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NEURO FINAL
n/a
143
Health Care
Graduate
06/08/2009

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Term
frontal eye fields and superior colliculus are involved in what eye movement?
Definition
attentional saccades to the opposite side
Term
pretectal-posterior commissure area is involved in what eye movement?
Definition
upward saccade and gaze
Term
PPRF, periabducens, vestibular, and prepositus nuclei are involved in what eye movement?
Definition
slow eye movements
Term
dorsolateral midbrain reticular formation is involved in what eye movement?
Definition
vergence
Term
nucleus of the optic tract and accessory optic nuclei involved in what eye movement?
Definition
optokinetic reaction
Term
flocculus and paraflocculus involved in what eye movement?
Definition
slow eye movements and VOR learning
Term
describe the optokinetic reponse
Definition
involuntary movement of eyes to keep the visual field constant (i.e. when whole visual world moves, like looking out side window of moving car) mechanism comes from accessory optic nuclei (can occur without cerebral cortex)
Term
describe smooth pursuit movements
Definition
voluntary movements that keep an object foveated (only occurs with eyes open in light) requires lateral parietal and mid-temporal cortex
Term
what is the neural pathway for vergence movements?
Definition
striate cortex --> pretectum --> oculomotor and abducens nuclei
Term
describe corollary discharge.
Definition
oculomotor system sends message to posterior parietal and visual cortex telling it what changes of firing neurons to expect and not to consider these changes as due to movements of the extend world
Term
where do dopaminergic fibers originate and hwere do they distribute/terminate? what do they do?
Definition
originate in ventral tegmental area and substantia nigra --> travel thru lateral hypothalamic area --> terminate in nucleus accumbens and frontal lobes (in the lateralhypothalamic area involved in providing "reward" sensation to pleasurable hypothalamic functions. in meso-limbic pathway involved in reward sensation assocc with addictive drugs)
Term
where does cholinergic innervation originate and where does it terminate.
Definition
originates in septal nuclei, nucleus basalis. neurons spread diffusely thru brain thru nucleus accumbens, and to hippocampal formation
Term
where do seratogenic neurons originate and terminate. what does activation of this neuronal system do?
Definition
originate in raphe nuclei, terminate diffusely thru brain (activation involved in sleep/wake cycle and mood states)
Term
where do norepinephrine neurons originate and terminate?
Definition
locus coeruleus and distribute all over brain
Term
preoptic region of the hypothalamus involved in?
Definition
temperature control and reproductive function (male)
Term
suprachiasmatic (supraoptic) region of hypothalamus contains what 3 nuclei? what do they do?
Definition
suprachiasmatic nuclei (produces oxytocin or vasopressin with paraventricular nuclei, projects to and controls the post pituitary) also controls circadian rhythm; anterior hypothalamic area - control of parasympathetic nervous system, control of temp (helps body respond to increases in temp)
Term
tuberal region of hypothalamus has which 4 nuclei? what do they do?
Definition
lateral hypothalamic area (controls feeding and drinking); ventromedial hypothalamus (controls satiety and female reproduction); median eminence (controls anterior pituitary function); and arcuate nucleus (dopamine - modulation ofh hypothalamic hormone release)
Term
mammillary region of hypothalamus contains which 2 nuclei? what do they do?
Definition
mammillary nuclei (project to hippocampus, rolein learning); posterior hypothalamus (control of temp - helps body respond to a decrease in temp, control of sympathetic nervous system)
Term
what makes sure there is enough feedback control in the limbic/autonomic system?
Definition
connections frequently form a circuit and connections are frequently two-way
Term
hypothalamus-hippocampus pathway important for establishing?
Definition
learning
Term
hypothalamus-amygdala pathway important in establishing?
Definition
mediating emotion
Term
how do the ant and post hypothalamic nuclei control the sympathetic and parasympathetic nervous systems?
Definition
pathways connect ant and post hypothalamic nuclei with brainstem centers (reticular formation) which control the sym and parasym preganglionic nuclei in the spinal cord
Term
where are the central temp receptors for warm and cold?
Definition
anterior hypothalamus
Term
what happens in the event of temp increase?
Definition
activation of ant hypothalamus thermosensitive neurons --> parasympathetic sys increases body heat loss via peripheral vasodilation and sweating (motivated behavior too: seeking breeze)
Term
what happens if heat exposure is prolonged?
Definition
decreased release of thyroid releasing hormone (decreases body heat production by cellular metabolism)
Term
what does our body do when exposed to cold for prolonged amount of time?
