Lecture 1 - Motor Control

Question 1

What is the difference between a motor skill and a movement

Answer 1

Movements are components of motor skills. Motor skill is an activity that requires a movement to achieve a goal. Movement is a specific limb motion.

Question 2

Why do we need to differentiate movements and skills?

Answer 2

Learn movements before skills
Multiple movements can accomplish similar skills
Measured differently (skills–> outcome, movement–> specific characteristic)

Question 3

What are the 4 Motor Control Problems?

Answer 3

Degrees of Freedom
Perceptual-Motor integration
Serial-order
Skill acquisition

Question 4

Describe Degrees of Freedom and list solutions

Answer 4

How to control the muscles and joints to perform a particular action
Solutions: Efficiency, Synergy, Rely on mechanics
Move smoothly, avoid extremes
Lock joints to remove DOF
Use gravity/inertia to avoid having to activate muscles

Question 5

Describe the serial order problem

Answer 5

Organize the sequence of components of a movement
Planning –> thinking ahead
Co-articulation –> simultaneous motion instead of needing to put it in order

Question 6

Describe the perceptual-motor integration

Answer 6

Integrating sensory information and acting on this information
Movement usually enhances perception (counter example: saccadic suppression)
Have neurons code info in multiple coordinate systems
Neurons transfer sensory input into motor signals
Use feedback and feedforward processes

Question 7

Describe the skill-acquisition problem

Answer 7

How do we learn?
Are we born with skills?
How do we remember skills?

Question 8

What are the 3 main factors and their subfactors of movement

Answer 8

1) Individual
Action, cognition, perception
2) Environment
Regulatory, non-regulatory
3) Task
Stability, Mobility, Manipulation

Question 9

Describe cognition

Answer 9

attention, motivation, and emotional aspects of motor control

Question 10

Describe perception

Answer 10

integration of sensory information into meaningful info
Info about state of body and environment
Sensory contribution to movement

Question 11

Describe action

Answer 11

How a movement is controlled, understanding output from nervous system to effector systems

Question 12

Describe stability

Answer 12

stable base of support

Question 13

Describe mobility

Answer 13

changing or moving base of support (includes stability constraints)

Question 14

Describe manipulation

Answer 14

Grasping, carrying, etc

Question 15

Describe regulatory

Answer 15

Environmental features that directly affect movement

Question 16

Describe non-regulatory

Answer 16

Environmental features that may affect performance but movement doesn’t need to conform to these features

Question 17

What are the 3 classifications of motor skills and what do they describe?

Answer 17

1) Size of muscles needed (Gross v fine)
2) Specificity of beginning and end of movement (discrete [defined start and end point], serial [series of discrete tasks], continuous [individually defined end point])
3) Stability of the environment (open [unpredictable environment] v closed [predictable environment])

Question 18

Give an example of gross and fine movements

Answer 18

carrying boulder v threading needle

Question 19

Give an example of serial, discrete, and continuous movements

Answer 19

playing piano, kicking soccer ball, swimming

Question 20

Describe the different types of tracking

Answer 20

1) pursuit –> both actions of target produced by experimenter, and subject movements displayed
2) step –> target unpredictably moves between locations, and subject must follow
3) compensatory –> experimenter variations and subjects movements produce one target value

Question 21

How do we stay standing

Answer 21

Use COP to keep COM within BOS
COM controlled by nervous system
BOS = area of body in contact with support surface

Question 22

What are the 3 components of reaching/grasping

Answer 22

Transport to spatial location
Orientation to align
Preshaping of digit configuration

Question 23

What are the 3 pieces of information for reaching/grasping

Answer 23

Characteristics of target
Initial configuration of body
Location of target