Lecture 8

Question 1

GMP stands for

Answer 1

generalized motor program

Question 2

what is GMP

Answer 2

• a pre-organized set of movements commands;

- defines and shapes the movement to be performed

Question 3

open loop control

Answer 3

-closed loop incorporated feedback loops to allow for adjustments as we perform movement

Question 4

open loop system

Answer 4

• is not sensitive to feedback: not able to make a fine adjustments
• no feedback loop or comparator mechanisms
• modifications to skill performance cannot be made by the individual

Question 5

Open loop characteristics

Answer 5

1. Advanced instruction required
2. Program initiated according to instructions, no modifications
3. No errors can be detected
4. Best in a stable environment (predictable)

Question 6

what types of skill in open loop characteristics

Answer 6

• rapid, brief, forceful skills
• speed= little time for feedback
• practice is key-progress
• long term memory

Question 7

open loop pathway is

Answer 7

• linear
• very fast movements are thought to use the open-loop system
• most movements use both open and closed loop
• reflects the functional organization of the motor system

Question 8

central movement organization

Answer 8

Programmed action action is organized in advance triggered as a “whole”
(central movement organization): details of the movement are organized using the central nervous system and then sent to muscles without feedback

Question 9

Evidence for motor programs:

how do we know motor program exist?

Answer 9

a) RT studies in humans
b) removal of feedback in animals and humans
c) impact of clocking movement unexpectedly
d) analysis of behaviors when we stop or change an action
e) movement initiated by a startling stimulus

Question 10

RT evidence

Answer 10

hick’s law- RT is slowed when there is more info to process, processing is slower

• factors affecting the movement programming stage
• RT increases when additional elements in a series are added to the action
• RT increases when more limbs must be coordinated
• RT increases when duration of the movement becomes longer
• thus, more complex movement requires more time for planning/programming =longer RT

Question 11

startled reactions evidence

Answer 11

• involves the startle response- an involuntary action; protective
• series of studies involved the startle RT to investigate movement programming
• subjects are instructed to perform a rapid and forceful movement in response to a moderately intense visual or auditory stimulus
• random, extremely loud auditory signal (130dB)
• RT-shorter duration (up to 100ms shorter) same movement pattern was produced

Question 12

defferentation experiments

Answer 12

• deafferentation: surgically cutting nerve bundles where they enter the spinal cord (monkey)
• motor pathways are not affected
• what can they do without sensory input? Could still move, but did not have fine motor skill anymore
• what have we learned? Quick movements were still done, and couldn’t process the fine motor
• if movement is quick enough, the motor program control the action
• supports the central program concept

Question 13

humans and defferentation

Answer 13

• in humans we can look at pre-existing conditions such as:
  1. lower leg-amputee- no sensory feedback from the knee
• was still able to place the knee in the right place
  2. (diabetic) neuropathy- where sensory feedback has been lost
• still able to use the limb, when they had visual input from that limb

Question 14

what does CPG stand for

Answer 14

central pattern generator

Question 15

central pattern generator

Answer 15

-the idea that motor patterns are genetically defined and organized in the brain stem or spinal cord
command neuron: produces a rhythmic command to the musculature
-almost identical process to the motor program
motor program: learned activities
CPG: genetically defined activities- locomotion, chewing, breathing