Exam 1 - Week 3 Flashcards
1
Q
3 major basal ganglia nuclei
A
caudate nucleus, putamen, globus pallidus
2
Q
striatum components
A
caudate nucleus, putamen
3
Q
lentiform nuclei components
A
putamen and globus pallidus
4
Q
nucleus accumbens function
A
reward pathways
5
Q
general function of basal ganglia
A
modulates and supervises outflow of descending motor pathways from the primary motor cortex via its actions on the thalamus
6
Q
do the basal ganglia have any direct connection with spinal cord?
A
no
7
Q
disruption of basal ganglia results in ______ but not _____
A
hyperkinetic or hypokinetic movement disorders, paralysis
8
Q
non-movement functions of basal ganglia
A
cognition, mood, reward
9
Q
where do basal ganglia receive input from
A
premotor and supplementary motor cortex areas involved in planning movement
10
Q
basal ganglia output travels to
A
cerebral motor cortex via the thalamus
11
Q
major neurotransmitters involved in basal ganglia
A
glutamate, GABA, dopamine, acetylcholine
12
Q
Ach role in basal ganglia
A
interneurons
13
Q
difference between D1 and D2 receptors
A
D1 promotes excitability of postsynaptic cell, D2 depresses excitability of postsynaptic cell
14
Q
main difference in function between direct and indirect pathways
A
direct pathway facilitates movement, indirect pathway inhibits movement
15
Q
what happens if direct pathway has too much activity
A
unwanted movements
16
Q
what happens if the indirect pathway is too active
A
more difficult to initiate movement and movement is slow
17
Q
what receptor do neurons of direct pathway express
A
D1
18
Q
what receptor do neurons of indirect pathway express
A
D2
19
Q
why is the indirect pathway called indirect
A
because it passes through subthalamic nucleus
20
Q
essential tremor presentation
A
Tremor during voluntary movement
21
Q
essential tremor diagnosis
A
Clinical
22
Q
Huntington’s presentation
A
progressive dementia, chorea
23
Q
Huntington’s diagnosis
A
family history, genetic testing
24
Q
Parkinson’s ssx
A
Progressive hypokinetic movement disorder with resting tremor, bradykinesia, cogwheel rigidity, postural instability
25
Parkinson's tx: surgical
deep brain stimulation to suppress the indirect pathway
26
Ballismus treatment
dopamine-blocking agents, GABA mimetics, surgery (deep brain stimulation or ventral thalamotomy)
27
Parkinson's pathophys
Mostly idiopathic progressive degeneration of dopaminergic neurons within the substantia nigra pars compacta leading to depletion of dopamine within the striatum
28
most important Parkinson's risk factor
age
29
Parkinson's treatment: pharmacological
primarily levodopa/carbidopa
30
what is ballismus
uncontrollable, violent flinging/ballistic movements of upper or lower extremity, contralateral to the subthalamic nucleus lesion
31
most common cause of ballism
vascular infarct in subthalamic nucleus
32
Huntington's pathophys
hyperkinetic movement disorder due to severe degeneration of GABA-ergic neurons within caudate-putamen leading to inability to filter unwanted movements
33
Huntington's genetics
Autosomal dominant trinucleotide repeats (CAG repeats) in Huntingtin gene on chromosome 4
34
Huntington's imaging findings
hydrocephalus ex vacuo, gyral atrophy of frontal and temporal lobes
35
thalamus function
receive and relay all sensory information except olfactor
36
which thalamic nucleus do the spinothalamic and DCML pathways use
ventral posterolateral
37
thalamic nucleus for sensory to face and taste
ventral posteromedial
38
thalamic nucleus for vision
lateral geniculate
39
thalamic nucleus for hearing
medial geniculate
40
thalamic nucleus for motor
ventral anterior and lateral
41
afferents for ventral anterior and lateral thalamic nucleus
basal ganglia and cerebellum
42
most common cause of thalamic damage
lacunar stroke
43
key symptoms of thalamic lesion
contralateral sensory loss in face, arms, legs in all sensory modalities resolving to become chronic pain with normal sensory exam
44
Hypothalamus function
