Sensory Contribution to Skilled Performance

Question 1

What are sensory classifications?

Answer 1

Exteroception: Provides sensory information about the environment that comes primarily from outside the body (vision and audition)
Proprioception: Provide sensory information about the state of the body that come primarily from muscle, joint and movement

Question 2

What systems help proprioception?

Answer 2

Vestibular apparatus: organ in inner ear; info about balance
Joint receptors: receptors in a capsule around the joint; info about extreme position
Muscle spindle: info about changes in muscle length
Golgi tendon organs: info about muscle force
Cutaneous receptors: info about pressure and temperature

Question 3

What is an active movement and passive movement?

Answer 3

Active: you move your body
Passive: someone else moves your body

Question 4

Why can’t we tickle ourselves?

Answer 4

efference copy or feedback signal: information about the intended action or the expected feedback generated before the action begins

Question 5

What are limitations of closed loop control systems?

Answer 5

they are slow:

they only allow for about 3 corrections/sec

Question 6

What is the closed loop control system thought not to control?

Answer 6

Rapid tracking behavior

Discrete task of brief duration

Question 7

What is the evidence of the limitations?

Answer 7

Can’t account for rapid discrete movements

must be a pre-planned, ballistic component to each movement that lasts around 150ms

Question 8

What is the conclusion on closed loop control

Answer 8

Since the reaction to move away from the obstacle happens as fast as the reaction toward the new target, the obstacle response must have been pre-planned

Question 9

What are reflexes?

Answer 9

Stereotyped, involuntary, automatic, rapid response to stimuli

Question 10

What is electromyography (EMG)?

Answer 10

Method for recording electrical activity in a muscle or a group of muscles

Question 11

What is the M1 Response?

Answer 11

Myosynaptic stretch reflex: contraction of stretched muscle within 30-50ms
Important for posture
Thousands can occur at the same time

Question 12

What is the M2 responsive?

Answer 12

Polysynaptic functional stretch response: Contraction of muscles within 50-80ms
At least one synapse in the brain (long loop)
More flexible: influenced by instruction

Question 13

What is the M3 response?

Answer 13

Reaction time response
Passed all stages of processing
Maximally flexible: powerful and sustained

Question 14

What is a triggered reaction?

Answer 14

Complex and coordinated reaction
Non-voluntary
Can effect musculature away from the original stimulation

Question 15

What is the final common path?

Answer 15

resulting movement is a combination of original motor plan, M1, M2, M3 - but only ever one movement

Question 16

How are there loops within loops?

Answer 16

M1 and M2 are closed loops themselves but not closed loop control systems

Question 17

What is the dorsal stream of the visuomotor control?

Answer 17

Specialized for movement, entire visual field; non-conscious, how object movement is directed (parietal lobe)

Question 18

What is the ventral stream?

Answer 18

Specialized in conscious identification, center of field of vision; what is the object (temporal lobe)

Question 19

What is optic flow?

Answer 19

The movement of patterns of light rays from the environment over a person’s retina allowing the person to detect motion position and timing

Question 20

What happens when angles get bigger?

Answer 20

Distance to object get smaller

Question 21

What happens when angles change faster?

Answer 21

Speed is faster

Question 22

What happens when angles change equally about the middle?

Answer 22

The direction is a straight line toward object

Question 23

What happens when both project to same side but change by different amounts?

Answer 23

Direction is to the side of the object

Question 24

What does time-to-contact mean?

Answer 24

measured with tau
Tau=retinal image size/rate of change of retinal size
(for small retinal image sizes)

Question 25

What is the the ventral stream in movement control?

Answer 25

Is crucial to movement planning
-to integrating knowledge about objects within our current action
Also implicated in long latency feedback control