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137 Cards in this Set
- Front
- Back
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T1 vs. T2
when do you use one over the other? |
T1: CSF dark
T2: CSF bright T1: pricise, corpus callosum thinning in FAS T2: stroke (better with T2-flair), MS |
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What is the utility of diffusion-weighted T2?
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stokes show up immediately
show permanent white matter damage |
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when are the times you want to want to use CT?
what does CSF, white matter and grey matter look lik in CT |
Acute stuff, blood bone BBB
CSF: dark, white matter: medium, grey matter: light |
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differentiate and give an example of the following:
archicortex paleocortex neocortex |
oldest to youngest: paleo, archi, neo
paleo: 4 layers, RHINECEPHALON!!!, PYRIFORM CORTEX (cortical amygdala, uncus, and anterior parahippocampal gyrus), OLFACTORY BULBS archicortex: 3 layers, hippocampus, fornix neocortex: 6 layers, cerebral cortex, insula, corpus striatum (striated) |
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pyrimidal cells vs. spiny stellate cells
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pyramidal: output axons (small in layers 2 and 3, large in 5 and 6)
spiny stellate: interneurons; layer 4 (granule layer) |
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what cortical layer (1-6) receives thalamic input)?
output: what layers sends to opposite hemispheres, subcortical structures, feedback to thalamus? |
input: layer 4
output to opposite hemispheres: 3 subcortical structures: 5 feedback to thalamus: 6 |
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define and differentiate association, commissural and projection fibers.
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association fibers: connect cells w/in same hemisphere
commissural: connect cells to equivalent on differernt hemisphere projection: connects to different brain type |
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what do all of the following have in common? what does each do:
U fibers superior longitudinal fasiculus uccinate fasiculus infereor fasiculus |
association fibers
U: gyrus to adjact gyrus SLF: frontal-parietal-occipital uccinate fasiculus: frontotemporal inferior: occiptotemporal |
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what do all of the following have in common? what does each do:
corpus callosum anterior commisure posterior commissure |
commissural fibers
corpus callosum: cortex anterior: temporal lobe (smell) posterior: pretectal area of diencephalon (vision) |
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what commissural fibers are important for the bilateral pupillary reflex?
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posterior commissure
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what do all of the following have in common? what does each do:
internal capsule fornix |
projection bundles
internal: thalamus-cortex connection, cortex-brainstem/spinal cord connection fornix: hippocampus-mamillary bodies of hypothalamus |
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For the following thalamic nuclei, name the afferents and efferents:
anterior |
mammillary body to anterior nucleus (NA) to cingulate gyrus
limbic system |
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For the following thalamic nuclei, name the afferents and efferents:
ventroanterior/ ventrolateral |
cerebellar red nucleus (dentate) to ventrolateral to premotor cortex
basal gangilia to both to promotor cortex |
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For the following thalamic nuclei, name the afferents and efferents:
ventro-posterior |
posterior funiculus/lateral funiculus/trigeminothalamic tract (somatosensory input from limbs, trunk and head)
to ventral posterior nuclus to postcentral gyrus (somatosensory cortex) |
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For the following thalamic nuclei, name the afferents and efferents:
medial geniculate body and lateral geniculate body |
medial: inferior brachium to MGB to transverse temporal gyri (auditory cortex)
lateral: optic tract to LGB to striate area (visual cortex) |
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differentiate the following thalamic nuclei:
mediodorsal nucleus vs. lateral dorsal (lateral pulvinar) nucleus |
medial: frontal association cortex
lateral: parietal, occipital, temporal association cortex |
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axons:
netrins vs. semaphorins |
netrins: guide axons across hemisphers
semaphorins: stop growth (also Robo) |
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differentiate Trk and p75R as they relate to neurotrophin signaling
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Trk (tyrosine kinase receptor): binding promotes cell surviaval, outgrowth, plasticity.
trk decreases with age p75R: binding promotes cell cycle crest, cell death, neurite grown p75R increases with age |
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differentiate the two theories of neurodevelopment
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hebb's postulate: if you don't use it you lose it; you you use it, it will grow
activity-depdenty placitity: increase calcium, increase kinase, changes in histone-binding proteins changes in histones, changes in gene expression |
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what kinds of cells are essential for peripheral nerve regeneration?