Definition
releases thyroid releasing hormone, which increases basal metabolism rate thru increases in thyroid hormone
Term
what secretes interleukin-1 that causes reset in set-point body temp?
Definition
macrophages released by the pathogens
Term
what do the septal nuclei have to do with fever?
Definition
associated with anterior hypothalamus, thought to be associated with fever-induced compulsions
Term
what area of the hypothalamus stimulates feeding? what area is involved in satiety?
Definition
lateral hypothalamic area stimulates feeding, ventromedial hypothalamic area is a satiety center
Term
circadian rhythm dependent on what 2 rhythm generators? what do they each do/
Definition
suprachiasmic nucleus (controls cycles of SLOW wave sleep and skin temp) and pineal gland (controls cycles of REM sleep and body core temp)
Term
where does input to the superiorchiasmatic nucleus come from? where does input to pineal gland go?
Definition
SCN receives direct input from retina; whereas pineal receives indirect fibers from retina project to SCN thru intermediolateral cell column to superior cervical ganglion of the sympathetic nervous system to pineal gland
Term
what does melatonin do?
Definition
released during dark sleep cycle and is generally inhibitory to release of many hormones
Term
what is the molecular/cellular mechanism underlying the 24 hr rhythm in SCN?
Definition
light stimulates mRNA transcription of BMAL1 and Clock --> translated into protein--> combine and bind to regulatory DNA sequences (E boxes) in nucleus where they act as transcriptional enhancers --> synthesis of CRY and Per2 (proteins) on a time-dependent process --> CRY and Per2 associate, go to nucleus--> CRY inhibits B-C and Per2 begins cycle anew by stimulating transcription of new B and C
Term
Describe the sub-nuclei of the SCN
Definition
core - stimulated by light, can release peptides like calbindin which is necessary for rhythm; shell - releases vasopressin and maintains endogenous rhythm (light stimulates core to release Per1 and Per2 --> release GRP, substance P, and VIP which entrain shell neurons
Term
what does the limbic zone (cortical subsystem) consist of?
Definition
brain surface structures (septum, substantia inominata and amygdala) and allocortical (hippocampus = dentate gyrus and ammon's horn), subiculum, and primary olfactory cortex.
Term
paralymbic zone (subcortical system) consists of?
Definition
orbitofrontal cortex, insula, temporal pole, cingulate cortex, parahippocampal areas (pre and parasubiculum, entorhinal cortex, prorhinal and perirhinal cortices)
Term
homotypical association isocortex (heteromodal zones) (cortical subsystem) consists of?
Definition
dorsal prefrontal cortex, posterior parietal cortex, lateral temporal cortex. (broca's area in frontal lobe, wernicke's area at parietal-temporal junction)
Term
what is the homotypical unimodal association cortex for the visual system?
Definition
peristriate regions, inferotemporal cortex, and other parts of temporal lobe
Term
what are the homotypical unimodal association isocortex areas for the auditory systeM?
Definition
superior temporal gyrus and portions of medial temporal gyrus
Term
what are the homotypical unimodal association cortex associated with somatosensory system?
Definition
just posterior to primary somatosensory cortex (BA 5)and still more posterior in parietal lobe BA 7
Term
what is the homotypical unimodal association area for motor system?
Definition
premotor area (BA6, 8) and supplementary motor areas (BA6 on medial cortical surface)
Term
what does orbito frontal cortex do?
Definition
emotional issues, judging whether or not you should do something. damage? --> comportment (deficits in grooming, what you say to ppl, how you behave)
Term
what does the prefrontal cortex do?
Definition
impt in short term memory. damage? --> problems with executive function, serial performance, lose ability to organize large scale projects, sequencing of things, may lose emotional response
Term
what are the characteristics of broca's aphasia?
Definition
speak slowly with long pauses, content of speech meaningful, verbs conjunctions and prepositions left out, idea can be understood if sense is conveyd by individual words but not if the idea requires interpretation of complex grammar, unable to repeat any but simplest sentences (damage to BA 44 and 45)
Term
describes wernicke's aphasia.
Definition
(BA 22) speech fluent with normal intonation and normal rate of word production, content incomprehensible d/t errors in output (paraphasias). great difficulty understanding others, unable to repeat
Term
what is a conduction aphasia and what are the sx?
Definition
when area connecting wernicke's and broca's areas are physically separated. patient can speak fairly well and understand simple sentences, but cannot repeat. (also leads to pneumonic aphasias)
Term
what are transcortical aphasias?
