NB3 EXAM 2 Flashcards
The fibers of the lateral olfactory tract termine where
olfactory tubercle, anterior perforated substance, entorhinal cortex and pyriform cortex
what is the only system that projects directly to the cortex without going to thalamus first
olfactory
which system is responsible for the identification of odors
orbitofrontal cortex
which system is responsible for the emotional response to odors
hypothalamus, entorhinal cortex, hippocampus and hypothalmus
hyposomia is
rediced ability to detect odors
anosmia is
complete inability to detect odors
parosmia
change in normal perception of odors
phantosmia:
sensation of an odor that is not there
what taste buds are located on the front of the tongue, side of tongue and back of tongue
fungiform, foliate, and circumvallate
in taste, once VII, IX, and X neurons get to the NTS, where to they project?
to the VMP of the thalmus and then to the insular and frontal cortex
what higher brain centers project to the NTS for taste manipulation
amygdal and hypothalamus. the insular and frontal cortex indirectly
defect in LCA
the retinal pigment epithelium fails to phagocytose the shed outer segments of the photoreceptor cells.
papilladema
swelling of the optic nerve head, correlated with intracranial pressure increases
what causes retinitis pigmentosa
Loss of Rod photoreceptors; mutations in rhodopsin and other components of the g-protein cascade cause retinitis pigmentosa. You will see thin vessels, pale retina, and protrusion of RPE cells into the retina itself
what is usually the first complaint for people with retinitis pigmentosa?
loss of night vision
Macular Degeneration
loss of cone photoreceptors and loss of foveal vision since the fovea is made solely of cones
the Cone “on” pathway depends on
MGLUR6
the “off” cone pathway depends on
ionotropic glutamate receptor
why do people with metastatic melanoma become night blind?
because they are producing atibodies to the trp channel, so the channel cannot open and the cell cannot depolarize to sense light.
congenital stationary night blindness
mutations in MGLUR6
lesion in the left occipital lobe –>
a problem with the PCA. This leads to pure alexia (inability to read) without agraphia .
dyslexia is involved with what part of he brain
palum temporale
in terms of language what does the right hemisphere do
intonation and language used in social context, like sarcasm
sensory neglet or asomatognosia comes from
damage to the superior part of the parietal love
tectospinal tract does
originated in the superior collicuus and turns gaze to an area of interest. involves only muscles inntervated in the upper cord
damage to the medial pathways
causes changes in muscle tone and may include defecits in maintaing balance
4 projections of motor nucelu
red nucleus
reticular formation
superior colliculus
vestibular nuceli
horizantal eye movements are related to
PPRF (Pons)
Vertical eye movements are related to
Mesencephalic reticular formation, MRF (midbrain)
what 4 things project to the PPRF
cortical frontal eye fields, basal ganglia, cerebellum, superior colliculus
most important structure in initiating saccadic eye moveents?
superior colliculus
retinal input goes to the ___ layer of the superior colliculus
superior layer
the deep layer of the superior colloculus contins
motor innervtion
is the sensory map of the superficial layer of the superior colliculus in register with the motor map that generates the appropriate moveents?
yes
where do frontal eye fields project to initiate eye movement?