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schwann cells and macrophages
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describe the link between olfactory bulb, hippocampus and adult neurogenesis.
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new nerve cells can grow
olfactory bulb: granule and periglomerular cells hippocampus: granule cells in dentate gyrus |
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what vitamin does GABA synth require?
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B6
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what are the three places in the brain that have the most sexual dismorphisms?
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preoptic
hypthalamus amygdala these places have most sexual dimorphisms |
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what is the sexual dismorphism in the two types of cells of onuf's nucleus?
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DM not different
VL is different (reduced cells in females) |
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is preoptic area larger in males or females?
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males
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what activates the hypothalamus in heterosexual women and homosexual men?
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androgens
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describe how estrogen has differential effects regarding sexuality and gender?
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it activates cingulate cortex in heterosexual women
it activates hypothalamus in hetero men and homo women |
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what stimulates GH release? inhibit release?
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stimulate: low BG, amino acids (arginine), exercise, GHRP (ghrelin!!)
inhibit: somatomedin released by liver (IGF-1); inhibits pituitary release and stimules SRIF neurons somatostatin (SRIF): decrease GHRH neurones |
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describe the short loop feedback of growth hormone release
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growth hormone released from the pituitary directly acts on SRIF neurons to increase its inhibiton of GHRH hormones acting on the median eminance
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what are the some effects of Growth hormone/ IGF-1 binding?
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increase skeletal growth
increase soft tissue growth anabolic, protein metabolism increase TAG hydrolysis increase BG (decerase insulin transport), increase FFA, increase AA, decrease urea |
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describe the regulation of cortisol secretion. when does it normally happen?
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diurnal input (suprachiasmatic nucleus) and stress both increase the CRH neruon release from the hypothalamus
pituitary release ACTH in the early AM to increase cortisol release from the adrenal |
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what is the precursor molecule to ACTH?
What is the precursor molecule for Cortisol? what enzyme is involved? |
ACTH: POMC, Pro-opiomelanocortin (POMC)
Cortisol: 11-Deoxycortisol (11BetaHydroxylase) |
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what is the function of purpose of long portal veins in the hypothalamus/pituitary?
what part of the pituitary is the target? |
NETTER 148
adenohpyophysis GnRH and CRH travel to pituitary so that there is non dilution of signal |
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what is the receptor target for ACTH? what is the immediate response? what is the end game?
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MC2R
increases LPL uptake to increase cortisol synth and release |
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what are the effects of glucocorticoids on carb, protein and lipid metabolism?
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carb:hyperglycemia (increased GNG, insulin resistance; decrease glucose transporters)
protein: increase plasma protein (from degradation in tissues, increased BUN) lipid: increase lipids in plasma (lipolysis redistributed to face and trunk) |
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what are the effects of glucocorticoids on CV, inflammation, lymph/immune, CNS?
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CV: maintenance of BP
inflammation: decreased local mediators, decreased COX,... lypmh: immunosuppression CNS: crosses BBB, so changes in levels change mood |
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(high/low) cortisol will result in hypOtension.
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low!
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what makes T4?
T3? |
T4: 2 DIT
T3: MIT + DIT |
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what are the 4 steps to make thyroid hormone?
what is used as a diagnostic tool to make sure things are working normally? |
1. UPTAKE (Na/I cotransport from B to I) RAIU used to measure this
2. OXIDATION (from I to A) pendrin to apical, thyroid peroxidase 3. STORAGE (in lumen), thyroglobulin, up to 3 weeks 4. RELEASE (A to B), ditch thryoglobulin |
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what percentage of thryroid hormone is bound?
what about the stuff that is unbound? |
99% bound; TBG specifc, albumin nonspecifically
only unbound can get into cell; it has a LONG HALF LIFE (slowly metabolizes) |
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describe thyroid hormone regulation.
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TRH from hypothalamus +
SRIF from hypothalmus - TRH/SRIF influence TSH release from pituitary TSH increases T4 and T3 synth from thyroid, both of these have negative feedback to both pituitary and hypothalamus |
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how do iodine levels affect TSH release?
how is this principle used to treat a "tyroid storm"? what is the known as? |
decreased iodine stimulates TSH release
increase (bigtime) iodine does to decrease thryoid hormone release for 1-2 days; WOLF CHAIKOFF EFFECT |
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what steps does TSH help out with in T4 synth and release?
