Term
| afferent pathway for visual reflexes |
|
Definition
| retina > optic tract > brachium of superior colliculus > pretectal |
|
|
Term
| pathway pupillary light reflex |
|
Definition
| pretactal > ed west > ciliary ganglion > sphinctor pupilae on iris |
|
|
Term
| what is the consensual light reflex |
|
Definition
| both pupils constrist when light is shined on one due to crossing of fibers |
|
|
Term
| what happens in the eye to cause convergence |
|
Definition
| medial rectus contraction, pupillary constriction (sphinctor pupilae), thickening of lens (cilliary muscle) to increase refraction |
|
|
Term
| pathway for convergence reflex |
|
Definition
| retina and occipital cortex > superior colliculus > pretectal > ed west > cilliary ganglion > sphinctor pupilae and cilliary muscle |
|
|
Term
| pathway for pupillary dilation |
|
Definition
| pain / emotion > hypothalamus / amygdlia > medullary reticular formation > reticulospinal tract > intermediolaterall cell column spinal cord > superior cervical sympatetic ganglion > carotid plexus > dilator pupilae |
|
|
Term
| what is macrus gunn pupil, what diseases is this seen in |
|
Definition
light quickly moved to blind eye will cause dilation
optic neuritis and MS (demyelination) |
|
|
Term
| what occurs in holmes-adle pupil |
|
Definition
| one pupil dilates more slowly and accomodates slow due to cell death in cilliary ganglion |
|
|
Term
| what causes argyll robertson pupil, what is it |
|
Definition
constriction in accomodation but not light reflex, loss of pupillary light reflex due to pretectal or PAG lesion
CNS syphillis |
|
|
Term
| explain the development of the eye |
|
Definition
| day 22 optic sulci form in forebrain area of neural tube, neuro tube closes making optic vesicles, optic vesicles grow into the endoderm making optic stalk and lens placode, optic cup invaginates, inner layer becomes neural retina, outer becomes retinal pigment epithelium, hayloid artery forms in choroid fissure, distal degenerates proximal becomes central a and v of retina |
|
|
Term
| list the retinal layers in order |
|
Definition
1. inner limiting memebrane
2. optic nerve fiber layer
3. ganglion cells
4. inner plexiform layer
5. inner nuclear layer
6. outer plexiform layer
7. outer nuclear layer
8. outer limiting membrane
9. photoreceptors
10. retinal pigment epithelium
11. lamina vitera (buruch's membrane)
12. choroid layer |
|
|
Term
| what are the limiting membranes of the retina made of |
|
Definition
| muller's cells, microglial cells, astrocytes |
|
|
Term
|
Definition
or optic disc
bind spot, no photoreceptors, where optic nerve enters |
|
|
Term
|
Definition
center of retina in visual axis
yellow in red-free light
no vessels
acuity of vision |
|
|
Term
|
Definition
| depression in macula lutea, greatest acuity only cones, dark due to melanin in choroid, no vessels |
|
|
Term
|
Definition
| where functional retinal cells end |
|
|
Term
|
Definition
| anterior to ora serrata, 2 layers of columnar cells, outer layer is pigmented |
|
|
Term
| what are the functions of the pigmented eopthelium of the retina |
|
Definition
| reduces scattering of light, blood brain barrier, enhance visual acuity, remove membranous discs shed from rods and cones via phagocytosis |
|
|
Term
| explain the physical organization of the pigmented retina. what is on the apical and basal sides of the cell. what is connecting cells |
|
Definition
junctions connect cells to form blood retina barrier
1 layer of cuboidal cells
basal has nuclei and some pigment
apical has photoreceptors with pigment isolating them |
|
|
Term
| what are the functions and location of rods |
|
Definition
| see in low light, more in ora serrata, none in foeva |
|
|
Term
| what are the parts of rods what are their functions |
|
Definition
nucleus
outer segment: sheds fiber
inner segment: renews fiber, has more organells
fiber
disc: has rhodopsin
cilium: joins inner and outer segment |
|
|
Term
| what are the parts of rhodopsin, how does it work |
|
Definition
protein, opsin, retinal (from vit A)
quantum light changes its confuguration |
|
|
Term
| what happens in photoreceptors in the dark |
|
Definition
| Na goes in, RMP -30 mV, cGMP made |
|
|
Term
| what happens in photoreceptors in the light |
|
Definition
| light blocks Na enterance, membrane hyperpolarizes, cGMP stopped |
|
|
Term
| what is the function of cones and location |
|
Definition
| visual acuity, light associated with color, near macula |
|
|
Term
| what are the parts and function of them of cones |
|
Definition
outer segment: discs and double pigment layer
inner segment: larger than rod, renews fiber |
|
|
Term
| what is the function of the foevola, where is it, how does it do this function |
|
Definition
| concave reduces impediment of light passing them, absence of vessels scattering light, in the foeva |
|
|
Term
| what are the types of comes |
|
Definition
red, green, blue
have pigments that resemble rhodopsin (retinal and a cone opsin protein) |
|
|
Term
| what causes color vision deficiency, how are they classified |
|
Definition
| lack of an opison production, x-linked, defective green is called red/green |
|
|
Term
| what are bipolar cells between, what do they recieve input from |
|
Definition
between photoreceptor and ganglion
input from photoreceptors |
|
|
Term
| what are ganglion cells between |
|
Definition
| bipolar cells and optid disc |
|
|
Term
| some ganglion cells respond directly and dont send fibers down optic nerve, where are these fibers going |
|
Definition
