Motor Learning Chapter 6

Question 1

Fits law states that:

Answer 1

• As speed increases: accuracy declines

- as movement time increases, so does movement difficulty

Question 2

Errors increase with:

Answer 2

• increase in movement distance

- increase in movement time

Question 3

fitts law states that movement time (MT) is constant whenever:

Answer 3

the ratio of the movement amplitude (A) to target width (W) remains constant.

Question 4

Speed accuracy trade off states that:

Answer 4

• characteristics of motor skill in which the speed of the movement is influenced by accuracy demands
• essentially individuals substitute accuracy for speed or speed for accuracy

Question 5

Linear speed-accuracy trade-off states that:

Answer 5

-Increases in movement distance and decreases in mt can be traded off with each other to maintain movement accuracy

Question 6

closed loop control is more ______ and has more time for correction
-slow

Answer 6

-accurate

Question 7

open loop control is faster and less _____

Answer 7

-accurate

Question 8

What then are the sources of error in quick movements?

Answer 8

system noise

Question 9

The characteristics of noise are:

Answer 9

• System noise (inconsistency/ variability) -> processing of CNS
• When signals are not perfect, they’re often times a source of noise.
• CNS -> nerve impulse into motor activation
• more muscle contraction -generates more noise (up to 50-70%)
• increase in number of muscles generates more movement noise
• if too many or too few motor units are recruited= error
• unintended reflexes can also be a source of error

Question 10

what are the two speed accuracy trade-off expectations?

Answer 10

• Timing accuracy

- Spatial accuracy

Question 11

Timing accuracy:

Answer 11

accuracy required of rapid movements in which accuracy of the movement time is important to the performance

Question 12

Spatial accuracy:

Answer 12

accuracy of aiming movements in which spatial position of the movement’s end point is important to performance

Question 13

rapid striking tasks speed up:

Answer 13

movement errors

Question 14

speeding movement errors results in :

Answer 14

time timing errors and spatial errors

Question 15

Bimanual Fitts tasks:

Answer 15

both limbs could be assigned identical movements or incongruent movements

Question 16

Bimanual aiming tasks

Answer 16

• the explanatory power of fitts law is reduced when separate and incongruent tasks demand are required of two limbs
• the finding could be a result of an attempt be the executive to deal with an overloaded attentional demand by issuing a single motor program that control both limbs
• these findings support a view that on which the mt and kinematics for both limbs are not determined independently built rather by a joint command