Exam 2 Study Guide 3 Flashcards
What is the overall role of the basal ganglia and cerebellum?
adjust activity in descending UMNs
What are the BG and cerebellum influenced by?
- pathways that run through thalamus to different areas
- direct connections with UMNs
What structures are included in the BG?
- caudate
- putamen
- globus pallidus
- STN
- SN
lentiform nucleus
globus pallidus + putamen (shaped like a broad, solid cone)
striatum
putamen + caudate
What structure does dopamine come from?
SNpc
What does dopamine come from (specifically)
- neuromelanin
- expressed in dopaminergic and cholinergic cells in the brain
What are the output nuclei of the BG?
- SNpr
- GPi
How does the BG affect LMNs?
no direct output
- BG » thalamus » UMN tracts in cortex
- BG » PPN » reticulospinal tracts
- BG » midbrain » reticulospinal tracts
What happens with stimulation of PPN?
regulation of postural muscle contractions
Which NT is used to produce excitation in the striatum?
glutamate
What NT adjusts signals to BG output nuclei
dopamine from SNpc (to striatum)
importane of dopamine acting on BG output nuclei
- provide appropriate level of inhibition
- affect voluntary muscles, postural and girdle muscles, walking
BG: receives input from premotor and motor cortex
putamen
BG: processes info within BG circuit
- STN
- SNpc
BG: sends output to motor areas of cerebral cortex via motor thalamus, PPN, and midbrain locomotor region
GPi
“other” roles of BG
- oculomotor
- executive
- behavioral flexibility and control
- libic
blood supply: SN and STN
perforating branches of
- posterior cerebral artery
- posterior communicating artery
blood supply: striatum
perforating branches of MCA (lenticulostriate arteries)
blood supply: globus pallidus
anterior choroidal artery (branch of internal carotid)
blood supply: caudate
branch of anterior cerebral artery (medial striate)
blood supply: thalamus
posterior cerebral artery
What does the cerebellum control?
helps control
- equilibrium
- gross movements of limbs
- fine movements
vestibulocerebellum has to do with
balance
spinocerebellum has to do with
gross movements
cerebrocerebellum has to do with
finer control
What arteries supply blood to the cerebellum?
- SCA
- AICA
- PICA
purpose of cerebellar peduncles
transmit info to and from the cerebellum
What transmits info from the pons to the cerebellum?
middle peduncle
What transmits info from the SC and brainstem to the cerebellum?
inferior peduncle
What transmits info to the red nucleus and thalamus from the cerebellum?
superior peduncle (contralateral side)