melanopsin responds to blue light and sends info to midbrain and suprachiasmatic nuclei of hypothelamus
some go to rectum to mediate pupil constriction reflexes |
|
|
Term
| what are the association neurons |
|
Definition
| horizontal cells, amacrine cells, interplexiform cells,, interneurons |
|
|
Term
| where are horizontal cells, what are they between, what do they do |
|
Definition
outer bipolar zone
between photoreceptors and bipolar cells (inhibiting them) |
|
|
Term
| where are amacrine cells, what are they between, what do they do |
|
Definition
inner bipolar zone
axons between bipolar ang ganglion cells on interplexiform cells
inhibitory and excitatory |
|
|
Term
| where are interplexiform cells, what are they between, what do they do |
|
Definition
on bipolar cell bodies
between amacrine and bipolar cells
gives feedback to inner and outer retina |
|
|
Term
| what is the function of the retinal interneurons |
|
Definition
| lateral inhibition, enhance central transmission from dark to light retina regions, inhibit with GABA or glycine to fine tune signals |
|
|
Term
| what is the blood supply of the retina |
|
Definition
| central a of the retina, capillary layer of the choroid (diffuses to other retina parts) |
|
|
Term
| what can cause retinal artery occlusion |
|
Definition
emboli (from LA or carotid A plaque)narrowing at optic disc
small emboli in central A causes visual field deficit
toxicara cati and canis (from dog or cat intestine) cause granular lesion in rentinal a |
|
|
Term
| how is te eyefield divided |
|
Definition
| quadrents, hemifields, nasal, temporal, upper, lower |
|
|
Term
| what is the path from the retina to the cortex |
|
Definition
| retina > optic nerve > optic chiasm > optic tract > lateral geniculate > optic radiations in retrolenticular limb of internal capsule > geniculocalcarine tract > primary visual cortex |
|
|
Term
| where do the dorsal / superior (low visual field) fibers of the optic tract go |
|
Definition
| parietal and occipital cortex cuneate gyrus and calcarine sulcus |
|
|
Term
| what do the ventral / inferior fibers (meyers loop) (upper visual field) go to |
|
Definition
| temporal occipital love low calcarine sulcus (lingual gyrus) |
|
|
Term
| what tract comes off the retina other than the optic nerve, where does it go, why |
|
Definition
| retinohypothalamic > suprachiasmatic nuclei of the hypothalamus > synchronizes intrinsic circadian rhythm with light utilizing pituitary, gonadotrophin, pinealhormone, melatonin |
|
|
Term
| what takes over residual conciousness in destruction of the nuclei or cortex for the visual system, explain the pathway |
|
Definition
| optic tract > pulvinar nuclei > visual association cortex |
|
|
Term
| explain the location of the fibers from the macula in its course to the brain |
|
Definition
| makes up a large part of the lateral geniculate and cortex, posterior visual cortex |
|
|
Term
| what causes a bitemporal hemianopia, what is the symptom |
|
Definition
| dessucation interruption (often pituitary tumor), temporal vision deficit |
|
|
Term
| what causes a homonymous hemianopia, what are the symptoms |
|
Definition
| lesion interrupting optic tract, combinations of vision loss (sometimes with macula spared) |
|
|
Term
| why is the macula sometimes spared with vision loss |
|
Definition
| macula is close to middle cerebral A so when posterior cerebral a. is occluded it is spared |
|
|
Term
| where do fibers from rods project to in the lateral geniculate and cortex, what is the ultimate function of the cortex area |
|
Definition
| dorsal 2 mangocellular layers of the lateral geniculate and after primary visual cortex they go to the parietal occipital cortex (analyze motion and spation relation between objects and boxy) |
|
|
Term
| where do fibers from cones project to in the lateral geniculate and cortex, what is the ultimate function of the cortex area |
|
Definition
| ventral 3-6 parvocellular layers of the lateral geniculate and after primary visual cortex to the occipitotemporal association cortex (analyzes form and color) |
|
|
Term
| object agnosia: area of issue, symptom |
|
Definition
lesion in 18, 20, 21 (inferior occipitotemporal) in left hemisphere
can percieve but not identify objects |
|
|
Term
| prospangnosia: symptoms, cause |
|
Definition
can recognize faces but cant distinguish between them
bilateral lesion in mid occipitotemporal / fulsiform gyrus |
|
|
Term
| blaint's syndrom: cause, symptoms |
|
Definition
bilateral parieto-occipital junction
cant direct gaze at target due to saccades, cant do visually guided movements |
|
|
Term
| blind sight: cause, symptoms |
|
Definition
destructive lesion in geniculocalcarine tract
despite loss of concious vision light is detected |
|
|
Term
|
Definition
| REM that bring images to foeva. voluntary or reflex |
|
|
Term
|
Definition
| follow target to keep image on foeva, involuntary |
|
|
Term
|
Definition
| maintain eyes on target as it moves close or far (convergence or divergence) |
|
|
Term
|
Definition
| eyes momve in different directions |
|
|
Term
| what area controls horizonal eye movemnts |
|
Definition
| paramedine pontine reticular formation (PPRF) |
|
|
Term
| explain the path of control for horizontal eye movements |
|
Definition
paramedian pontine reticular formation > abducens nuclei > lateral rectus
AND
abducens nuclei > MLF > contrallateral oculomotor nuclei > medial rectus
AND
abducens nuclei > MLF > nucleus propostitus hypoglossi > keep eyes in position |
|
|
Term
|
Definition
| right abducens lesion, unable to gaze right with right eye |
|
|
Term