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IT IS PLIEOTROPIC (HELPS WITH EACH STEP OF SYNTH AND RELEASE)
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what compounds metabolize T4? what is the prosthetic group?
what happens during starvation? |
deiodinases
selenium during starvation, deiodinase (Deiodinase I specifically) is inhibited thus lowering basal metabolic rate |
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what is the binding site for thryoid hormone?
what happens once it is inside the cell and what is the action? |
MCT8 receptor
once inside: converted to T3 and modulates gene expression |
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what are the major effects of thyroid hormone on the following:
metabolism CNS growth CV |
metabolism: increase metabolic rate
CNS: (young people) needed for normal CNS development Growth: (young people) increase skeletal growth CV: increase catecholamine and B adrenergic receptors in the heart; increase HR and contractility |
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what kinds of inhibitory neurons act on the nociceptive afferents of ALS? how are they activiatved?
how does opiods/morphine take advantage of this pathway? |
PAG in midbrain is activated
descending axons stimulate 5HT neurons in meduallary raphe nuclues axons from this nucleus project to substantia gelatinosa here Enkephalin containing inhibitatory interneurons inhibit nociceptive afferents of ALS the Enkephalin containing interneurons are the site of opiate analgesia |
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what is the difference between neospinothalamic fibers and Paleospinothalamic fibers?
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Neo: A-delta fibers: sharp, well-localized pain (magnitude and location)
Paleo: C fibers; deep/aching pain; intense affective component |
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motor cortex and supplementary motor area are involved in coordination of multiple muscle groups. which one (or combo) is recruited in the following:
single action complex action thinking about action |
single: motor
complex: motor and SMA thinking about action: SMA |
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what are the functional parts of the cerebellum?
name the nuclei, input and function for each? |
medial: VESTIBULOCEREBELLUM (fasigial nucleus, dense input from vestibular nuclei, corrects error in posture/balance)
intermediate: SPINOCEREBELLUM (interposed nucleus, dense input from spinal cord, corrects errors in body movement) lateral: PONTOCEREBLLUM (dentate nucleus, dense input from cerebral cortex, controls limbs and hand movements) |
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describe what signals go thru each of the cerebral peduncles?
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superior: output to forebrain
middle: input from pons inferior: input from cord --------------------------------------------------------- superior: mostly efferents to red nucleus and thalamus; afferent from trigeminal cerebellar (senses) and ventral spinocerebellar (non specific function) middle: cerebellar afferents from contralateral pontine nuclei inferior: mostly afferents from spinal cord and lower stem. efferents from dentate to inferior olive |
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differentiate climbing, mossy and parallel fibers of the cerebellum?
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climbing: axons of inferior olive, excitatory to purkinje cells (1:1)
mossy: axons of pontine/spinal/vestibular nuclei; synapse on granule cells parallel fibers: axons of granule cells that ascend to molecular layer (activate rows of purkinje cells) (1:lots) |
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what are the only efferent cells of the cerebellar cotex?
excitatory or inhibitatory? |
purkinje cells of molecular layer. descent to white matter
inhibitatory (GABA) |
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differentiate the function of the following cerebellar cortex cells:
basket stellate golgi |
basket: (spatial focus) lateral inhibition, sharpens excitation of PC along folium
stellate: (phasic quality): inhibition of recently activated PC (refractory) Golgi (temporal resolution): granule cells inhibited via feedback loop |
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what is the nuclei in the cerebellum that compares the cerebellar input with the processed cortical output?
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deep cerebellar nuclei
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describe the input and output of the vestibulocerebellum.
what 3 major descending tracts are affected from output? |
input from vestibular nuclei via ICP
processed in flocculonodular lobe output: MLF, vestibulospinal and reticulospinal tract MLF: control eye movements vestibulospinal: adjust muscle tone/reflexes reticulospinal: maintain posture and balance |
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briefly describe the 4 major spinocerebellar tracts?