both to the brainstem directly to initiate movement and to the deep layers of the superior colliculus
a lesion to both the frontal eye fields and the superior colliculus results in
no saccades
a lesion to the frontal eye fields results in
the ability to make saccades to visual targets without the ability to to make saccades to remembered targets
a lesion to the superior coliculus results in
ability to make saccades to remembered targets but not to visual targets
what area is involved in controlling smooth pursuits
middle temporal area
if you see nystagmus think
lesion to the vestibular nerve
striatum =
caudate and putamen
Lentiform =
putamen and the globus pallidus
hemiballismus is ___ and results from ___
It is increase in movement due to damage of the subthalamic nucleus
huntington’s is a problem of the
striatal neurons of the indirect pathway
dopamine is ____ to striatal neurons of the indirect pathway
inhibitory to
dopamine is _____ to the striatal neurons of the direct pathway
excitatory
indicrect pathway will ___ movement
decrease
direct pathway will ___movement
increase
major function of vestibulocerebellar pthway
balance and eye movements
major function of spinocerebellar pthway
motor execution, regulate tone, posture and locomotion
major function of cerebrocerbellum pthway
coordination and planning of voluntary movement
inputs to the vestibulocerebellar pathway
vestibular nerve, vestibular nucelei, inferior olive
sources of the outputs of the vestibulocerebellar pathway
perkinje cells and fastigial nucleus
targets of outputs of the vestibulocerebellar pathway
vestibular nuceli, reticular formation, VL of the thalamus
what part of the motor system does the vestibulocerebellar target?
UMN of medial pathways
Major signs of damage to the vestibulocerebellar pathway
stagering gait or nystagmus
inputs of the spinocerebellar pathway
all 4 of the spinocerebellar tracts and the inferior olive
sources of outputs of the spinocerebellar pathway
fastigial nucleus and interposed nucleus
targets of outputs of the spinocerebellar pathway
vestibular nuceli, reticular formation, VL of thalamus, red nucelus
part of motor system targeted by the spinocerebellar pathway
UMN of medial and lateral pathways
signs of damage to the spinocerebellar pathway
intention tremor
inputs of the cerebrocerebellar pathway
pontine nuclei (relaying info from the sensory and motor cerebral cortex) and inferior olive
sources of outputs of the cerebrocerebellar pathway
dentate nucleus
targets of outputs of the cerebrocerebellar pathway
VL of the thalamus and the red nucleus
part of motor system targeted by the cerebrocerebellar pathway
motor cortex
if you see gait ataxia and nystagmus and decide tht you have a problem with the verims and flocculonodular lobe aka vestibulocerebellar, what arteries may be involved
AICA - flocculus
PICA - vermis
SCA - rostral vermis
If you see a patient with incoordination of the limbs with decomposition of movement and you believe tht the paravermal and lateral hemispheres may be damaged, what arteres do youthink?
PICA - caudal portions of lateral hemispheres
SCA - rostral portions of lateral hemispheres
patellar reflex level
L4
achilles reflex level
S1
what are the locations and relevant pathways ofthe five UMN
1- reticular formation: medial and lateral reticulospinal
2-vestibular nuceli - medial and lateral vestibulospinal tracts
3-superior colliculus- tectospinal
4- rednucleus -rubrospinal
5-motor cortex - corticospinal and corticobulbar tracts
describe the pathway of the medial vestibulospinal pathway
utricle and saccule –> medial vestibular nucelus –> descending MLF -> cervical spinal cord for neck movements and postural movements to stabalize head
describe the pathway of the lateral vestibulospinal pathway
utricle, saccule and cerebellumm –> lateral vestibular nucelus –> ipsilateral projections to the spinal cord
what are the lateal pathways used for?
to control the limbs
which pthways are consdered lateral pathways
corticospinal and rubrospinal
path of rubrospinal tract?
originates in the red nucleus, crossesmidline and descends laterally
the medial pathways are the ___ and are important for maintaing posture and balance
vestibulospinal, tectospinal and reticulopsinal
tectospinal originates
originates in the superior colliculus
the tectospinal is responsible for
turning gaze to an area of interst
where do the medial and lateral reticulospinal trct originate
medial in the pons
lateral in the medulla
what are the reticulospinal trats important for
influence on muscle tone
what is in the inferior cerebellar peduncle?
spinal cerebellar tracts heading to cerebelum
what is in the middle cerebellar peduncle?
neurons from the cortex that travel via the pontine nuclei
what is in the superior cerebellar peduncle?
mostly outputs from the deep nuclei of the cerebellum to the thalamus
wernike and broca are located on which side of the brain?
