not feel bad; not because they want to feel good
drug addiction stats
tobacco and alcohol causes the most harm most people who try drugs do not become addicted
Hypoglossal nerve
tongue movement
ApoE4 in AD
too much AB is bad normal ApoE is needed to clear AB mutants lead to AB accumulation and AD
Descending regulation of pain is by the ______-______ influence of the periaqueductal gray (PAG).
top-down (influence)
Considering that the dorsal column-medial lemniscal pathway provides *feedback* from *primary somatosensory cortex (S1) back to thalamus & brainstem,* it can be said that this is a _____-_____ processing. So information is _________ at each step.
top-down (processing), transformed
Afferents remain segregated from the ________ pathway.
touch (pathway)
Mechanoreceptors respond to:
touch, pressure, vibration, stretch
medial
toward the midline
C fibers are (myelinated/nonmyelinated).
unmyelinated
mechanoreceptors are the ____________ nerve endings of primary sensory afferents.
unmyelinated (nerve ends)
What is a mechanoreceptor?
unmyelinated nerve endings of primary sensory afferent sensitive to physical distortion of the skin
grey matter are the:
unmyelinated neuron cell bodies and short, unmyelinated axons
spina bifida in utero interventions
uterus removed from body so that back is exposed close dura, muscle, and skin maternal health risk risk of premature birth now standard care
The dorsal column-medial lemnsical pathway synapses on the neurons of the _________-________ nucleus of the ___________, which is *contralateral* in aspect.
ventral posterior (nucleus of the) thalamus
The trigeminal touch pathway decussates and travels to the ________-_______ (VP) of the thalamus onto tertiary order neurons, where it goes on to _________-________ cortex (S1).
ventral posterior (of the thalamus); primary somatosensory cortex
development of ventricles
ventricles provide roadmap to structure telencephalon lies over and lateral to diencephalon result in lateral ventricles and 3rd ventricles
2 layers of the early cortex walls
ventricular zone (close to ventricle) marginal zone(close to pia)