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dorsal spinal cerebellar: proprioceptive from legs (nucleus dorsalis)/ Clarke; ICP
Cuneocereballar Tract: proprioceptive from trunk and upper limbs; ICP ventral spinocerebellar tract: SCP (samples descending axons) trigeminalcerebellar tract: sensory info from head (ICP, tectrocerebellar, mesencephalic nucleus of 5 |
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pontocerebellum:
ipsilateral/contralateral input ipsilateral/contralateral output which peduncle |
ipsilateral input
contralateral output MCP |
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describe the pathway involving the SN that controls horizontal gaze.
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striatum (caudate/putamen) actiavated and increases inhibitatory signal to SNpr
this inhibits the inhibitory signal to superior colliculus the superior colliculus is disinhibited and can achieve horizontal gaze |
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corpus striatum is..
striatium is ... |
corpus striatum: caudate, putamen, GP
striatum: caudate/putamen |
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what is the major cell type found within the striatum?
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cortical pyramidal cells
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describe the 3 phases of addiction.
what kind of learning and memory at each. what pathways are involved for each. how do you revert from level 3 to 2 and level 2 to 1 |
social use (reward learning, mesocorticolimbic)
regulated relapse (declaritive membory, regulated behavior, prefrontal cortex) compulsive relapse (procedural memory/habits, striatal habit circuitry) 3-->2 restore control 2-->1 replacement therapy |
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draw the addiction pathway
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poopyscoop
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drug abuse is related to an increase in ______ released from ______
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dopamine, VTA
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an imbalance of _______ released from the PFC to balance behavior via NuACC results in in the addiction habit taking over
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glutamate!!
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Addiction pathway:
what part of the brain is responsible for the "GO!"? what NT is used? what part of the brain is responsible for the "GO!"? what NT is used? what NT does NuAcc use? |
Go: Anterior Cingulate (Glutamate)
Stop: Orbial Cortex (glutamate), receives input from amygdala (glutatmate) NuAcc: stop |
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how do cocaine/heroin affect LTP and LTD?
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decreases synaptic plasticity
decrease LTP increases LTD |
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how does NaC affect LTP and LTD?
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restores plasticity
increases LTP and decreases LTD |
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Describe the dopamine levels in an adolescent relative to an adult.
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30% more in an adolescent
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describe the reticular activating system?
what NT is involved and what are the two nuclei that are responsible for it? |
AROUSAL SYSTEM: ACETYLCHOLINE
parabrachial (mibrain) and pedunculopontine (rostral pons) to thalamic relay nuclei/interlaminar nuclei from thalamus, projects to Cortex |
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what is the purpose of the median forebrain bundle with respect to sleep?
what NT are used? |
subtle arousal
NE, 5HT, histamine, oxexin, Ach |
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what is the origin of the following NT used in the median forebrain bundle for subtle arousal?
5HT NE Histamine Orexin Ach |
5HT: dorsal raphe (w/in PAG)
NE: locus coerulus Histamine: tuberomamillary recess Orexin: hypothalmus Ach: cuneform nucleus, mesencephalic RF; most downstream: basal nucleus of meynert |
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How does GABA made in the hypothalamus influence sleep (3 pathways that are inhibited?
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Reticular Activating system
Reticulospinal Tract Median Forebrain Bundle results in an increase of descending Ach |
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describe the activity of the following NT in the 3 states: asending Ach, NE and 5HT.
awake non-rem sleep rem sleep |
awake: all on
non-rem: all off rem: ascending ach on, ne/5ht off |
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describe what is happening at the following wave types:
Gamma Beta Alpha Theta Delta |
G-->D; decrease amplitude and decrease frequency
Gamma: binding info Beta: aroused/alert alpha: awake, relaxed theta: drowsy, sleepy delta: deep sleep |
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differentiate synchonized EEG and desynchronized EEG
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synchonized: sleep
thalamic neurons in oscillatory mode; inhibition from thalamic reticular cells; cycle of hyperpolarization and depolarization; synchrony desynchronized: awake thalamic neurons in tonic mode; cholinergic efferents (reticular activating system) stimulate the thalamus-->desynchrony |
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describe muscle tone in REM sleep;
describe the amplitude and frequency of EEG (hallmark of REM) what waveform spikes in REM, that also spikes in desyncrony and awake EEG |
increased muscle tone in and out of REM sleep
decreased amplitude, increased frequency PontoGeniculoOcciptal (PGO) waves spike, similar to desynchrony and awake EEG |
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what nuclei are responsible for circadiam rhythm and rapid eye movement?
