Speed Accuracy Trade-off Flashcards
Lecture 19/20
In a speed-deviation graph what trend is noticed for movements?
Error increases as speed increases
What movements will be noticed for a near target?
-best accuracy
-slowest average speed
What movements will be noticed for a far target?
-low accuracy
-fastest average speed
Index of difficulty =
log2(2A/W)
Why might older adults have a higher y-int for MT?
-baseline movements (unconstrained) are slower than young adults
Why might older adults have a higher/steeper slope?
speed-accuracy tradeoff is more severe
When looking at hand velocity profiles what will you notice about older adults?
-more time in deceleration
-more corrections
What is motor variability proportional to?
amount of force produced
At what % does variability peak?
75% maximal voluntary contraction (MVC)
Fast twitch fibres
-tend to contribute to larger motor units
-recruited later
-larger innervation numbers
Slow twitch fibres
-recruited first
-smaller innervation numbers
MT increases as;
1) width decreases (accuracy demand increases)
2) amplitude increases
Attention
-limited cognitive resource
-used for different tasks/purposes
When may a secondary task not distract from performance?
-when the attentional demands are low
When attentional demands are high how does this impact secondary tasks?
-negative on both sides
(ie. texting and driving)
Three stages of information processing
1) perception (stimulus identification)
2) response selection (decision)
3) response programming (action)
Why is parallel processing beneficial?
-no interference in stimulus identification and response selection (color red, in red)
Can different streams of sensory info be processed simultaneously and independently?
Often - yes! (ie. auditory and visual cues)
controlled processing
-slow, deliberate, consciously aware, high attention demand
-“novies”
automatic processing
-fast, smooth, unconscious performance, low attention demand
-“experts”
What does practice lead to?
automatic processing
What does pressure revert to?
controlled processing
What are temporally and spatially incompatible movements?
-performing multiple (often asynchronous) independent movements
(ie. drummer, patting head/rubbing tummy)
arousal
-level of excitement produced under stress
What is the inverted “U” principle?
-relationship btwn arousal level and performance
-idea of optimal performance at moderate levels of arousal
Can how an athlete handles pressure and arousal be altered?
Yes, with practice
What is the “Individual Zone Optimal Functioning (IZOF)”
-range of arousal levels associated w/ a persons maximal performance
-athlete dependent
When may low arousal be beneficial?
-high complexity tasks
-complex cognitive
-high precision
(ie. golf)
When may high arousal be beneficial?
-power sports
-low precision
-simple technique
(ie. weight lifting)