| right lateral gaze palsy: cause, symptoms |
|
Definition
| right paramedine pontine reticular formation lesion, unable to gaze right with both eyes |
|
|
Term
| left internuclear opthal moplegia |
|
Definition
| left MLF lesion, left eye wont gaze right, right eye has nystagmus on right gaze |
|
|
Term
| left MLF and left abducens nuclei lesion |
|
Definition
| right eye wont left gaze, left eye wont right gaze, nystagmus right eye right gaze |
|
|
Term
| one and a half syndrome: cause, symptoms |
|
Definition
lesion in paramedian pontine reticular formation. MLF, and VI nuclei
left eye wont gaze riht, neither eye will left gaze |
|
|
Term
| what areas control vertical eye movements, be specific on what each area controls |
|
Definition
| superior and inferior rectus and obliques, rostral interstitial nuclei of MLF (verticle gaze), interstitial nuclei of cajal (keep eyes in desired position) |
|
|
Term
| parinaud's syndrome: cuse, symptom |
|
Definition
lesion (peinoloma, hydrocephalus) compressing posterior midbrain and parietal area
impairment of verticle gaze, especially up |
|
|
Term
| what areas of the cerebral cortex control eye movement |
|
Definition
| gaze centers or superior colliculus, frontal eye field, parieto-occipito-temporal cortex |
|
|
Term
| what does the frontal eye field control, where is it located |
|
Definition
| saccadic movement, posterior middle frontal gyrus (8) |
|
|
Term
| how does the pariet-occipito-temporal cortex control eye movement |
|
Definition
| influenced via imput from the primary visual cortex and visual association cortex |
|
|
Term
| what is the vestibulo-ocular reflex (VOR) |
|
Definition
eyes move at equal velocity and amount in opposite direction of the head to keep image focused on the retina
supressed by cerebral cortex when awake |
|
|
Term
| how does the vestibulo-ocular reflex work |
|
Definition
| inner ear hair cells > vestibular ganglion > oculomotor, trochlear, abducens nuckei > efferent fibers to extra-ocular muscles |
|
|
Term
| explain the doll's eye phenomenon, why is this used |
|
Definition
| eyes turn oppoite to head turn and tilt in comatose patients, based on vestivulo-ocular reflex. vestibular apparatus, ncueli, nerve, MLF, abducens, and oculomotor nuclei are in tact |
|
|
Term
| explain how nystagmus works |
|
Definition
| involuntary rhythmic movement: slow in one direction (vestibular-ocular reflex mediated) and fast in the other direction (cortex mediated, gives name) |
|
|
Term
|
Definition
irrigate ear canal with head tilted 60 deg back
cold water causes nystagmus to opposite side, warm to the same side.
if comatose fast phase will be absent and the deviation will be toward irrigation when cold water is used.
shows cerebral hemisphere dysfunction |
|
|
Term
| what causes spontanous nystagmus |
|
Definition
| anticonvulsants, sedatives, lesion of peripherial vestibular apparatus, MLF, or cerebellum |
|
|
Term
| central vestibular nystagmus: symptom, cause |
|
Definition
| one way or two way eye movement, stimulation of hair cells on rotation or caloric irrigation |
|
|
Term
| peripherial vestibular nystagmus: symptom, cause |
|
Definition
| one way eye movement, stimulation of hair cells on rotation or caloric irrigation |
|
|
Term
| explain how do to post-rotational nystagmus is evaluated |
|
Definition
| patient sits in barnay chair head tilted 30 deg forward to put canals into plane of rotation, rotate 10 turns in 20 seconds and suddenly stop. |
|
|
Term
| what is the normal response to post rotational nystagmus |
|
Definition
| nystagmus left, fall right, dysmetria (past point), vertigo in left turning, 15-40 sec |
|
|
Term
| what are the parts of the outer ear, what are their functions |
|
Definition
auricle and external auditory meatus
collect and conduct sound to tympanic membrane |
|
|
Term
| what are the parts of the middle ear |
|
Definition
malleus, incus, stapes: conduct and magnify vibrations
tympanic membrane
eustachian tube to nasopharynx
chorda tympani
tensor tympani and stapedius |
|
|
Term
| what nerves not for hearing are in the middle ear, what are their function |
|
Definition
corda tympani: taste to anterior 2/3 of tounge. parasympathetic to submandibular and sublingual glands
VII: innervates stapedius connected to stapes
V: innervates tensory tympani connected to malleus
both dampen vibrations to protect cochlea < 1000 Hz
IX: sensory |
|
|
Term
| what is the blood supply to the middle ear |
|
Definition
| stylomastoid branch of the occipital or posterior auricular A. |
|
|
Term
| what are the parts of the inner ear cochlea |
|
Definition
heilocotrema, scala vestibuli, cochlear duct, spiral organ, scala tympani
2.5 turns around modiolus
endolymph and perilymph |
|
|
Term
| what is the function of the spiral organ of corti |
|
Definition
analyze frequency
localize pitch 20 Hz at apex and 20000 at base |
|
|
Term
| what are the parts of the inner ear |
|
Definition
| cochlea, bony labrynth of temporal bone, perilymph, membranous labrynths. endolymph |
|
|
Term
| what supplies blood to the inner ear |
|
Definition
|
|
Term
| what can cause conduction deafness |
|
Definition
interrpution of passage of sound through external or middle ear
wax
foreign body
otosclerosis
otitis media |
|
|
Term
|
Definition
| neogenesis of labrynth spongy bone around oval window causing stapes to fix |
|
|
Term
| otitis media cause and outcomes |
|
Definition
inflammation of middle ear
can cause meningitis and brain abcess |
|
|
Term
| sensorineural or preceptive deafness: cause |
|
Definition