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circadian: suprachiasmatic nucleu
rapid eyes: lateral geniculate nucleus |
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where does GABA come from in hypothalamus?
why is non-rem sleep considered active? |
activation of GABA in ventrolateral preoptic nucleus of anterior hypothalamus
responsible for low frequency of EEG inhibits histamine and cholinergic cells |
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describe the EEG in the following pathologies:
frontal lobe tumor encephalitis deep coma siezure brain death |
frontal lobe tumor: decreased f
encephalitis: decreased f deep coma: decreased f and A siezure: increased A brain death: no EEG |
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what face of memory occurs during sleep?
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consolidation
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describe the lateralization of the of the temporal lobes of the brain.
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left: language (plantum temporale)
right: emotion (insula and amygdala) |
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differentiate the following and associated brain regions involved in make a lasting memory:
encoding consolidation Long term storage retrieval |
encoding: new info learned and processed; requires attention (R parietal, left prefrontal), storage (hippo initially then association) and motivation (prefrontal and amygdala)
consolidation: while sleeping; gene expression, neuroplasticity (hippo and association cortex) long term storage: association cortex retrieval: frontal cortex, hippo, amygdala |
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what are the regions involved with info moving from cortex to the hippocampus, starting with neocortex
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neocortex, parahippocampal region, entorhinal region
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what is the entorhinal region?
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region is assoicated with input to the hippocampus
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what lobe is associated with attention?
working memory? |
attention: parietal cortex
working memory: dorsolateral prefrontal cortex |
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what are the three types of short term memory?
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sensory, short term (up to 30 seconds no hippo) and working
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what brain structure is involved with spatial memory?
emotional memory? |
spatial: hippo
emotional: amyg |
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what are the two types of long term memory?
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declarative (facts and episodic) (explicit)
non declaritive (implicit, subconsious) |
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what is the difference between associative and non associative non declarative memory?
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associative: require amygdala and hippocampus
requires multiple brain structures working together |
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describe simple conditioned response. how is it different if the response is associated with emotion vs. associated with skeletal muscle?
what brain structures are involved? is is associative and non associative non-declaritive long-term memory? |
associative w/ emotion: amygdala
associative w/ skeletal muscle: cerbellum |
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describe procedural memory; what is the hallmark pathology associated with this
what brain structures are involved? is is associative and non associative non-declaritive long-term memory? |
associative non declaritive long-term memory
subconscious how to ride a bike cerebellum, basal ganglia and motor cortex OCD!! (dysregulation of cortico-striato-thalamic) |
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describe non associative memory
differentiate habituation and sensitization. |
two things not related
LTP and LDP habituation: decreased response to stimulus sensitization: stimulus increases response |
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differentiate anterograde and retrograde amnesia?
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antergrade: no new info storage
retrograde: loss of memories before surgery (LTM inact tho) |
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what NT is used in working memory?
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dopamine from VTA, stimulates medial thalamus to dorsolateral prefrontal cortex
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What region of the frontal cortex that becomes very active in response to a motivational stimulus?
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anterior cingulate (in front of genu of CC)
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what specific part of the substantia nigra innervates the frontal cortex?
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VTA
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vision:
what is accomodation? what is the pathway in which the lens changes shape |
accomodation/refraction level needed the closer objects are
increased firing of ParaSymp to ciliary nerves to ciliary muscle contraction of ciliary muscle, which relaxes zonular fibers relaxation of lens-->more sperical |
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describe the conduction path from light to the optic nerve?
