Hierarchical Controls of Movement

Question 1

What are the components of hierarchy?

Answer 1

Neocortex contributes to our conscious control of movement, whereas the brainstem and spinal cord are involved in the more automatic actions that we make - normally functions as a whole

Question 2

Who said that the nervous system was organised into layers?

Answer 2

Jackson - the nervous system as organised as successive layers, with higher levels controlling complex behaviour by acting through lower levels

adapted from evolution - each nervous system has developed at different Tims, which means each one must have some sort of functional independence

Question 3

How are movements initiated?

Answer 3

1930’s - firstly perform an action, wait for feedback, then perform the action again

1950’s - if you had to wait for feedback, would take ages. Lashley - movements for skilled actions are performed quickly to rely on feedback, movement modules preprogrammed by the brain and produced as a unit or motor sequence. Complex behaviours require selecting and executing multiple movement sequences - as one sequence is executed, the next sequence is being prepared

Question 4

What is the movement module?

Answer 4

Enables us to move a lot quicker, we have these in our brain

Question 5

What is the critical area for movement?

Answer 5

Frontal lobes

Question 6

What does the frontal lobes consist of?

Answer 6

Prefrontal cortex
Premotor cortex
Primary motor cortex

Question 7

What is the prefrontal cortex?

Answer 7

Planning of movements, specifying the goal (e.g. deciding to play with iPhone). In front of the cortex, planning and making decisions

Question 8

What is the premotor cortex?

Answer 8

Organizes motor sequences (e.g. select movements appropriate to the context of the action)
Information goes from the pre frontal cortex to the premotor cortex

Question 9

What is the primary motor cortex?

Answer 9

Produces specific, skilled movements

Sends information to the motor cortex - allowing us to perform the movement. For example, doing the pincer grip

Question 10

What happens to animals with damage to the premotor cortex?

Answer 10

They cannot put motor sequences together

Give monkeys lesions to the pre motor cortex only - they are unable the perform sequences and select appropriate action

Question 11

What does the primary motor cortex allow?

Answer 11

Pincer grip - which monkeys can’t do

Question 12

What happens when subjects use a finger to press a lever?

Answer 12

Blood flow increases in the hand area of the primary somatosensory and primary motor cortex

Question 13

What happens when subjects perform a sequence of movement?

Answer 13

Blood flow increases in the premotor cortex

Question 14

What happens when subjects use a finger to find a route through a maze?

Answer 14

Blood flow increases in the prefrontal, temporal and parietal cortex