the left
the sensory/ expressive language area is
Wernicke, posterior
the motor/ expressive languge area is
Broca, anterior
what connects the wernicke and broca areas
arcuate fasciculus
pathway of repeating a spoken word
primary auditory cortex –> wernicke –> Broca –> motor primary cortex –> corticobulbar
repeating a written word
eyes –> primrary visual cortex –> wernicke –> broca –> motor cortex
WADA test
uses a barbituate to determine dominant side.
brocas aphasia is
nonfluent, very simple sentences, comprehesion is preserved. right hemiparesis in the arm
(MCA)
wernicke’s aphasia
speech is fluent but they arent making any sense.No motor signs
conduction aphasia
arcuate fasciculus impaired so fluent and comprehesion is preserved but cannot repeat
a lesion of the left occipital lobe and in the splenium of the corpus callosum would be caused by _____ and would lead to _____
PCA
the connections between the unilateral language areas are severed. So you get pure alexia (inability to read) without agraphia (inaibility to write)
a lesion of the dominant angular gyrus would cause
alexia and agraphia
dyslexia is believed to be due to
a lack of assymmetry in the planum temporale
the right hemisphere contributes to language in what way?
stress, timing and intonation –> monotone and dont understand jokes
the loss of musical skills results from
infarction of the posterior part of the right superior temporal gyrus
spacial perception is processed by the
superior parietal lobule
asomatognosia is the
neglect of personal space
damage to the right (nondominant) superior parietal lobe results in
asomatognosia on the left side
prosopagnosia
inability to recognize faces
which lobe is responsible for personality
frontal lobe
two areas involved in consciousness?
1) The reticular formation: responsible for wakefulness
2) The cerebral cortex: responsible for state of awareness
type of waves when alert and awake and in REM
beta waves, 14-30 hz, high frequency, low amplitude
typeof waves when quiet waking / eyes closed
alpha waves, 8-14
type of waves in sleep stage 1 and 2
theta waves, 4-8 hz
type of waves in sleep stage 3 and 4
delta waves, .5-4 hz
what keeps the thalamus in transmission mode?
cholinergic inputs from the rostral pons and basal forbrain. pedunculopontine and laterodorsal tegmental nuclei
what keeps the thalamus in burst mode?
the reticular nucelus releasing GABA and hyperpolarizing the thalamus
charactersitics of REM sleep
loss of muscle tone, eye movements, high frequency and low amplitude waves. No regulation od body temperature, sympathetics lost,
PGO spikes are
ponto-geniculo occipital spikes, correlated with eye movements in REM sleep
PGO ON SPIKES are regulated by
nucleus reticularis pontis oralis
PGO OFF spikes are rgulated by the
serotonergic cell in the raphe nuclei of the brainstem which regulate the nucleus reticularis pontis oralis
what regulates circadian rythms
suprachiastmatic nucleus
narcoslepy is
onset of REM sleep
cataplexy is
abrupt loss of muscle tone without loss of consciousness
sleepwalking occurs during
the 1st stage 4 non-REM period
caffeine is an antagonist to
adenosine receptors (adenosine is sleep promotine)
auras preceed the onset of
focal seizures
petit mal siezures are
absence siezures which are non convulsive and found in children
Grand mal seizures
tonic - clonic -patient falls to the ground rigid followed by jerking
myoclonic siezures
brief jerking movement with both sides of body
most frequent site of epileptic focus
medial surface of the temporal lobe
smells, deja vu, fear and anxiety auras are due to
amygdala being involved in the damaged area
the two forms of memory are
declarative and nondeclrative. declarative pertains to dates and facts, non-declarative pertains to habits.