maintains homeostasis by regulating TAP HATS
45
TAP HATS
Thirst/water balance, anterior pituitary, posterior pituitary, hunger, autonomic nervous system, temperature, sexual urges
46
Limbic system function
more primitive part of brain that has role in basic emotions (anger, fear) and regulates fight/flight behaviors
47
Connections of limbic system
hypothalamus and olfactory system
48
limbic system specific functions
homeostasis, olfaction, memory formation, emotional expression, reward pathway (depression/substance abuse)
49
2 circuits of limbic system
medial limbic circuit (Papez), limbic loop
50
medial limbic circuit function and components
formation/expression of memories; hippocampus, fornix, mamillary bodies, anterior nucleus of thalamus
51
Limbic loop function and components
Reward pathway; amygdala, nucleus accumbens, mediodorsal nucleus of thalamus
52
Components of medial limbic circuit
He-man ate a cat
53
he-man ate a cat
hippocampus, mamillary body (hypothalamus), anterior thalamic nuclei (thalamus), cingulate gyrus (limbic)
54
What is Wernicke-Korsakoff
lack of thiamine in brain leads to atrophy of mamillary bodies and damage to thalamic nuclei
55
Wernicke-Korsakoff ssx
anterograde and retrograde amnesia, confabulation, lack of insight/apathy, personality changes
56
what is triad of Wernicke
reversible with thiamine: visual disturbances, gait ataxia, confusion
57
bilateral hippocampal damage leads to
severe anterograde amnesia with absent/mild retrograde amnesia
58
major function of cerebellum
modulates intensity of cortical/brainstem influence on lower motor neurons
59
3 lobes of cerebellar cortex
anterior, posterior, flocculonodular
60
how is the cerebellum connected to the brainstem
3 pairs of cerebellar peduncles
61
what are the 3 cerebellar peduncles and their contents
superior: efferent fibers. Middle: afferent fibers. Inferior: efferent and afferent fibers
62
what are the cerebellar arteries and what are they branches of
superior (basilar), anterior inferior (basilar), posterior inferior (vertebral)
63
areas supplied by SCA
superior surface of cerebellar hemispheres, superior vermis, dentate nucleus, parts of midbrain
64
areas supplied by AICA
middle cerebellar peduncle, lower lateral pons, anteroinferior surface of cerebellum, flocculus, choroid plexus of lateral ventricle
65
what is labyrinthine artery
branch of AICA that supplies labyrinth, cochlea, facial nerve, vestibulocochlear nerve
66
areas supplied by PICA
posteroinferior cerebellar hemispheres, cerebellar tonsils, nucleus gracilis, inferior vermis, lower medulla, inferior cerebellar peduncles
67
what are the major output neurons of the cerebellum called and what do they do
Purkinje neurons; release GABA onto deep cerebellar nucleii neurons to regulate their activity
68
what are the 3 regions of cerebellum
spinocerebellum, vestibulocerebellum, cerebrocerebellum
69
what is the spinocerebellu,
consists of vermis and paravermal zones and receives information about unconscious proprioceptive movement and helps control movement for locomotion, posture, balance
70
what is the vestibulocerebellum
flocculonodular lobe that receives info from the vestibular apparatus and regulates vestibulo-ocular reflex and extensor lower motor neurons to control equilibrium and balance
71
what is the cerebrocerebellum
lateral cerebellar hemispheres with afferents from cortex and controls multi-joint movements of limbs and learning/storage of sequential skilled movements
72
definition of ataxia
loss of motor coordination in voluntary movements
73
signs of vestibulocerebellum damage
truncal ataxia, nystagmus, oculomotor disturbances, balance problems
74
signs of spinocerebellum damage
gait and lower limb ataxia
75
signs of cerebrocerebellum damage
dysmetria, intention tremor, cannot perform rapid alternating movements, scanning speech, cognitive alterations, fragmentation of movement
76
L-dopa MOA
dopamine precursor that increases dopamine production
