Basal Ganglia Stuff

Question 1

direct pathway of the basal ganglia

Answer 1

-caudete/putamen(striata), globus pallidus internal, thalamus, cortex

Question 2

indirect pathway of the basal ganglia

Answer 2

-caudete/putamen(striata), globus pallidus external, [subthalamic nucleus], globus pallidus internal, thalamus, cortex

Question 3

cortex to caudete/putamen (striata)

Answer 3

excitatory

Question 4

caudete/putamen(striata) to globus pallidus internal

Answer 4

inhibitory

Question 5

globus pallidus internal to thalamus

Answer 5

inhibitory

Question 6

thalamus to cortex

Answer 6

excitatory

Question 7

striata to globus pallidus external

Answer 7

inhibitory

Question 8

globus pallidus external to globus pallidus internal

Answer 8

inhibitory

Question 9

globus pallidus external to subthalamic nuclei

Answer 9

inhibitory

Question 10

subthalamic nuclei to globus pallidus internal

Answer 10

excitatory

Question 11

inhibits unwanted movements

Answer 11

indirect pathway

Question 12

allows for wanted movements

Answer 12

direct pathway

Question 13

substantia nigra pars compacta

Answer 13

contains dopaminergic neurons which activate metabotropic receptors on the caudate/putamen(striata) to either inhibit the indirect pathway or excite the direct pathway

Question 14

tonic

Answer 14

consistently occurring without external forces

Question 15

transient

Answer 15

temporary/spontaneous

Question 16

similarities between globus pallidus and the substantia nigra retriculata

Answer 16

-both send inhibitory information to the thalamus
-both receive information from the subthalamic nuclei via indirect pathway
-both receive inhibitory information from the caudate/putamen (striata) when it is active

Question 17

where does the striatum receive glutamatergic info from

Answer 17

via the corticospinal pathway

Question 18

which cortical inputs do not project to the striatum

Answer 18

primary auditory and visual cortex
audio and visual related info can still be projected to striatum via related parts of the brain

Question 19

where do layer 5 cortex pyramidal neurons synapse with the striatum

Answer 19

on the base of the dendrite of the medium spiny neurons

Question 20

where do inhibitory local circuit neurons synapse with the striatum

Answer 20

on the soma of medium spiny neurons (does not degrade down the dendrite and has the most influence at the axon hillock, this is why medium spiny neurons are usually inhibited and u are not always moving randomly)

Question 21

how are the globus pallidus and substantia nigra pars reticulata affected by the inhibition of the striatum

Answer 21

the inhibition of the striatum allow the globus pallidus and substantia nigra pars reticulata to fire spontaneously

Question 22

how are the globus pallidus and substantia nigra pars reticulata affected by the disinhibition of the striatum (via adequate cortical input

Answer 22

the substantia nigra reticulata and globus pallidus are no longer firing spontaneously

Question 23

inactive parts of the system at rest (no cortical input)

Answer 23

striatum, thalamus, cortex
subthalamic nuclei

Question 24

active parts of the system at rest (no cortical input)

Answer 24

globus pallidus internal, globus pallidus external

Question 25

what is the direct pathway doing at rest

Answer 25

no voluntary direct movement is taking place

Question 26

what is the indirect pathway doing at rest

Answer 26

the indirect pathway is not effectively inhibiting involuntary movement. The gpE and gpI are tonically firing, so you have tonic inhibition of the gpI resulting in transient excitation by the thalamus and involuntary sporadic movements happening

Question 27

what is the collicular pathway doing at rest

Answer 27

-because the striatum is not actively inhibiting the snpr, substantia nigra pars reticulata is tonically inhibiting the superior colliculus and the eyes stay fixated