L29

Question 1

what is the role of the basal ganglia

Answer 1

important role in fine tuning the initiation of correct movement programs
also magnitude and velocity of movements

Question 2

what is the striatum made from

Answer 2

caudate and putamen

Question 3

what type of nuclei are in the striatum

Answer 3

input nuclei

Question 4

what type of projections does the subthalamic nucleus have

Answer 4

excitatory

Question 5

where does the striatum receive input from

Answer 5

cerebral cortex
thalamus
substantia nigra pars compacta

Question 6

what are the major output structures

Answer 6

globus pallidus internus
substantia nigra pars reticulata

Question 7

where do topographical loops project from

Answer 7

pre motor
primary motor
primary somatosensory cortex

Question 8

where do topographical loops project into

Answer 8

putamen

Question 9

neuron in the ___ have background firing why

Answer 9

Gpi and to inhibit movement

Question 10

what helps shape the activation of direct and indirect pathway activation

Answer 10

motor and sensory information

Question 11

draw and explain the direct pathway

Answer 11

cortex – striatum – gpi – thalamus – cortex

Question 12

what does the activation of the direct pathway ultimately lead to

Answer 12

activation or excitation of motor cortex

Question 13

draw and explain the indirect pathway

Answer 13

cortex – striatum – gpe — stn — gpi — thalamus — cortex

Question 14

what does the indirect pathway ultimately result in

Answer 14

inhibition of movement

Question 15

what neuro transmitter is being added in the nigrostriatal pathway

Answer 15

dopamine

Question 16

what type of receptors does the direct pathway have

Answer 16

D1 = depolarize

Question 17

what type of receptors does the indirect pathway have

Answer 17

D2 = hyperpolarize

Question 18

where is the dopaminergic coming from

Answer 18

substantia nigra pars compacta

Question 19

what does the dopamine do to both pathways

Answer 19

excites direct path
inhibits indirect path

Question 20

what does the nigrostriatal path ultimately lead to

Answer 20

excitation of the motor cortex through both paths

Question 21

what is parkinsons disease the result of

Answer 21

breakdown of dopamine recpetors

Question 22

what does the break down of dopamine receptors result in

Answer 22

more activity of indirect pathway as less inhibtion of indirect pathway is occuring
also less activity of direct pathway

Question 23

symptoms of parkinsons

Answer 23

slowed movements
rigidity
dyskinesia
poor movement initiation
stooped posture
masked face

Question 24

what is the treatment method L-Dopa for parkinsons

Answer 24

a dopamine agonist that converts into dopamine = restore dopamine levels in the brain

Question 25

what is the con for using L dopa

Answer 25

the drug becomes ineffective over time

Question 26

what is pallidotomy

Answer 26

neurosurgical procedure in which part of the globus pallidus is destroyed

Question 27

what does pallidotomy do

Answer 27

less GPi = less inhibition to the thalamus = more MC activity

Question 28

what does STN stimulation do

Answer 28

reduces excitability of STN cells = less excitability on GPi

Question 29

what is huntingtons disease

Answer 29

brain disorder caused by a defective gene that tips basal ganglia output in favour of the direct pathway as selective loss of neurons in the indirect pathway occurs

Question 30

symptoms of huntingotns

Answer 30

involuntary continuous movements
decline in thinking/reasoning skills
choreiform movements (jerky)