the aquisition of declarative memories is due to the
medial temporal lobe
classical conditioning is
an innate reflex assocaited with an unrelated stimulus
operant conditioning is
the probabilty of an altered behavioral response by association with reward
retrograde amnesia
loss of memory for events prior to the trauma
anterograde amnesia
inability to form new memories following brain trauma
the cell affected in Alzheimer’s disease are
Hippocampal pyramidal cells
bilateral lesions of the mammillary bodies leads to
Korsakoff syndrome
what is the structure most involved with nondeclarative memories
the striatum
what is working emory
retention od information needed to guide ingoing learning and behaviours
what structure seems to be responsible for working memory
the hippocampus
what area is responsible for problem solving using recent information to change behavior?
the prefrontal cortex
senile plaques and neurofibrillary tangles are often seen in
Alzheimer’s disease
a hall mark of alzheimer’s disease is ____ plaques
amyloid
limbic system most involved with emotion is
amygdala
what are the three nuceli of the amygdala
basolateral nuclei
corticomedial nuclei
central nucleus
wht is the fx of the basolateral nuclei
visual, auditory, gustatory and tactile afferents
fx of the corticomedial nuclei
receive olfactory afferents
fx of the central nucleus
out put of the amygldala
electrical stimulation of the amygdala priduces
fear
urbache wiethe disease
is degenerative condition assciated with calcium deposit on the amygdala. Results in inaibility to discern fear.
neuropathic pains results from a
direct injury to nerves in the PNS –> burning sensation
scale of choice?
visual analogue scale
children use what type of scale?
category scale
thermoreceptive specific cell types in the dorsal horn respond to
innicuous cooling
sensory-discriminative type of pain is
sense of the intensity, location, quality and duration of the pain
the sensory-discriminative type of pain is sensed where
in the lateral system
motivational-affective component of pain is
unpleasantness and urge to escape the unpleasantness
The motivational-affective component of pain is sensed in the
medial system
main player in initiation and modulation of descending controls of nociceptive information
Periaqueductal grey
examples of acidic antipyretics are ___ and they can be used in treating ___
apririn and NSAIDs = ibuprofen
use to treat acute and chronic pain, inflammation
examples of non-acidic antipyretics are ___ and they can be used to treat ___
acetaminophen,
used to treat acute pain and fever
naloxone is an
opioid antagonist that has a high affinity for morphine receptor sites. It reverses the effect of opioid analgesics by displacement
the reticular formation
modulates pain, muscle tone and reflexes and wakefulness
midline raphe nucelus
produces seratonin, and regulates pain, arousal, and sleep
locus cerelius are
NE projecting cells - only sourceof NE in the brain
parasaggital lateral nuceli are the only source of
ACH in the brain
anterior hypothalamus influenes
PNS
posterior hypothalamus influences
SNS
the magnocellular region of the supraoptic and paraventricular nuclei make
ADH and Oxytocin
tubuloinfundibular region of the hypothaamus
brings hormones to the posterior pituitary
the posterior nucleus of the hypothalamus ______ heat
generates
the anterior nucleus of the hypothalamus _____ heat
dissipates
the lateral nuclei of the hypothalamus generates
eating
the ventromedial nucleus of the hypothalamus ___ eating
decreases
damage to the lateral nuclei of the hypothalamus would lead to the
body wasting away
the anterolateral and the DC project to the ___ of the thalamus
VPL
the trigeminal system projects to the ___ of the thalamus
VPM
the inferior colliculus projects to the ____ for ______
inferior colliculus projects to the MGB for hearing
the superior colliculus projects to the ____ for ______
LGB for vision
VL of the thalamus
cerebellum projects to the VL then goes to the precentral gyrus and frontal cortex for motor and movement planning
the thalamus is fed by what artery
PCA
infarction of the inferolateral artery does what
thalamic syndrone, with sensory loss, ataxia and paralysis t the contralateral side
posterior commisure coordiantes
eye movements
association fibers
connect adjacent gyri
conductive aphasia
can produce speech and can follow commands but cannot repeat
the projections of corticospinals through the internal capsule, the face is anterior or posterior
anterior