what are the two "interneuron" cells) |
light goes through all the layers and hits the pigment epithelium
rods/cones to bipolar cells (horizontal cells are interneurons) in outer plexiform layer INNER PLEXIFORM LAYERS: bipolar cells to ganglion cells which will continue to connect with optic nerve (amacracrine cells are interneurons here) |
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what is the difference between rod and cone cells
light sensitivity degree of photopigment chromaticity connections to bipolar cells acuity degree location relative to fovea |
rods: flatter, blunter with more discs; sensitive to dim light, monochromatic; high light sensitivity; lots of photopigment; convergent connections to bipolar cells; low acuity; peripheral retina
cones: thinner, tapered; increased acuity, need bright light, triochromatic; decreased photopigment, low sensitivity, 1:1 transmission to bipolar; in the fovea |
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describe the components of photopigment in dark and light settings
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dark: 11-cis retinal (bent) bound to opsin; ion permeability (inward current); depolarized;;;;;increased active photopigment
light: trans retinal (straight) moves out of opsin; g-protein opsin activated; hyperpolarized (no ion flow); decreased NT release;;;;decreased active photopigment |
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vision:
describe the difference between horizontal and amacrine cells. |
horizontal (btw photoreceptor and bipolar); sharpen contact; act as lateral inhibition
amacrine (btwn bipolar and ganglion cells); emphasize movement, phasic response |
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where are the brain does the lower field project? upper field?
fovea field? peripheral field? |
lower: above calcarine fissure
upper: below calcarine fissure fovea: most posterior peripheral: most anterior |
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where is the blind spot?
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at the optic disc
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describe the following types of foveation. which is conjugate and which is disconjugate:
saccadic smooth pursuit vestibulo-occulomotor vergence |
saccadic: fast, balistic (target)
smooth pursuit: following moving object across field; conjugate vestibulo-occulomotor: eyes move in response to head (eyes fix then head moves) vergence: eyes move together inward/outward as object moves away (disconjugate) |
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what kind of neurons are olfactory receptor cells?
describe the apical and basal parts? |
bipolar
apical: non-motile cilia basal: unmyelinated thru cribiform plate (synapse in olfactory bulb) |
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describe the signal transduction that occurs on olfactory receptor cells.
what happens as odor concentration increases |
carrier proteins in mucosa bring odor to cilia
as odor increases, firing rate increases odor binds receptor Golf on basal side of ciliary membrane released and activiates AC AC--->cAMP-->PKA-->opens sodium channels sodium comes in |
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describe how olfactory receptor cell afferents send signals to olfactory tract
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olfactory afferents synapse on dendrites of MITRAL CELLS
(glomerulus: specific to diff't receptor types) mitral axons project posterior-->olfactory tract |
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what are the two types of olfactory interneurons?
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granule cells: centrifugal feedback
periglomerular cells: glomerului selectivity |
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at what pitch is hearing painful: more than
what is the normal hearing sensitivity for humans? |
120dB
2-4kHZ |
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describe the pathway in the middle ear from tympanic membrane to oval membrane
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tympanic membrane
malleus incus staepedus oval membrane |
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why is the middle ear so prone to ear infections?
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eustachian drainage occurs here
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what is the purpose of the staepedus muscle?
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stiffens ossicle chamber, protection from loud noise below 2 kHz
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describe the fluid path of the inner ear.
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oval membrane. seala vestibuli. helicotrma. sceala tympani to round window
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which chambers in the inner ear have perilymph?
endolymph describe the ionic makeup for each what is the electric potential for each? what is the hair cell potential? |
perilymph: like CSF/ECF (high na)
endolymph: like ICF (low na) perilymph in seala vestibuli and seali tympani endolymph in sceala media perilymph: 0mV endolymp: 80mV hair cell: -45mV |
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what does resiner's membrane separate?
basilar? |
resiner: sv and sm
basilar sm and st |
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basilar membane
what kind of frequencies are best resonated at the base? apex? |
base: high frequencies
apex: low frequencies |
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auditory:
describe hair cell tranduction |
inner row of cells are the afferents to brainstem
basilar membrane vibrates and hair cell bends on tectorial membrane. bending depolarizes; hair cells release NT to afferent stereocilia binding causes an influx of K into inner hair cells. Ca gates open and calcium binding releases NT to to afferents K recycled to endolymph each fiber responds best to one frequency |
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what is the purpose of the 3 rows of outer hair cells in the basilar membrane of the ear?