cochlear nerve, central auditory connection, or chchlea disease
drugs, toxins, quinine, asprin, strep
loud noise (high frequency loss)
rubella infection in utero
cytomegalovirus
syphilis
prebycusis
acoustic neuroma |
|
|
Term
| prebyscus: cause, symptoms |
|
Definition
degeneration of organ of corti at basal coil of cochlea
high frequency loss with age (4000-8000 Hz) |
|
|
Term
| acoustic neuroma (schwannoma / neurilemoma): cause, symptoms |
|
Definition
peripherial nerve tumor in internal auditory meatus or cerebellopoitine angle
unilateral deafness and tinnitis |
|
|
Term
| neurotransmitters used in hearing |
|
Definition
| glutamate, asparatate, gaba, glycine, ach, various neuromodulators |
|
|
Term
| glytamate role in hearing and location |
|
Definition
AMPA receptors: excitatory, fast
NMDA receptors: excitatory, slow
allows Na and Ca into cell and K out |
|
|
Term
| asparatate role in hearing and location |
|
Definition
excitatory, fast
in cochlea |
|
|
Term
| GABA role in hearing and location |
|
Definition
inhibitory, fast
role in audition |
|
|
Term
|
Definition
|
|
Term
| explain the movement of sound through the ear to the stimulation of the cochlear nerve (detialed!) |
|
Definition
1. acustic energy goes into external ear
2. changes to mechanical energy at tympanic membrane
3. conducted and magnified, compensate midmatched impedance at ossicles
4. stapes move oval window change it to hydrodynamic energy as it moves fluid in labrynths
5. basilar membrane around hair cells move tectoral membrane
6. hairs mechanorecept the vibration of this movement
7. hair cilia bend due to fiber link movement
8. tension causes channels to open, Ca and K go into cell, cell depolarizes
9. electrochemical signal is sent to the cochlear nerve |
|
|
Term
| where are the cochlear nuclei, what are their functions |
|
Definition
dorsal lateral medullopontine junction
unilateral input
ventral: inferior to peduncle. horizontal lateralization
dorsal: next to acustic tubercle on floor of 4th ventricle. integrates somatosensory sound and detects spectral notches |
|
|
Term
| what are the general functions of the cochlear nerve (type of nerve, sounds heard, discrimination, etc) |
|
Definition
SSA
20-20000 Hz
discriminate 1-2 dB up to 120 dB
tonopic pitch localization |
|
|
Term
| once the cochlear nerve reaches the dorsal cochlear nuclei, where does it go |
|
Definition
| dorsal cochlear nuclei > lateral laminiscus > some may cross over on comissural fibers > inferior colliculus > medial geniculate > brain |
|
|
Term
| once the cochlear nerve reaches the ventral cochlear nuclei, what are its options, list them |
|
Definition
all will travel through trapezoid body > olivocochlear bundle > lateral laminiscus
then there is choices...
crossed uncrossed reflex (comes out of olivocochlear bundle)
superior colliculus
DNLL
VNLL
reticular formation
commisural fibers
inferior colliculus > medial geniculate > brain |
|
|
Term
| what is the superior colliculus involvement in cochlear nerve |
|
Definition
| mediates audiovisual reflexes |
|
|
Term
| what is the olivocochlear bundle involvement in cochlear nerve |
|
Definition
sends efferent fibers to the outer hair cells to regulate sensitivity, ehnance, and sharpen inhibition
crossed and uncrossed reflex |
|
|
Term
| what is the reticular formation involvement in cochlear nerve |
|
Definition
| short latency acoustic startle reflex pathway |
|
|
Term
| what is another name for the medial geniculate |
|
Definition
|
|
Term
| where is the inferior colliculus located, what nuclei is used for hearing |
|
Definition
central nuclei is used
external dorsal cortex, laterally |
|
|
Term
| what is the function of the lateral laminiscus in hearing |
|
Definition
spectral analysis: vowel detection, line spectracking
detect transients
measure timing of echoes |
|
|
Term
| how does hearing information travel through the lateral laminiscus and thalamus |
|
Definition
| acustic rdiation of internal capsule |
|
|
Term
| what is the function of the VNLL |
|
Definition
short latency acoustic startle pathway
transient detection |
|
|
Term
| where is the trapazoid body located |
|
Definition
| cuboidal pontine tegmentum of abducens transversed by CN VI |
|
|
Term
| what is the function of the trapazoid body, how is it regulated |
|
Definition
high frequency, sensitive bundle of axons
glycine inhibits |
|
|
Term
| what is the function of the superior olivary complex and its nuclei, how are they regulated |
|
Definition
sound localization, binural processing
lateral nuclei: high frequency, comparing ears, code of localization in asimuth. inhibited by glutamate and glycine
medial nuclei: low frequency, detect differences in arival of sound |
|
|
Term
| what makes the medial nuclei different from the lateral superior olivary nuclei |
|
Definition
larger
low frequency
disrupted in autistics
responds better to binural stimuli
detects differences in arrival of sound
1-2 spies on onset |
|
|
Term
| after fibers reach the DNLL or VNLL where do they go |
|
Definition
some go back to the lateral laminiscus to regulate it
some go the the inferior colliculus because they are normal hearing fibers |
|
|
Term
| what are the areas of the medial geniculate and their functions |
|
Definition
ventral: excitatory
dorsal
medial: multisensory arousal. excitatory and inhibitory |
|
|
Term
| what is the input and output from the ventral medial geniculate |
|
Definition
input: reticular nuclei of thalamus
output: primary auditory cortex |
|
|
Term
| what is the input and output of the dorsal medial geniculate |
|
