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Flashcards in Basal Ganglia Deck (20):
1

Basal ganglia

collection of five subcortical nuclei involved in movement
caudate
putamen
globus pallidus
subthalamic nucleus
substantia nigra

2

Basic pathway

input in from most of cortex
projects back to frontal part of cortex through the thalamus

3

Most input to the basal ganglia is received in the _

striatum (caudate + putamen)

4

Most projections from striatum are to _

globus pallidus and substantia nigra

5

Lenticular nucleus

globus pallidus and putamen

6

Functional divisions of globus pallidus

internal segment (GPi)
external segment (GPe)

7

Two parts of substantia nigra

pars compacta (SNc)
pars reticulata (SNr)

8

Main projections of the basal ganglia to the thalamus come from the _ and reach the _

GPi and SNr
VL and VA

9

Two pathways from struatum to GPi

direct pathway
indirect pathway

10

Ansa leticularis

thick fibre bundle
conveys info from GPi to motor thalamus

11

Lenticular fasciculus

conveys info from caudal side of globus pallidus to the VA/VL nuclei of the thalamus

12

Thalamic fasciculus

bundle of fibres headed for the VA/VL of the thalamus
includes ansa fasciculus, lenticular fasciculus and other cerebellothalamic fibres

13

Four cortic-basal loops

Motor
Cognitive
Limbic
Occulomotor

14

Basal ganglia affect the ipsa- or contra-lateral motor cortex/movements of the body

Ipsalateral motor cortex
therefore contralateral movements of the body

15

Consequence of the direct pathway

increase in excitatory drive from thalamus to cortex

16

NT in projections from cortex to striatum

Glu

17

NT in projections from striatum to GPi

GABA

18

NT in projections from GPi to VA/VL

GABA

19

Direct pathway (main function)

Allowing execution of movements by disinhibiting the thalamus

20

Indirect pathway (main function)

Prevention of movements