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these are efferents from the superior olicary nuclei.
contraleral GOOD FOR SELECTIVE HEARING; NOISE DISCRIMINATION |
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what is the rhine test?
weber test? |
rhine test: air conduction should be better than bone conduction. failure: that means damage to conducting aparatus, ear canal or tympanic membrane
weber test: fork on skull. if one side is worse than the other then CNVIII damage to weak side. on forehead: (louder in affected is occlusion effect, soferted in affected (sensory neural loss0 |
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what are the odolinth organs?
info from SC? info from utricle/saccule? |
utricle saccule
SC: angular/rotational acceleration U/S: linear accelearation; gravitational (utricle: horizontal, saccule: vertical) |
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hair cells (towards/away) from kinocilia will result in depolarization of hair cells in vestibule?
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TOWARDS!!
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what is the kinocilia orientation in the utricle and saccule?
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utricle: towards midline; horizontal movement
saccule: away from midline: vertical movement |
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what is the substance in odolinth macula that make the membrane heavier (bigger response)?
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otoconia, calcium carbonate crystals
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where are the following tastes located topographically:
describe the signal conduction modalities for each bitter sweet/umami sour salty |
bitter: posterior tongue; metabotropic G protein
sweet/umami: anterior; metabotropic G protein sour: lateral; ionotropic (H+/cation influx) salty: most anterior; ionotropic (sodium influx) |
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what nuclei is associated with taste
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solitary nucleus
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what are the three nerves that convey taste from the tongue to the rostral solitary nucleus? how are they topographically conveyed?
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Anterior 2/3: (fungiform); CNVII
Posterior 2/3: (circumvallate, foliate); CN IX Pharyngeal area: (epiglottis); CN X |
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what is the purpose of afferents from the rostral solitary nucleus to the following:
reticular formation VPMpc thalamus Parabrachial nucleus |
RF: visceral reflexes
Thalamus: case of central fissure; conscious taste in cortex Parabrachial nucleus: affective/behavior respone to taste MFB |
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describe the function of the following hypothalamus nuclei:
preoptic nucleus (lesion) supraoptic nucleus (lesion) tuberal nuclei mamillary nuclei ventraomedial (lesion) paraventicular (lesion) posterior (lesion) |
preoptic nucleus: constant body temp (lesion HYPOTHERMIA)
supraoptic nucleus: water balance (lesion: diabetes insipidus) tuberal nuclei: histamine production mamillary nuclei: new LTmemory ventraomedial (lesion): SNS activatio (lesion: obesity) paraventicular (lesion): PNS activation, water balance (lesion: diabetes insipidus) posterior (lesion): temp change (lesion: hypothermia) |
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what is the difference between stria terminalis and stria medullaris?
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terminalis: amygdala to medial preoptic area
medullaris: lateral preoptic to habenular nuclei |
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what happens when you have a leasion in the preoptic area? caudal area?
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preoptic: hyperthermia
caudal: hypothermia |
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compare and contrast the two interneuron types in the retina
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Horizontal cells:
Directly on bipolar cells contrast in visual field Provide receptive fields for X-type ganglion cells (mediate discrimination of fine detail and contrasting areas, go with cones!) Project to LGN Amacrine cells (quick) On bipolar/ganglion cell junction Emphasize response to movement Phasic response of Y-type ganglion cells (Large, fast-conducting, phasic) Project to superior colliculus mediate eye-movement |
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describe the anatomy of an artherosclerosis?
where are statins supposed to help? |
Fibrous cap: SM cells, ECM, new vessels, foam cells
Necrotic center: cholesterol, calcium, and cellular debris STATINS STABILIZE FIBROUS CAP |
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SM cells move from _____ to _____ to begin to form an artherosclerosis.
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from media to intima
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when is CEA recommendation for prevention of stroke
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symptomatic: 70% occlusion, stroke, TIA
assypmtomatic: 70% occlusion, under 75yo, decreased risk of stroke by half |
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how should the circle of willis compensate for the newfound flow after CEA intervention?
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arterioles should constrict
to increase BP and O2 |
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how can you measure the autoregulatory mechansim?
what makes a bad one |
administer azetolamide (increase PACO2) and measure middle cerebral artery flow
vessels should dilate. <18% change bad |
