Lecture 19 - Subcortical contributions to motor control

Question 1

name 4 conditions which can result from cerebellar lesions

Answer 1

tremor, hypermetria, dysdiadochokinesia and ataxic gait

Question 2

in the cerebellar microcircuit purkinje cells form one layer with their axons going where?

Answer 2

white matter

Question 3

parallel fibres cross with the dendrites of which type of cell in the cerebellar microcircuit?

Answer 3

purkinje cells

Question 4

simple spikes which form the standard action potential are based on which ion? which type of fibre elicit them? via which mechanism?

Answer 4

sodium, parallel fibres, temporal summation

Question 5

complex spikes are associated with large depolarisations causing a spike in which ion?

Answer 5

calcium

Question 6

in which type of spike is there 1:1 coupling with climbing fibre and a low rate?

Answer 6

complex spikes

Question 7

in which type of spike is there a high rate?

Answer 7

simple spikes

Question 8

give an example of a type of cell in which the AP is similar to that of a complex spike?

Answer 8

cardiac cell

Question 9

basal ganglia are a group of neurons in which part of the brain? what do they surround?

Answer 9

in midbrain, surround thalamus

Question 10

which nucleus sits at the top of the basal ganglia? which group of neurons sit at the bottom and have a darker appearance?

Answer 10

caudate nucleus, substantia nigra

Question 11

which group of neurons in the brain are lost in parkinsons (dopaminergic transmission decreases)?

Answer 11

susbtantia nigra

Question 12

name some of the traits associated with basal ganglia disease: Parkinson’s

Answer 12

hypokinesia, akinesia, bradykinesia, rigidity, tremor, micrographia, shuffling gait, lack of accessory movements, impaired balance

Question 13

in huntington’s chorea which type of striatal cells are lost which inhibit GPe?

Answer 13

GABAergic

Question 14

in parkinsons a treatment is to inhibit the subthalamic nucleus, what does this reduce the activity of?

Answer 14

GPi

Question 15

when do sustantia nigra dopaminergic cells fire?

Answer 15

with reward

Question 16

name 4 other basal ganglia pathologies other than parkinson’s

Answer 16

tourette’s, OCD, addiction, dystonia

Question 17

the spiny neurons of the striatum recieve inputs from which 2 brain areas on their dendrites? which substance can change inputs here?

Answer 17

cortex and thalamus, dopamine

Question 18

the cortex presents the basal ganglia a menu of movement options which are fed back to the cortex. the one which gives the most what is selected?

Answer 18

reward