Key concepts: Basal ganglia function

Question 1

conditions

Answer 1

parkinsons
huntingdons
stroke

Question 2

contents of the basal ganglia

Answer 2

caudate nucleus
putamen
substantia nigra
sub thalamic nucleus
globus pallidus

Question 3

joint function

Answer 3

facilitating movement
indirectly

Question 4

striatum

Answer 4

caudate nucleus
putamen

Question 5

information pathway of the basal ganglia

Answer 5

cerebral cortex
caudate/ putamen: main input nuclei
globus pallidus/ substantia nigra: main output nuclei
sent projections out by the thalamus

Question 6

information pathway

Answer 6

cerebral cortex
caudate/putamen= main input
globus pallidus/substantia nigra= main output
sent projections out by the thalamus

Question 7

main output of basal ganglia

Answer 7

inhibitory
globus pallidus inhibits the thalamus to prevent unwanted movement

Question 8

direct pathway

Answer 8

excitatory input from Cortex and substantia nigra
inhibitory neuron projection to globus pallidus internus
inhibitiom of inhibitory neuron to the thalamus, increased motor output
more excitation of the cortex

Question 9

indirect pathway

Answer 9

excitatory input from cortex
inhibitory projections form substantia nigra inhibit excitatory cholinergic interneuron
inhibitory neuron to globus pallidus externen
inhibitory neuron to subthalamic nucleus now inhibited
subthalamic nucleus released from inhibition
excitatory projections from subthalamic nucleus now increase thalamic inhibition

Question 10

balance between direct and indirect pathways

Answer 10

smooth movement

Question 11

release inhibition model

Answer 11

direct releases the inhibition of the thalamus so increased cortical ouput
indirect enhances inhibition of the thalamus so decreased cortical output

Question 12

blood supply to the basal ganglia

Answer 12

middle cerebral branch= lenticulostriate
supply basal ganglia and internal capsule