Definition
when path to or from (or both) to a meaning center in the brain that assigns meaning to sounds are disrupted. ability to repeat a sentence is preserved! (bc direct tract from wernickes to brocas are intact)
Term
lesions of the right homolog of brocas area vs right homolog of wernickes
Definition
lesion of right homolog of brocas area = deficits in using tones that distinguish statements from questions; lesion of right homolog of wernickes area = deficits in interpreting the tonality and gestures of others
Term
visual information in BA 17, 18, 19 sent to two main targets. what are they and what do they do with this information?
Definition
temporal cortex for spatial signaling (processing objects, recognizing things); parietal cortex for object processing (spatial processing, being able to note where things are)
Term
bilateral lesions of junction b/w occipital and temporal lobes on medial cortical surface -->?
Definition
prosopagnosia (inability to visually recognize individual faces, specific object recognition)
Term
bilateral lesions of junction b/w occipital and parietal lobes on medial cortical surface lead to?
Definition
balint's syndrome (impair ability to orient and operate in personal space - 1) optic ataxia - using vision to reach for object 2) ocular ataxia - difficulty pointing eyes to intended target 3) simultagnosia - difficulty forming complete image of world - clear region jumps around
Term
damage to what area gives visual neglect?
Definition
posterior parietal damage (neglect contralateral side of parietal lesion)
Term
what does the arcuate nucleus of the hypothalamus do?
Definition
integration of many signals for increasing or decreasing feeding
Term
what are the 2 major outputs of the arcuate nucleus of the thalamus?
Definition
neuropeptide Y coreleased with agouti related peptide (increases feeding) and melanocortin coreleased with cocaine and amphetamine regulated transscript (decreases feeding)
Term
where are the cell bodies for neuropeptide Y & melanocortin and where do they project to?
Definition
cell bodies in arcuate nucleus, project to paraventricular nucleus of hypothalamus and lateral hypothalamus (causes animal to eat more and causes decrease in metabolism or eat less)
Term
melanocortin has 5 receptors, why? which is defective in some cases of child obesity?
Definition
MC4R for child obesity; melanocortin involved in more than just feeding (sexual, pigmentation, immune sys, inflammation, pain, learninig)
Term
explain significance of orexin (hypocretin) and melanin concentrating hormone
Definition
both produced by neurons IN the lateral hypothalamus (vs. neuropeptide Y and melanocortin which have cell bodies in arcuate nuc); increase feeding. both have effects on metabolism, BP and glucocorticoids, orexin important in sleep (lack --> narcolepsy)
Term
what part of brain affects food choice and learning what foods make us sick?
Definition
amygdala
Term
analytical aspect of food (taste, odor, texture) processed where?
Definition
orbitofrontal cortex
Term
what happens if we destroy the paraventricular hypothalamus?
Definition
lose ability to become satiated in short-term
Term
what happens if we destroy the lateral hypothalamus?
Definition
decreases in feeding and lowering of set point for maintaining body weight
Term
3 effects of leptin
Definition
food intake decreases, motor activity increases, basal metabolic rate increases (low concentrations of leptin has opp effect showing we have homeostatic feedback control of the amt of body fat)
Term
where are leptin receptors found?
Definition
arcuate and paraventricular nuclei, and beta cells of pancreas
Term
what does ghrelin do?
Definition
secreted by stomach A-like cells, increases feeding via stimulating neurons in arcuate nucleus to release neuropeptide Y and inhibits neurons that release melanocortin. blood ghrelin concentration decreases after eating and gradually increases until next meal
Term
what effect does CCK have on feeding?
Definition
released after consumption of a high fat meal --> produces satiety, slows gastric emptying, limits meal size. activity delivered by stimulating vagus which then affects the brain (cut vagus? effect largely lost)
Term
where does peptide YY come from and what effect does it have on feeding?
Definition
released from small intestine after a meal and via the vagus inhibits neuropeptide Y and stimulates melanocortin (inhibit feeding!)
Term
what is glucagon like peptide 1? where does it come from, what effect does it have on feeding?
Definition
is an incretin, released from small intestine by intraluminal glucose via vagus decreases feeding (release is glucose dependent)
Term
what is the pathway for intestinal hormones that inhibit feeding?
Definition
transit via vagus, projects to nucleus of tractus solitarious, projects to arcuate nucleus.
Term
how can insulin get to the arcuate nucleus and what effect does it have there?