Definition
input: periolviar nuclei, pericentral nuclei, external nuclei, lateral laminiscus, superior colliculus
output: primary auditory cortex, higher association area |
|
|
Term
| what is the input and output of the medial medial geniculate |
|
Definition
input: reticular nuclei of the thalamus
output:primary auditory cortex, higher association area, auditory association cortex |
|
|
Term
| where is the primary auditory cortex, what is its function, what input does it get |
|
Definition
transverse gyri of heschl (41-42) in lateral sulcus
high pitch localization, simple tones
contralateral input from III, V, VI
corticalfugal input from V |
|
|
Term
| where is the higher auditory association area, what is its function |
|
Definition
(39-40)
correlate sound to auditory streams, visual sensitivity |
|
|
Term
| where is the auditory association area, what is its function |
|
Definition
(22)
positive and negative bands alternate and sense signal differences |
|
|
Term
| where is the plantum temporale |
|
Definition
| in sylvian fissure extending into parietal operculum and inferior parietal lobe (22) |
|
|
Term
|
Definition
|
|
Term
| what is the function of barocha's area, where is it |
|
Definition
identify source of speech and meaning
ventral frontal lobe |
|
|
Term
| what is the function of cochlear fibers that go to the parietal lobe |
|
Definition
| spatial localization of source of sound, used for actions |
|
|
Term
| what does a lesion of the vestibular part of CN VIII cause |
|
Definition
| vertigo, disequlibrium, nystagmus |
|
|
Term
| what type of nerve is CN VII |
|
Definition
|
|
Term
| where is the inner ear, what are the cavities |
|
Definition
bony labrynth of temporal bone
cochlea, vestibule, semicircular ducts |
|
|
Term
|
Definition
| perilymph with membranous labrynth (contains hair cells and endolymph) |
|
|
Term
| what is in the semicircular ducts |
|
Definition
| 3 semicircular canals that have perilymph with kinetic labrynth in it (contains endolymph and hair cells of cristae ampularis) |
|
|
Term
| what is the function of the semicircular ducts |
|
Definition
| detect angular movement, acceleration, and deceleration |
|
|
Term
|
Definition
| perilymph with static labrynth (contains otlith membrane and hair cells of the caculae, utricle, and saccule |
|
|
Term
| what is the function of the vestibule |
|
Definition
detects linear acceleration and gravity
influences muscle tone to maintain equlibrium
static, potential, and tonic neck and righting reflexes |
|
|
Term
| what does perilymh communicate with, how |
|
Definition
| subarachnoid via perilymphatic duct of cochlear canaliculus |
|
|
Term
| where is the endolymph secreted and absorbed |
|
Definition
secreted by sitra vascularis of cochlear duct
absorbed in endolymphatic space sac |
|
|
Term
| what is the function of the vestibuloocular reflex, how does it work |
|
Definition
| stabilize images on retina during head movement by moving eyes opposite to head |
|
|
Term
| what happens if the vestibuloocular reflex is impaired, how is this tested |
|
Definition
difficulty reading
stimulate kinetic labrynth |
|
|
Term
| what are the possible causes for decerebate and decoraticate rigidity |
|
Definition
brainstem transection causing antigravity tone increase
vestibulospinal / pontoreticulospinal dysruption and role in control of extensor muscle tone
opisthotonos
lesion of internal capsule of cerebral hemisphere |
|
|
Term
| what are the symptoms of lesion of internal capsule of cerebral hemisphere |
|
Definition
flexed arms, wrists, fingers, abduction
extension, internal rotation and plantar flexion of legs
like chronic spastic |
|
|
Term
| what are the symptoms and treatment of opisthotonos |
|
Definition
arms extension abduction hyperrotation
feet plantar flexion, extension
treatment; destory vestibular nerve or nuclei (rhizotomy) |
|
|
Term
| what is vertigo, what is the cause |
|
Definition
whirling sensation or illusion of movement
cause: head position and nystagmus, cuprolithias of posterior semicircular duct (dislocation of utricular macular otliths) |
|
|
Term
| what is the cause and symptoms of meniere disease |
|
Definition
increased endolymph pressure
vertigo, tennitus, hearing loss, nausea, vomitting, pressure, nystagmus (fast to opposite ear) |
|
|
Term
| what is the cause and symptoms of labrynthitis |
|
Definition
bacterial, viral, toxin (alcohol, quinine), inflammation
unilateral: horizontal nystagmus to opposite side
bilateral: no nystagmus |
|
|
Term
| what is the symptoms and cause of MLF syndrome |
|
Definition
medial rectus paresis in lateral gaze, visual confusion, ocsillopsia, diplopia, reading fatuge, loss of steriogenesis, horizontal nystagmus in abducting eye
convergence is fine
MLF lesion in tegmentum of pons and midbrain, demyelinated plaque |
|
|
Term
| what is the cause, symptoms, treatment, and test for acoustic schwannoma |
|
Definition
benign myelin forming tumor in auditory canal or cerebellopontine angle
tinnitis, vertigo, dead caloric reflex (labrynth)
MRI, CT
removal is treatment |
|
|
Term
| what disease occurs with acoustic schwannoma, what are the types, what do they involve |
|
Definition
neurofibrmatosis type
1. involves CN VIII, V, VII, IX, X, and spinal root
2. bilateral acoustic neuroma before 21, autosomal dominent |
|
|
Term
| explain the path of the vestibular nerve after the hair cell, what are the options after the nuclei |
|
Definition
vestibular (scapra) ganglion in anternal auditory meatus > vestibular nuclei (superior, medial, lateral, inferior)then...
