Sensorimotor System

Question 1

3 principles of sensorimotor function

Answer 1

Hierarchical organization

Motor output is guided by sensory input

Learning changes the nature and locus of sensorimotor control (conscious to automatic)

Question 2

Posterior parietal ass cortex

Answer 2

Integrates info from body parts and external objects.

Receives visual. Auditory. Somatosensory Info.

Outputs to motor cortex:
Including dorsateral prefrontal ass cortex, secondary motor cortex, frontal eye lid.

Question 3

Apraxia

Answer 3

Damage to posterior partietal cortex

Disorder of voluntary movement. Problem only evident when instructed to perform an action. Usually consequences of damage to area on left.

Question 4

Dorsolateral prefrontal ass cortex

Answer 4

Input from posterior parietal cortex

Output to secondary motor cortex. Primary motor cortex. And frontal eye field.

Dorsateral prefrontal ass cortex evaluates external stimuli and initiates voluntary reactions. Supported by neuronal responses.

Question 5

Seoncdary motor cortex

Answer 5

Input mainly from association cortex

Output mainly to primary motor cortex

Involved in programming movements in response to input from dorsolateral prefrontal cortex

Active during imagining or planning of movements

Question 6

Mirror neurons

Answer 6

Active when performing an action or watching another perform the same action

Monkey studies:

• grasping or watching another grasp a particular object but not another
• grasping or watching an object for a specific purpose but not for another purpose.

Possible neural basis of social cognition (knowledge of others mental processes)

Likely to be found in humans: indirect evidence from fMRI studies.