Definition
via site in pituitary stalk where there is no BBB. increases in insulin concentration decrease feeding. (changes are slow and similar to leptin)
Term
what are brain areas we know are involved in memory storage?
Definition
neocortex, perirhinal cortex, hippocampus, amygdala (emotional), striatum, cerebellum (motor)
Term
what part of brain lesioned in win-shift task?
Definition
hippocampus - spatial learning, working (trial-specific) memory
Term
what part of brain is lesioned in win-stay task? why does another lesion (somewhere else) improve the learning rate?
Definition
striatum. hippocampal lesions improves learning rate bc instead of remembering spatial relationships, they're remembering the association (default behavior is to use spatial strategy to get food, HC lesioned? forced to learn associated strategy)
Term
what part of brain is lesioned in conditioned cue preference task?
Definition
amygdala
Term
does procedural memory depend on HC?
Definition
no
Term
2 paths in which conditional stimulus can reach the amygdala.
Definition
1. direct path - MGB --> lateral nucleus of amygdala 2. indirect path. MGB --> auditory cortex --> lateral nucleus of amygdala via external capsule
Term
how are conditioned fear responses controlled (i.e. pathway)?
Definition
lateral nucleus of the amygdala --> central nucleus of the amygdala --> projects to areas associated with the autonomoic nervous system (lesions of central nucleus prevent expression of conditioninig and impair unconditional responses)
Term
what does the schaffer collateral synapse connect?
Definition
CA3 axons synapsing on apical dendrites of CA1 pyramidal cells (where long term potentiation takes place)
Term
describe the concept of "cooperativity" in long term potentiation.
Definition
the requirement that the original EPSP is big enough so that high freq stimulation results in long term potentiation (persistent increase in size of EPSP). (how do we get EPSP big enough? increase stimulus strength! activate more and more axons to synapse on CA1)
Term
describe the concept of specificity in long term potentiation.
Definition
if two pathways are stimulated, only the one pathway with high freq stimulation will undergo LTP
Term
what is it about NMDA channels that allows them to detect the conjunction of presynaptic and postsynaptic activity and makes them ideal candidates for the molecular substrate of LTP?
Definition
dual glutamate plus depolarization requirement for opening NMDA channels.
Term
in LTP, what happens when the key NMDA channels are opened?
Definition
entry of Ca ions --> increase in conductance of K and Na via AMPA channels (increase in # of AMPA channels inserted into post-synaptic membrane or increased conductance) --> same amt of glutamate released by presynaptic terminal results in larger postsynaptic EPSP
Term
what's the difference b/w early and late phase LTP (mechanism)?
Definition
early phase yields EPSP increases that last ~2hrs (decay if protein synthesis blocked); late phase depends on protein synthesis but synaptic strength can increase and persist for days or weeks in vivo
Term
what mainly affects the appetitive and consummatory sexual behaviors in males respectively?
Definition
appetitive behavior affected by testosterone; consummatory behavior affected by lumbosacral cord
Term
medial preoptic area vs lateral?
Definition
medial is important for male copulatory behavior (not appetitive). lateral is important for thirst
Term
what are 3 physiological changes that can decrease sex drive in males?
Definition
decreased testosterone, damage to amygdala (decreased motivation), damage to mesolimbic dopamine system (decreases rewarded behavior)
Term
what effect does estrogen have on female sexual libido? testosterone?
Definition
estrogen initiates libido at puberty, but is less important in maintaining it. testosterone is a major cause of sexual drive and appetitive behavior (female brain more sensitive to testosterone than male - has increased libido with 1/10 the amount that males have)
Term
what structures in the female body produce testosterone?
Definition
ovary and adrenals, post-menopause it's all adrenals
Term
what are the important sites in female copulatory sexual behavior?
Definition
lumbosacral region, ventromedial nucleus of hypothalamus, medial preoptic area, central gray
Term
what hormones are "associated with monogamy" in males and females?
Definition
females oxytocin; males vasopressin
Term
how does learning some things under strong arousal (not necessarily stress) help us remember them?
Definition
strong arousal --> release epi --> epi works via vagus to affect nucleus of tractus solitarius --> affects amygdala --> increase many kinds of learning but explicit and implicit
Term
what area of brain has highest concentration of cortisol receptors? what is the significance of this?
Definition
hippocampus (means during chronic stress or cushings disease, brain atrophy occurs in area of HC)
Term
what 2 hormones are involved in mood?
