Exam 2 - Sensorimotor system

Question 1

Like the sensory systems, the sensorimotor system is
A) hierarchical.​

B) parallel.​

C) functionally segregated.​

D) all of the above

Answer 1

D

Question 2

The supplementary motor area and the premotor cortex are in the
A) frontal lobe.​

B) temporal lobe.​

C) parietal lobe.​

D) occipital lobe.

Answer 2

A

Question 3

Electrical stimulation to any part of secondary motor cortex elicits
A) discrete movements of individual muscles.​

B) discrete movements of individual joints.​

C) complex movements, often involving both sides of the body.​

D) loss of equilibrium.

Answer 3

C

Question 4

Major outputs of both the premotor cortex and the supplementary motor area go to the
A) secondary motor cortex.​

B) primary motor cortex.​

C) somatosensory cortex.​

D) frontal eye fields.

Answer 4

B

Question 5

It has been estimated that over half the neurons of the brain are in a structure that constitutes only 10% of the brain’s total mass. This structure is the
A) neocortex.​

B) cerebellum.​

C) hippocampus.​

D) brain stem.

Answer 5

B

Question 6

Posterior parietal association cortex, what information does it receive, what does it output to?

Answer 6

• spatial awareness (position of limbs, external objects)
• receives visual, auditory, and somatosensory information
• outputs to motor cortex

Question 7

Apraxia, what is it usually due to?

Answer 7

• disorder of voluntary movement, problem only evident when instructed to perform an action
• usually due to damage on the L side due to stroke

Question 8

Contralateral neglect

Answer 8

• unable to respond to stimuli contralateral to the side of the lesion, usually seen with large lesions on the right
• damage to R side = neglect to L side of body and vice versa
• ex: shaving one side of your face

Question 9

Dorsolateral prefrontal association cortex, what does it evaluate, what does it output to?

Answer 9

• planning and sequencing
• evaluates external stimuli and initiates voluntary reactions
• output to secondary motor cortex

Question 10

What does the secondary motor cortex get input from and send output to?

Answer 10

• input from association cortex
• output to primary motor cortex

Question 11

What are the 8 different areas of the secondary motor cortex?

Answer 11

• 3 supplementary motor areas
• 2 premotor areas
• 3 cingulate motor areas

Question 12

Mirror neurons

Answer 12

• active when performing an action or watching another perform the same action
• important for empathy and social cognition

Question 13

Stereognosis

Answer 13

recognizing by touch

Question 14

Somatotopic

Answer 14

more cortex devoted to body parts which make many movements

Question 15

Cerebellum, where does it receive input from?

Answer 15

• involved in fine-tuning and motor learning, cognitive response, and coordinating rapid movements
• receives input from primary and secondary motor cortex, and brain stem motor nuclei

Question 16

Basal ganglia

Answer 16

• part of neural loops that receive cortical input and send output back via the thalamus
• modulate motor output and cognitive functions
• fine tune movements

Question 17

Descending motor pathways - dorsolateral tracts

Answer 17

• limbs, distal muscles, and fine tune movements
• terminates in one spinal segment

Question 18

Descending motor pathways - ventromedial tracts

Answer 18

• proximal muscles, posture and whole-body movement (gross motor and trunk movements)
• bilateral innervation

Question 19

Motor unit

Answer 19

a motor neuron + muscle fibers, all fibers contract when motor neuron fires

Question 20

Fast muscle fibers

Answer 20

fatigue quickly - like a sprinter

Question 21

Slow muscle fibers

Answer 21

capable of sustained contraction due to vascularization - like a long distance runner

Question 22

Flexors

Answer 22

bend or flex a joint

Question 23

Extensors

Answer 23

straighten or extend

Question 24

Synergistic muscles

Answer 24

any 2 muscles whose contraction produces the same movements

Question 25

Antagonistic muscles

Answer 25

any 2 muscles that act in opposition

Question 26

Golgi tendon organs

Answer 26

detect muscle tension

Question 27

Muscle spindles

Answer 27

detect length of muscles (stretch)

Question 28

What is the difference in the stretch and withdrawal reflex?

Answer 28

• stretch is monosynaptic and withdrawal is multisynaptic

Question 29

Reciprocal innervation

Answer 29

antagonistic muscles interact so that movements are smooth

Question 30

Response chunking

Answer 30

practice combines the central programs controlling individual response
- getting better with practice

Question 31

Response shifting

Answer 31

shifts control to lower levels, freeing up higher levels to do more complex tasks