inferior olivary nuclei
VPI
VPL
MLF
cerebellum (fastigual nuclei, vermis, anterior, flocndular love, uvula)
medial vestibulospinal (only from medial nuclei)
lateral vestibulospinal (only from lateral nuclei) |
|
|
Term
| when the vestibular nerve sends fibers to the inferior olivary complex what do they do |
|
Definition
| vestibular influence to caudal vermis of cerebellum |
|
|
Term
| when the vestibular nerve sends fibers to the VPI |
|
Definition
|
|
Term
| when the vestibular nerve sends fibers to the VPL |
|
Definition
| go to brain area 3A and sense head position |
|
|
Term
| when the vestibular nerve sends fibers to the MLF |
|
Definition
travel on MLF from spinal cord to rostral midbrain
function in eye position and head coordination (adducts in lateral gaze)
involved with cn iii, IV, VI nuclei and stapes |
|
|
Term
| what happens in MLF is transected |
|
Definition
| medial rectus palsy. vestibular nystagmus. convergence is fine |
|
|
Term
| where is the medial vestibulospinal tract, what is its function |
|
Definition
medial vestibular nuclei to cervical and upper thoracic
head relation to eye position |
|
|
Term
| what is the function of the lateral vestibulospinal tract |
|
Definition
| extensor tone and antigravity muscles (posture) |
|
|
Term
| what happnes in a lesion of the lateral vestibulospinal tract |
|
Definition
|
|
Term
| explain how the cerebellum areas are involved with the vestibular efferent tracts and vestibular nerve |
|
Definition
via the inferior peduncle fibers join the efferent tracts of the nuclei and control equlibrium, balance, and compensatory eye movement
they go back to the nuclei and travel CN VII back and mediate spontanous firing rate of vestibular fibers |
|
|
Term
| what forms the superolateral wall of the 3rd ventricle |
|
Definition
| thalamus, largest part of diencephalon |
|
|
Term
| where does the input from the thalamus come from |
|
Definition
| precortical senrory from all sensory systems except olfactory and cerebral cortex |
|
|
Term
| what is the output from the thalamus |
|
Definition
| cerebral cortex, basal ganglia, hypothalamus |
|
|
Term
| what are the major functions of the thalamus |
|
Definition
| sensory and motor system integration, impulses of similar function sorting, exciting, and relaying. mediation of sensation, motor, cortical arousal, learning, and memory |
|
|
Term
| what are the areas of the thalamus |
|
Definition
| anterior, mediodorsal, intralaminar, ventral, dorsal (lateral) |
|
|
Term
| what is the input, output, and function of the anterior nuclei of the thalamus |
|
Definition
mamillary nucleus > mammillothalamic tract > nuclei
hippocampus > fornix > nuclei
output: to cingulate gyrus
function: pape's circut of emotion for the limbic syste, |
|
|
Term
| what is the location, input, and function of the mediodorsal nuclei |
|
Definition
location: connected to prefrontal cortex and intralaminar nuclei
input: amyglaoid, temopral neocortex, substantia niagra
function: expression of affect, emotion, behavior |
|
|
Term
| wernicke-korsakoff: symptom, cause |
|
Definition
mediodorsal nuclei destruction
thiamine (B1) deficiency
memory loss |
|
|
Term
| what are the intralaminar nuclei, what are their input |
|
Definition
input: reticular formation, ascending reticular system, other thalamic nuclei
centromedian, parafasicular |
|
|
Term
| what is the input and output of the centromedian nuclei |
|
Definition
input: reticular formation, ascending reticular system, other thalamic nuclei AND globus pallidus
output: motor cortex area 4, stratium (caudate nuclei and putamen), neocortex |
|
|
Term
| what is the output of the parafasicular nuclei |
|
Definition
| stratum, supplementary motor cortex area 6 |
|
|
Term
| what are the ventral nuclei, what are their input |
|
Definition
ventral anterior
ventral lateral
ventral posterior(ventral posteromedial
ventral posteroinferior) |
|
|
Term
| what is the input and output of the ventral anterior nuclei and their functions |
|
Definition
input
globus pallidus > thalamic and lenticular fasiculi (H1 and 2) > nuclei
and
substantia niagra > ventral anterior > motor functions
output
prefrontal cortex
premotor cortex area 6 |
|
|
Term
| what is the input for the ventral lateral nuclei and their functions |
|
Definition
globus pallidus > thalamic lenticular fasiculi (H1 and 2)> nuclei
substantia niagra > nuclei
cerebellum dentate nuclei > ventral lateral > influences somatic motor mechanisms |
|
|
Term
| what is the output and function of the ventral lateral nuclei |
|
Definition
output: motor cortex 4, supplemtary motor cortex 6, striatal motor system (somatic motor mechanisms)
function
influence somatic motor mechanisms |
|
|
Term
| what happens if you destory the ventral lateral nuclei |
|
Definition
| sterotactic destruction reduces parkinsons |
|
|
Term
| what is the input to the ventral posterior nuclei |
|
Definition
| input: GSA (pain and temp) and SVA (taste) information |
|
|
Term
| what is the input to the ventral posterolateral nuclei |
|
Definition
| GSA (pain and temp) and SVA (taste) information, spinothalamic tracts, medial laminiscus |
|
|
Term
| what is the output of the ventral posterolateral nuclei |
|
Definition
|
|
Term
| what happens in a lesion of the ventral posterolateral nuclei |
|
Definition
contralateral loss of pain and temp
tactile discrimination in trunk and extremities |
|
|
Term
| what is the input to the ventral posteromedial nuclei |
|
Definition
trigeminothalamic tract
taste info from the solitary and parabrachial nuclri |
|
|
Term
| what is the output of the ventral posteromedial nuclei |
|
Definition
|
|
Term
| what happens in a lesion of the ventral posteromedial nuclei |
|
Definition
contralateral loss of pain, temp, and tactile discrminiation of the head
ipsilateral loss of taste |
|
|
Term
| what is the input to the ventral posteroinferior nuclei |
|
Definition
| vestibulothalamic fibers from vestibular nuclei |
|
|
Term
| what is the outpur of the ventral posteroinferior nuclei |