Definition
corticotropin releasing hormone and adrenal corticotropic hormone (elevated CRH associated with depression and anxiety - measured in CSF)
Term
where olfactory receptor cells located and how are they activated?
Definition
located on membranes of the cilia on the olfactory knobs of epithelium. odorant binds and activates a secondary messenger system leading to depolarization of the receptor cell
Term
what are the five places that mitral cells project to?
Definition
anterior olfactory nucleus, olfactory tubercle, olfactory cortex, amygdala, entorhinal cortex
Term
connections from mitral cells eventually going to the hypothalamus do what?
Definition
bring about anatomical basis of endocrinological changes brought about by pheromonal stimulation
Term
connections of mitral cells eventually going to DM nucleus (dorsal thalamus) and then to orbitofrontal cortex do what?
Definition
form anatomical substrate for olfactory/odor discrimination
Term
connections of mitral cells eventually to entorhinal cortex and hippocampal formation dowhat?
Definition
provide basis for strong linkage b/w odors and episodic/event memory
Term
where do fibers from vomeronasal organ go?
Definition
project to accessory olfactory bulb --> amygdala --> hypothalamus (via stria terminalis)
Term
fungiform papillae - where are papillae, where are taste buds
Definition
papillae most numerous along front and sides of tongue (taste buds on top of papillae)
Term
where are vallate/circumvallate papillae located? where are the taste buds located?
Definition
circumvallate restricted to narrow zone across back of tongue (taste buds on side wall of papillae, in trenches)
Term
where are foliate papillae found? where are taste buds?
Definition
along postero-lateral edge of tongue (taste buds on side wall of papillae)
Term
where are filliform papillae found? where are taste buds?
Definition
filliform have no taste buds, cover over whole tongue
Term
anterior 2/3 of tongue innervated by?
Definition
chorda tympani (CN VII) ganglion cell in geniculate ganglion
Term
posterior 1/3 of tonuge innervated by?
Definition
glossopharyngeal (CN IX) ganglion cell in inf. petrosal gang
Term
epiglottis innervated by?
Definition
vagus (X) gang cell in nodose gang
Term
where is threshold low for sweet substances?
Definition
anterior region of tongue
Term
where is threshold low for salty substances?
Definition
anterolateral tonuge (i.e. fungiform)
Term
where are thresholds low for sour substances?
Definition
posterolateral tongue (i.e. foliate)
Term
where are thresholds low for bitter substances?
Definition
posterior regions (i.e. circumvallate)
Term
what is the mechanism for sweet taste transduction?
Definition
amino acid or sweet substance binds at apical membrane of taste cell --> activates G-protein coupled reaction --> increases cAMP --> cAMP-dependent phosphorylation of basolateral K+ channels; also receptor-mediated voltage independent Na+ selective amiloride sensitive channels in apical membrane (contribute to membrane depolarization --> summation --> AP)
Term
what is the mechanism for salt taste transduction?
Definition
depends on amiloride-sensitive, apical Na+ channels
Term
what is the mechanism for sour taste transduction?
Definition
depends on acid block of apical K+ channels
Term
what is the mechanism for bitter taste transduction?
Definition
involves receptor-mediated release of intracellular Ca++
Term
what cells detect pain in skin?
Definition
1.) normal delicate mechanoreceptors (fast) 2.) high threshold nociceptors (slow) req at least 10x greater stimulus intensity
Term
what excites/activates nociceptors?
Definition
tissue damage --> releases chemical substances (i.e. bradykinin, seratonin)
Term
what causes muscle pain?
Definition
"pain substance" created by muscle contraction with inadequate blood supply (bradykinin/seratonin)
Term
what causes tension muscle pain? (tension headaches, etc.)
Definition
certain kinds of muscle activity (i.e. tetanic contraction) --> increase in IM pressure --> blood supply compromised --> accumulation of "pain substance" --> further contraction = pain
Term
what is causalgia?
Definition
intense burning pain associated with nerve damage and local scarring (relieved by sympathetectomy)
Term
what is a possible explanation for chronic pain caused by carcinomatous invasion of nerve trunks?
Definition
chemically altered nerves
Term
what areas of brain elicit aversive responses (escape behavior)?
Definition
strong stimulation of central gray, nucleus gigantocellularis
Term
what happens with strong stimulation of medial thalamic nuclei?
Definition
unpleasant feeling not projected to any particular region of body, coupled with strong desire to escape. (normally, nocicieptive input excites medial thalamic region and ALSO classic somatosensory pathways leading to localization of painful input)
Term
what happens with WEAK stimulation of central gray?
