Motor Cortex

Question 1

Evidence for somatotopy : mapping the cortex

Answer 1

1.developments in anaesthesia allowed for stimulation of animal brains during surgery
2.electrical stimulation of sections of the cortex caused movements of contra lateral body parts
3.identified 15 distinct sections of the cortex that precisely control movement
4.removal of the cortical sections resulted in no movement

Question 2

Evidence for somatotopy : the Montreal procedure

Answer 2

1.treated patients with severe epilepsy by destroying nerve cells in the brain where the seizures originated
2.before the surgery penfield stimulated the brain with probes while the patients were awake to allow for more accurate surgery
3. Allowed penfield to map the sensory and motor corticles

Question 3

Recording from the motor cortex:in vivo measures

Answer 3

1.electrical activity of cells within the brain can be recorded using direct and indirect measurement techniques

2.EEG uses electrodes placed on the skull to record brain activity

3.ECoG uses electrodes placed on the brain tissue to record brain activity

Question 4

How to extract movement info from the cortex

Answer 4

1.microelectrode array inserts into the macaque motor cortex
2.single unit recordings made during reaching movements in multiple directions

Question 5

Motor cortex also represents force output:

Answer 5

Not only does the motor cortex represent movement direction but there is also evidence that it represents force.

Question 6

What do motor cortex cells encode

Answer 6

Both kinetics and kinematics