|
Definition
| vestibular area of the somatosensory cortex |
|
|
Term
| what nuclei are in the dorsal (lateral from soltesz lecture) of the thalamus |
|
Definition
lateral dorsal
lateral posterior
pulvinar
lateral geniculate
medial geniculate |
|
|
Term
| what is the location, input, and output of the lateral dorsal nuclei |
|
Definition
posterior extension of anterior nuclear complex
input mammillothalamic tract
output: cingulate gyrus (part of limbic) |
|
|
Term
| what is the location, input, and output of the lateral posteriornuclei |
|
Definition
between lateral dorsal and pulvinar
recoprical connection with superior parietal cortex 5 and 7 |
|
|
Term
| what is the input of the pulvinar nuclei |
|
Definition
association cortex of occipital, parietal, and posterior temporal lobes
lateral and medial geniculate
superior colliculus |
|
|
Term
| what is the output and function of the pulvinar nuclei |
|
Definition
association cortex of occipital, parietal, and posterior temporal lobes
integrate visual, audiroty, and somatosensory information |
|
|
Term
| what happens in a lesion of the pulvinar nuclei |
|
Definition
| if on dominate side: sensory aphasia, neglect, attention deficit |
|
|
Term
| what is the input of the lateral geniculate |
|
Definition
| retinal input via optic tract |
|
|
Term
| what is the output of the lateral geniculate and function |
|
Definition
optic radiation > primary visual cortex (area 17 on lingus gyrus and coneus)
visual relay nuclei |
|
|
Term
| what is the input, output, and function of the medial geniculate |
|
Definition
input: audiroty input via brachium of inferior colliculus
output: primary auditory cortex (41 and 42)
function: auditory relay nuclei |
|
|
Term
| what supplies blood to the thalamus |
|
Definition
posterior communicating artery > aterior thalamoperforating arteries
posterior cerebral artery > posterior choridal and posterior thalamopherforating arteries
anterior choridal |
|
|
Term
| what is the internal capsule made of, where is it located |
|
Definition
| white matter, sperating caudate nuclei and thalamus from lentiform nuclei laterally |
|
|
Term
| where is the anterior limb of the internal capsule located |
|
Definition
| between caudate nuclei and lentiform nuclei (globus pallidus and putamen) |
|
|
Term
| what are the contents of the anterior limb of the internal capsule. where do these fibers project to and from |
|
Definition
frontopontine (corticofugal fibers): frontal cortex to pons
thalamocortical fibers: medial anterior nuclei to frontal lobes |
|
|
Term
| what fibers are severed in prefrontal lobotomy |
|
Definition
| thalamocortical fibers of the anterior limb of the internal capsule |
|
|
Term
| what supplies blood to the anterior limb of the internal capsule |
|
Definition
anterior cerebral artery inferiorly > medial striate and recurrent artery of heubner
middle cerebral artery superiorly > lateral striate > lentculostriate branches |
|
|
Term
| what does the genu of the internal capsule contain |
|
Definition
|
|
Term
| what supplies blood to the genu of the internal capsule |
|
Definition
internal carotid branches
anterior coroidal > pallidal branches |
|
|
Term
| where is the posterior limb of the internal capsule located |
|
Definition
| between talamus and lentiform nuclei |
|
|
Term
| what are the contents of the posterior limb of the internal capsule |
|
Definition
sensory radiations (pain, temp, touch)
corticospinal fibers
visual and auditory radiations |
|
|
Term
| what supplies blood to the posterior limb of the internal lcapsule |
|
Definition
anterior choridal branches
medial cerebral > lenticular branches |
|
|
Term
| why would you ligate the anterior choridal artery branches, what are the effects |
|
Definition
in parkinsons patients
causes infrarction of corticospinal tract and destories inner globus pallidus causing contralateral hemiparesis and reduction of rigidity |
|
|
Term
| what is a common cause of infarction of the internal capsule |
|
Definition
| occlusion of the lenticulostriate branches of the middle cerebral artery |
|
|
Term
| what are the symptoms of infarction of the internal capsule |
|
Definition
| contralateral tactile hypoesthesia, anesthesia, hemiparesis (with babinski's sign), lower facial weakness, homonymous hemianopia |
|
|
Term
| thalamic syndrome: AKA, causes |
|
Definition
dejerine and roussy
thalamic stroke, damage causes miscommunication between afferent pathway of cortex
usually occlusion of a posterior thalamo-perforating artery |
|
|
Term
| thalamic syndrome: symptoms |
|
Definition
changes in how a patient feels
contralateral hemiparesis and hemianesthesia
elevated pain threashold
spontaneous, agonizing, burning pain (hyperpathia, dyaesthesia, allodynia)
thalamic hand |
|
|
Term
|
Definition
athetotic posturing of hand
wrist pronated and flexed
metacarpals flexes
proximal extended |
|
|
Term
| what are the zones of the hypothalamus and their sub divisions |
|
Definition
pre-optic: medial and lateral nuclei
lateral
medial: supraoptic, tuberal, mamillary, periventricular |
|
|
Term
| what are the functions / fiber outputs of the lateral pre-optic nuclei |
|
Definition
ventrolateral area sends fibers out for sleep
sends fibers to ventral palluadum (globus pallidus) for movement |
|
|
Term
| what are the outputs and functions of the medial pre-optic nuclei |
|
Definition
tuberoinfundibular tract: releases GnRH into hypophyseal portal system to cause anterior pituitary to release LH and FSH
fibers for eating and movement behaviors |
|
|
Term
| what are some differences in the pre-optic area in different people |
|
Definition
| larger in males because females hormones cycle, males stay constant at the high |
|
|
Term
| what are the nuclei and major axon bundles of the lateral zone of the hypothalamus |
|
Definition
lateral hypothalamic nuclei
tuberal nuclei
axons from the medial forebrain going to septal nuclei and reticular formation
axons from lateral hypothalamic area |
|
|
Term
| what are the outputs of the lateral hypothalamic nuclei |