Definition
analgesia. associated with release of endogenous opiates (stimulates large fibers which inhibit small nociceptive fibers)
Term
what is kluver bucy syndrome?
Definition
remove parahippocampal gyrus--> tame monkeys, hypersexual, put everything in mouth, hypermetamorphosis
Term
describe route 1 of limbic system
Definition
parieto-temporal occipital association cortices project to medial temporal lobe --> fusiform gyrus --> crosses collateral sulcus --> entorhinal cortex --> amygdala and hippocampus (outflow mirrors inflow --> medial temporal lobe --> prefrontal cortex --> premotor cortex --> motor cortex) for highly processed sensory info
Term
describe route 2 of the limbic system
Definition
thru brainstem --> thru lateral hypothalamus via medial forebrain bundle --> connections go thru fornix to get to hippocampus (other connections go straight, bypassing hypothalamus to get to orbital frontal cortex) (sensory & motor, for processing of unprocessed sensory information. largely hedonic behaviors, goal-oriented, consummatory behaviors involved with reward signals)
Term
describe route 3 of the limbic system
Definition
hippocampus/amygdala --> nucleus accumbens via fornix and stria terminalis --> ventral globus pallidus --> DM thalamus --> prefrontal cortex (also direct connection from nuc accumbens to goal oriented behaviors thru medial forebrain bundle)
Term
what are the components of the hippocampal axis of the limbic system?
Definition
hippocampus, cingulate gyrus, mammillary bodies, septal nuclei, anterior nucleus of the thalamus (fiber tracts: fornix, cingulum, mammillothalamic tract)
Term
lesions of the hippocampal axis of the limbic system result in what kinds of defecits?
Definition
declarative learning and memory, navigation and spatial representation, context (problems distinguishing one environment from another, guides behavior as far as knowing what's appropriate to do, etc.)
Term
components of the amygdaloid axis of the limbic system?
Definition
amygdala, DM thalamus, bed nucleus of stria terminalis, orbitofrontal cortex (fiber tracts: stria terminalis and ventral amygdalofugal pathway)
Term
lesions of the amygdaloid axis of the limbic system create deficits in?
Definition
social and emotional behavior, conditioned fear
Term
from hippocampus, fornix splits into precommissural fornix and postcommissural fornix. where does each of these project?
Definition
precommissural fornix --> septal nuclei, ventral striatum; postcommissural fornix --> anterior thalamic nucleus, hypothalamus, mammillary bodies
Term
what is the course of the mammillothalamic tract?
Definition
mamillary bodies --> anterior thalamic nucleus --> cingulate gyrus
Term
what is the direct connection of the amygdala to the neocortex?
Definition
amygdala --> orbital pre-frontal cortex (as in the 2nd route in the limbic system)
Term
from amygdala, fibers can travel in either ventral amygdalofugal path or in the stria terminalis.where do each of these paths project to?
Definition
ventral amygdalofugal path --> preoptic area, DM thalamus; stria terminalis --> bed nucleus of stria terminalis, medial hypothalamus, ventral striatum
Term
choroid of the eye is continuous with?
Definition
vascular core of the ciliary body and the stroma of the iris
Term
the optic cup extends forward as the?
Definition
ciliary epithelium and posterior epithelial layers of the iris
Term
what is the place principle of freq coding?
Definition
traveling waves of different freq move diff distances down the basilar membrane
Term
what is the volley mechanism?
Definition
(action potentials of the VIIIth nerve stay in register with oscillations of sound waves for freq up to 1000 cycles/sec) implies that potentially thep hoase of firing of the 8th nerve fibers can also contribute to freq discrimination
Term
what is the role of the superior olivary complex in auditory pathway?
Definition
projects efferent fibers of CN VIII to cochlea
Term
the three descending pathways of the auditory cortex terminate where?
Definition
MGB, sup and inf colliculi (which projects to sup olivary nucleus which projects to cochlea), pontine nuclei
Term
what is the type of bipolar cell that conveys the highest acuity and where is it located?
Definition
midget class of cone bipolar cells (found in foveal and parafoveal regions)
Term
visual regions in the parietal cortex detect what?
Definition
visually-guided movements. only fire when we have a reason to exect reward if we perform the proper behavioral sequence
Term
visual areas in the temporal lobe are mostly associated with?
Definition
object recognition - visual discrimination tasks, face recognition
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