Action

Question 1

Which parts of the brain are involved in action? (5)

Answer 1

~ basal ganglia
~ cerebellum
~ primary motor cortex (M1)
~ secondary motor cortex –> premotor cortex (PMC) + supplementary motor cortex (SMC)
~ association motor areas –> Broca’s area, area 8, parietal areas

Question 2

Basal ganglia

Answer 2

~ controls what signals thalamus send to motor cortex –> gatekeeper
~ subcortical

Question 3

Cerebellum

Answer 3

~ balance and fine co-ordination
~ attention, planning and language processing
~ creates forward models to predict sensory
~ subcortical

Question 4

Primary motor cortex (M1)

Answer 4

~ receives input from other motor areas
~ largest output signal = spinal cord
~ contains a somatotopic map of body

Question 5

Secondary motor areas

Answer 5

~ includes PMC + SMC
~ planning and movement control
~ contains multiple somatotopic maps

Question 6

Association motor areas

Answer 6

(posterior/inferior) parietal areas = space rep., sensory integration
area 8 = eye movement
Broca’s area = speech production

Question 7

BMI

Answer 7

Brain-machine interface
~ translates neural signals into commands capable of controlling external technology
e.g. robotic arm

Question 8

Population vectors

Answer 8

capture the distributed representation over many neurons of movement

Question 9

Mirror neurons

Answer 9

neurones in premotor and parietal cortex that respond when a specific action is observed = perception + action representational overlap

Question 10

Affordance competition hypothesis

Answer 10

(Giesk, 2007)

multiple action plans are developed in parallel, the action selection and specification occurs together

Question 11

Describe Basal ganglia as a gatekeeper

Answer 11

~ when it is activated is activates a specific motor plan on thalamus and then cortex switches off = movement initiation
~ winner-takes-all network –> only one motor plan occurs at once

Question 12

Name two basal ganglia diseases

Answer 12

Huntington’s disease

Parkinson’s disease

Question 13

Huntington’s disease

Answer 13

Inhibitory pathway to globus pallidus is reduced
= reduced thalamus inhibition
= greater excitation of thalamus + motor cortex
= involuntary movements

Question 14

Parkinson’s disease

Answer 14

Loss of dopaminergic neurones in substantia nigra
= increased thalamus inhibition
= diminished motor cortex excitation
= absence or reduction of voluntary movements