|
Definition
has fibers that release histamine to the cerebellum for motor functions
controls wake state
has multipolar neurons |
|
|
Term
| what are the nuclei of the supraoptic area |
|
Definition
| supraoptic, paraventricular, suprachiasmatic, anterior |
|
|
Term
| what are the nuclei of the tuberal area, what are their functions |
|
Definition
ventromedial: satiety
dorsal medial: emotional balance
arcuate: releasing hormones sent to tuberoinfundibular tract> hypophyseal portal system > anterior pituitary |
|
|
Term
| what are the nuclei of the mamillary area, what is the general function |
|
Definition
mamillary nuclri: medial, inferior, lateral
posterior hypothalamic nuclei
function: trun short term into long term memory |
|
|
Term
| what is the function and output of the supraoptic and prarventricular nuclei |
|
Definition
| output is hypothalamic-hypophyseal tract to the posterior pituitary that releases ozytocin and ADH |
|
|
Term
| what happens in a lesion of the supraoptic and paraventricular nuclei |
|
Definition
| neurogenic diabetes insipidus |
|
|
Term
| what is the input, output, and function of the suprachiasmatic nuclei |
|
Definition
input: retino-hypothalamic tract
output: fibers for circadian rhythm |
|
|
Term
| what is the function of the anterior nuclei of the supraoptic area |
|
Definition
| maintain body temp by sensing heat with thermosensitive neurons and decreasing heat |
|
|
Term
| what happens in a lesion of the anterior nuclei of the supraoptic area |
|
Definition
|
|
Term
| what is the input, output, and function of the medial mamillary nuclei |
|
Definition
inut: posterior comissural fornix
output: mamillothalamic tract to the anterior nuclei of the thalamus (limbic function) |
|
|
Term
| what is the output and function of the lateral memillary nuclei |
|
Definition
| mamillary peduncle > reticular formation of the midbrain |
|
|
Term
| what is the function of the posterior hypothalamic nuclei |
|
Definition
merges with PAG to control emotion, cardiovascular, analgesic
decreased blood temp > vasoconstriction and shivering > heat |
|
|
Term
| what happens in a lesion of the posterior hypothalamic nuclei |
|
Definition
| can't regulate heat, hot or cold |
|
|
Term
| what is the function of the periventicular nuclei, what is the outpt |
|
Definition
| sends fibers to the tuberoinfindbular tract to release releasing and inhibitory hormones |
|
|
Term
| functions of the diencephalon |
|
Definition
| controls visceral function (ANS), controls endocrine system, maintains homeostasis (water, electrolyte, food, temp, BP, sleep, circadian, metabolism) |
|
|
Term
|
Definition
| region around mamillary bodies, optic chiasm, and first part of optic tract |
|
|
Term
| where does the pituitary stalk emerge, what is in it |
|
Definition
| comes from median eminence, has neurohypophysis in it |
|
|
Term
| what does the lamina terminalis seperate |
|
Definition
| hypothalamis and septal nuclei |
|
|
Term
| what does the form of the hypothalamus create |
|
Definition
| 3rd venricle, place for mamillary bodies to sit (ventrally) |
|
|
Term
| describe the embryologic origin of the pre-optic area |
|
Definition
| derived from telencephalon but function is hypothalamus |
|
|
Term
| explain where each zone of the hypothalamus is located |
|
Definition
preoptic: medial to lamina terminalis, continous with forebrain
paraventricular: beneath ependymal cells of 3rd ventricle
medial: lateral to periventicular |
|
|
Term
| what divies medial and lateral zone of the hypothalamus |
|
Definition
| posterior comissure fornix to mammillothalamic tract |
|
|
Term
| what is a circumventricular organ, what makes it different than other organs |
|
Definition
atypical brain tissue located in walls of 3rd and 4th ventricle
no BBB, chemoreceptor and neurosecretatory function |
|
|
Term
| what does OVLT stand for, what is it, where is it, what is its function |
|
Definition
organum vasculosum laminae terminalis
a circumventricular organ in the laminae terminalis
fever and regulation of Na metabolism (cravings) |
|
|
Term
| explain how a fever is created |
|
Definition
| pyrogens from bacterial decomp > blood > permeable vessels of circumventricular organ in pre-optic area > OVLT > dendrites > inhibits mechanisms that cause loss of heat |
|
|
Term
| what are the symptoms of a hippocampal lesion |
|
Definition
memory impairment (mostly recent), cannot turn short term into long term
if circut of papez is damaged memory stays in tact (early memories are in the cortex)
interruption of limbic system |
|
|
Term
| what lesion has simillar symptoms of a hippocampal lesion |
|
Definition
|
|
Term
| explain the symptoms and cause of korsakoff's psychosis |
|
Definition
lesion in diencephalon commonly caused by alcoholism (also in thalamus and mamillary bodies)
compensate for short term memory loss by interting remembered events into stories |
|
|
Term
| what is the nervus terminalis, what is its function |
|
Definition
| nerve tha projecs into pre-optic and paraventricular areas that makes GnRH to stimulate gonadotrophin secretion to control ovaries and testis |
|
|
Term
| what is the embryology of the nervus terminalis |
|
Definition
| olfactory placode > olfactory epithelium with glial cells and olfactory nerve and nervus terminalis |
|
|
Term
| what is kallman syndrome: cause, symptoms |
|
Definition
| olfactory placode development > defective > defective nervus terminalis > no Gnrh > ansomia and non-functional gonads |
|
|
Term
| explain the role of the tuberomamillary nucleus in sleep |
|
Definition
histaminergic neuron axons go to reticular formation, thalamus, and cortex and are inactive during sleep
form part of sleep arousal system |
|
|
Term
| explain the role of the pre-optic area in sleep |
|
Definition
neurons that make GABA and glanin peptide are active in sleep
axons also go to tuberomamillary nuclei and inhibit histaminergic neurons
axons also go to reticular formation and inhibit cholinergic neurons |
|
|