77
carbidopa MOA
peripheral dopa decarboxylase inhibitor that increases L-dopa bioavailability
78
entacapone MOA
peripheral COMT inhibitor
79
Selegiline MOA
central MAO B inhibitor that decreases dopamine degradation
80
Ropinirole MOA
dopamine agonist (stimulates postsynaptic DA receptors)
81
trihexyphenidyl MOA
muscarinic antagonist that curbs excess cholinergic activity
82
amantadine MOA
antiviral agent that mildly increases dopamine release, has anticholinergic and NMDA antagonist properies
83
levodopa/carbidopa aka
Sinemet
84
sinemet side effects
nausea, tachycardia/afib, psychosis, dyskinesia
85
Ropinirole side effects
nausea, orthostatic hypotension, hallucinations
86
advantages and disadvantages of dopamine receptor agonists for PD
do not depend on dopaminergic neuron function, longer duration of action, delay need for L-dopa. Not as effective as L-dopa for alleviating symptoms
87
trihexyphenidyl use in PD
used to treat tremor with little effect on bradykinesia
88
trihexyphenidyl side effects
anticholinergic effects
89
amantadine side effects
dizziness, lethargy, sleep disturbances
90
amantadine uses for PD
not monotherapy, generally given in later stages as add-on
91
cholinesterase inhibitors for alzheimers
donezepil, rivastigmine, galantamine
92
NMDA antagonist for Alzheimers
memantine
93
ALS drug
riluzole
94
Huntiungtons drug
tetrabenazine (VMAT2 inhibitor)
95
Rilozole MOA
decrease glutamate excitotoxicity
96
MAO-B inhibitors for parkinsons
Selegiline, rasageline
97
dopamine receptor agonists for Parkinsons
Ropinirole, pramipexole
98
anticholinergics for parkinsons
benztropine, trihexyphenidyl
99
entacapone side effects
dyskinesia, nausea, somnolence, orthostatic hypotension
100
MAO-B inhibitors uses for PD
can be monotherapy or prescribed with sinemet to reduce dose of sinemet and prolong its duration of effectiveness to decrease "wearing off" phenomenon
101
Amantadine side effects
hallucinations
102
cholinesterase inhibitors side effects
GI distress, muscle cramping, abnormal dreams
103
cholinesterase inhibitors uses in Alzheimers
early stages to delay progression by 6-12 months
104
Memantine uses in Alzheimers
adjunct or alternative to cholinesterase inhibitor in later stages
105
memantine side effects
headache, dizziness
106
Rilozule side effects
nausea, diarrhea
107
Riluzole indications for ALS
extend survival by 2-3 months by decreasing glutamate toxicity
108
tetrabenazine MOA
VMAT2 inhibitor that causes presynaptic depletion of catecholamines
109
tetrabenazine side effects
hypotension and depression
110
which parts of basal ganglia are involved in motor function
subthalamic nucleus and substantia nigra
111
basal ganglia are part of which loop
subcortical
112
basal ganglia have no direct connections with ____
spinal cord or cerebellum
113
Describe the direct pathway
motor cortex stimulates striatum with glutamate, which inhibits the globus pallidus interna so that the thalamus can stimulate the motor cortex with glutamate
114
describe the indirect pathway
the motor cortex stimulates the striatum with glutamate which then inhibits the globus pallidus
115
where is the horizontal gaze center and what is it called
the pons, the PPRF
116
what is each PPRF controlled by
the contralateral frontal eye field
117
where is the vertical gaze center located
dorsal midbrain
118
function of vestibulo ocular reflex
keeps eyes on fixed target when head rotates by moving the eyes in the opposite direction
119
what mediates the vestibulo ocular reflex
the vestibular apparatus in the inner ear
120
describe the vestibulo ocular reflex
sensory information about head position is transmitted from sensory hair cells in the inner ear to the vestibular nuclei within the brainstem, which then drives the ocular motor nuclei of CN III, IV, VI
121
cause of internuclear ophthalmoplegia
lesion of MLF, classically due to MS or pontine infarct
122
what is the convention for which side the INO is on
