final exam (new content) Flashcards
what is the embryological origin of the thalamus?
diencephalon of prosencephalon
what is NOT processed in the thalamus?
olfaction
what are the thalamic nuclei?
lateral nuclear group, medial nuclear group, anterior nuclear group
paraventricular nuclei
separates the medial part of thalamus with ependymal cells of 3rd ventricle
reticular nuclei
envelopes each lateral thalamus
intralaminar nuclei
within the internal medullary lamina
relay nuclei
receives info (visual, acoustic, primary somatosensory, motor input)
what are the 3 parts of relay nuclei?
anterior, medial, lateral
anterior relay nuclei function
send + receive signals that affect attention, alertness, learning
hippocampal-diencephalic-cingulate circuits
anterior thalamic nuclei that helps w/long term memory + limbic system
medial nuclei of relay nuclei
sensory integrator
dorsomedial nucleus
responsible for integrating sensory motor, visceral, + olfactory info into emotional state (medial nuclei of relay nuclei)
anteromedial magnocellular
receives olfactory input + establishes reciprocal connections w/olfactory areas on frontal lobe
posterolateral parvocellular
establishes reciprocal connections w/prefrontal cortex, anterior cingulate gyrus, + supplemental motor areas
what are the two subdivisions of the dorsomedial nucleus?
anteromedial magnocellular + posterolateral parvocellular
what part of the relay nuclei is the most clinically relevant?
lateral nuclear group
ventral tier of lateral nuclei
VPL + VPM
dorsal tier of lateral nuclei
MGN, LGN, + pulvinar
ventral anterior nucleus of lateral nuclei function
modulates + relays the signals from the basal ganglia to the premotor cortex. planning and initiating movements
ventral lateral nucleus of lateral nuclei function
central integrative center for motor control. active during passive + active movements
VPL function
input from medial lemniscus + spinothalamic pathways
VPM function
receives projections from the trigeminothalamic pathway
lateral dorsal nucleus of lateral nuclei
helps with vision, long term memory, + emotions. associated with limbic system
MGN function
thalamic relay station of the auditory pathway between inferior colliculus + auditory cortex
LGN function
thalamic relay station for visual pathway
pulvinar function
receives input from visual pathway. exact function is unknown
reticular nuclei function
regulates the activity of the thalamus
intralaminar nuclei function
activation of the cortex from the brainstem reticular formation. sensory-motor integration. speaking and motivation
what thalamic nuclei does not project to the nucleus?
reticular nuclei
primary blood supply to the thalamus
posterior communicating artery
what is the papez circuit?
a circuit that helps with memory retention
what nuclei is the papez circuit associated with?
anterior thalamic nuclei
basal ganglia functions
controlling motor functions, assist learning, regulation of emotion
putamen function
primary addiction center
striatum dorsal function
cellular bridges between caudate + putamen
striatum ventral function
neural interface between motivation + action
substantia nigra function
dopamine released to excite or inhibit
subthalamic nuclei function
modulation of movement
3 main pathways
direct, indirect, + nigrostriatal
direct pathway function
facilitates targeted oriented movements + increases cortical outputs
result of direct pathway
increases motor output
direct pathway excitatory route
cerebral cortex -> striatum
direct pathway inhibitory route
striatum to globus pallidus
indiect pathway function
inhibits competing movements
indirect pathway results
less cortical output
indirect pathway excitatory route
cortex -> striatum
indirect pathway inhibitory route
striatum -> globus pallidus extrena. globus pallidus externa -> subthalamic nuclei
types of dopamine receptors
D1 and D2
D1 receptors are…
excitatory by the direct pathway
D2 receptors are…
inhibitory by the indirect pathway
nigrostriatal pathway function
modulation of direct + indirect pathways
nigrostriatal pathway result
dual effect of exciting the direct pathway while simultaneously inhibiting the indirect pathway
damage to the direct or nigrostriatal pathway results in what type of movement disorder?
hypokinetic movement disorders
damage to the indirect pathway results in what type of movement disorder?
hyperkinetic movement disorders
what is the only purely excitatory pathway in the basal ganglia?
subthalamic nuclei
hyperdirect pathway function
thought to be involved in the suppression/inhibition of movement
what causes parkinson’s?
the loss of dopamine. degeneration of substantia nigra
what is the result of the loss of dopamine?
net inhibition on thalamus
hemiballismus is caused by the damage to?
the subthalamic nuclei
hemiballismus
unilateral wild flinging movements of the extremities contralateral to the lesion in the basal ganglia
what kind of movement disorder is associated with hemiballismus?
hyperkinetic movement
huntington’s disease is often caused by damage to?
enkephalin neurons associated with the indirect pathway
what pathways does huntingtons disease affect?
the indirect pathway
spasticity
abnormal increase in muscle tone or stiffness. UMNL sign
ataxia
irregular, uncoordinated movements caused by lesions of cerebellar circuitry
dyskinesia
abnormal movements caused by basal ganglia dysfunction. ‘abnormal movement’
bradykinesia
slowed movements
hypokinesia
decreased amount of movements
akinesia
no movement
rigidity
increased resistance to passive movement
dystonia
state of abnormal muscle tone resulting in muscular spasm and abnormal posture. typically due to neurological disease
chorea (dance)
neurological disorder characterized by spamodic involuntary movements of the limbs or facial muscles
tics
sudden brief action that is preceded by an urge to perform it and is followed by a sense of relief
what artery is formed when the 2 vertebral arteries merge?
basilar artery
what artery does the vertebral arteries come from?
subclavian arteries
the basilar artery bifurcates to form what artery?
posterior cerebral arteries
what artery joins the vertebral-basilar system with the anterior system?
posterior communicating arteries
what artery completes the circle of willis?
the anterior communicating artery
what artery supplies the thalamus?
posterior cerebral arteries
lenticulostriate artery is a branch off of…?
middle cerebral artery
what does the lenticulostriate artery supply?
caudate nucleus, globus pallidus, putamen, and posterior limb of internal capsule
what is the anterior choroidal artery a branch of?
ICA
what does the anterior choroidal artery supply?
basal ganglia, hippocampus, posterior limb of internal capsule
where is Broca’s area?
inferior frontal gyrus in the dominant hemisphere
where is Brodmann’s area 44?
within Broca’s area, inferior frontal gyrus in the dominant hemisphere
what is Broca’s area responsible for?
production of speech
what is Brodmann’s 44 area responsible for?
production of speech
what artery supplies broca’s area?
middle cerebral artery
what artery supplies brodmann’s area 44?
middle cerebral artery
where is wernicke’s area?
within brodmann’s area 22, posterior 1/3 of superior temporal gyrus
where is Brodmann’s area 22?
posterior 1/3 of superior temporal gyrus
what is wernicke’s area responsible for?
speech comprehension
what is Brodmann’s area 22 responsible for?
speech comprehension
what artery supplies wernicke’s area
inferior middle cerebral artery
what artery supplies Brodmann’s area 22?
inferior middle cerebral artery
what are the positive findings of the vertebral artery test? (5Ds + 3Ns)
diplopia, dizziness, drop attack, dysarthria, dysphagia, nausea, nystagmus, numbness
what does the posterior cerebral artery supply?
inferior temporal lobe + occipital lobes
what does the internal carotid artery supply?
middle cerebral arteries and anterior cerebral arteries
what does the middle cerebral artery supply?
portions of the frontal, parietal, and temporal lobes
what does the anterior cerebral artery supply?
the cortex on the medial surface of the frontal + parietal lobes
Broca’s aphasia
non-fluent aphasia where output of spontaneous speech is diminished and loss of normal grammatical structure