the same side of the lesion in the MLF
123
left INO ssx
weakened adduction of left medial rectus on attempted gaze to the right, nystagmus in right eye
124
what is true of convergence in INO
it is spared
125
frontal eye field lesion/PPRF ssx
contralateral PPRF dysfunction causes inability to gaze in that direction
126
left FEF/PPRF lesion ssx
inability to gaze to the right
127
lesion of left medial longitudinal fasciculus ssx
left INO
128
FEF from stroke ssx
gaze preference toward side of lesion unless the stroke is in the PPRF, in which case the eyes will look toward the side of body weakness
129
gaze preference toward side of body weakness signifies
stroke in PPRF or CN VI damage
130
common theme of neurodegenerative disorders
protein aggregates accumulate in neurons, which cause inflammation and are toxic to neurons
131
initial ssx of alzheimers
short term memory loss due to inital stages of disease confined to medial temporal lobe
132
mild alzheimers characteristics
disease spreads to lateral temporal and parietal lobes, ssx poor object recognition/direction sense
133
characteristics of moderate alzheimers
disease spreads to frontal lobe, ssx of poor judgment, impulsivity, short attention
134
characteristics of severe alzheimers
disease spreads to occipital lobe, ssx of hallucinations, mutism
135
alzheimers pathophys
degeneration of cholinergic neurons in nucleus basalis of Meynert with beta amyloid deposition, neurofibrillary tangles and tau plaques
136
frontotemporal dementia aka
Pick's disease
137
pick's disease ssx
progressive deterioration of language and changes in personality such as disinhibition, hyperorality, apathy, loss of empathy, compulsive behaviors. These precede memory disturbance and occur at younger ages
138
Lewy body dementia presentation
fluctuating attention and cognition and visual hallucinations with later manifestations of parkinsonian movement problems
139
how many CAG repeats do Huntington's patients have
40-50
140
a high number of CAG repeats is associated with
early onset and more rapidly progressive Huntingtons
141
vascular dementia ssx
early: cognitive deficits in reasoning and judgment. Later stages, problems with memory
142
MRI findings in vascular dementia
diffuse white matter changes in at least 25% of white matter
143
CJD ssx
rapidly progressive dementia with ataxia and startle myoclonus
144
what is major afferent pathway from spine into cerebellum
inferior cerebellar peduncle
145
what does the inferior cerebellar peduncle carry
ipsilateral spinal cord info on proprioception
146
what does middle cerebellar peduncle carry
fibers from contralateral pons
147
major pathway out of cerebellum
superior cerebellar peduncle that travel from deep nuclei to red nucleus and thalamus to modyfy motor activity
148
lesions of cerebellum cause ______ symptoms
ipsilateral
149
lateral cerebellum lesions ssx
affect extremities: direction/force/speed of movements: dysmetria, intention tremor, falls toward injured side
150
medial cerebellar lesions ssx
truncal ataxia, nystagmus, vertigo
151
cerebellum anterior lobe functions
maintains coordination of limb movements, strongly connected with spinal cord
152
signs of anterior lobe of cerebellum damage
gait ataxia, lower limb ataxia
153
causes of anterior lobe of cerebellum damage
B1 deficiency, B12 deficiency
154
posterior lobe of cerebellum functions
multi-joint movement of limbs, learning and storage of sequential components of skilled movements
155
causes of lateral cerebellar hemispheres damage
infarction, hemorrhage, tumor, MS
156
flocculonodular lobe functions
coordination of muscles associated with equilibrium and eye movements
157
flocculonodular lobe damage ssx
truncal ataxia, nystagmus, oculomotor disturbances
158
causes of flocculonodular lobe damage
4th ventricle tumor, MS, CP
159
vestibulospinal tract function
facilitates extensor activity, inhibitor function of descending corticobulbar tract
160
genetic connection for alzheimer's dementia
APOE4
