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Augmented Feedback

Chapter 4

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Note

For those of you who have recently taken KNR 257 (motor learning and performance) you’ll note similarity between the slides. No surprise – it’s the same material.

The difference comes at the end, where more recent findings are reviewed in preparation for next week’s research readings

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Feedback types After performance…

•Sensory feedback (Task-intrinsic)•Visual

•Proprioceptive

•Auditory

•Tactile

•Augmented feedback (Task-extrinsic)•Knowledge of results (KR): information about

the outcome

•Knowledge of performance (KP): information about the movement

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Relative importance of feedback

Sometimes it’s essential for learning•Critical feedback needed for learning is

not “available” or not interpretable for whatever reason•Unseen target

•Disease/disability - loss of sensation

•Task-intrinsic feedback is there, but can’t be understood (timing)

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Relative importance of feedback

Sometimes it may not be needed•Sensory feedback available, understood,

and usable

•Duplicating information that is already available•E.g. Saying “you hit it” when the person can

clearly see they did (not only redundant, but annoying)

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Relative importance of feedback

Sometimes it may enhance learning•They can learn without it, but it speeds

up learning•Complex skills requiring new patterns of

multi-limb coordination

•Aids the search through the “perceptual-motor workspace” (directs attention, aids in cue usage and so on)

•E.g. golf shots, most sports skills

•We’ll discuss this more towards the end of this slide set and next time

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Relative importance of feedback

It may even make things worse•Feedback after every trial (guidance

hypothesis, see later)

•Concurrent feedback (but again see later)•In both cases, the idea is that there’s an

inappropriate amount of attention paid to the augmented feedback

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KR & KP – the lab & the “real world”

Teachers & coaches use KP almost exclusively

Motor learning research has been founded mostly on KR•Problem (external validity)?

•Maybe – needs to be borne in mind for the next few slides

•Don’t just assume it’s all junk though – it has to be argued, and argued well

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The “small & simple” paradigm Principle 1: Feedback must be

prescriptive for folk to learn from it, so we need to study it in such situations

Principle 2: the task must be simple enough that folk can learn it in the time available, so that we can say something about learning•The “small and simple” paradigm met both these

objectives by: •Using simple tasks that only required a small

amount of practice to learn•Using tasks where feedback was essential to

learning (so feedback was prescriptive), and examining how different doses of feedback affected learning

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The “small & simple” paradigm Feedback is prescriptive: provides

guidance towards correct performance

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0% KR50% KR100% KR

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The “small & simple” paradigm Does this mean 100% feedback

improves learning?

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0% KR50% KR100% KR

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The “small & simple” paradigm The guidance hypothesis…why

does this happen?

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1 2 3 4 5 6 7 8 Ret

0% KR50% KR100% KR

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Feedback “scheduling” Reducing guidance…improving

learning•Relative frequency…less is more

•Summary…100% feedback but only 10% of the time

•Self-selected frequency (tend to choose less frequent)•Choose to get feedback when accurate, and

works best when the choice is after performance (Chiviakowsky & Wulf, 2005)

•Bandwidth feedback…

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Feedback “scheduling”0% (no) bandwidth

(100%KR)10% bandwidth (?% KR)

425ms425ms

475ms475ms

525ms525ms

575ms575ms

Target (500ms)

425ms425ms

“…“…..”..”

“…“…..”..”

575ms575ms

‘Correct’

450

550

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Feedback “scheduling” Reducing guidance…improving

learning•Bandwidth feedback…

•Provides guidance (correction) only when necessary (big errors)

•Also tells people NOT to correct when they are reasonably accurate

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Feedback “scheduling” Bandwidth feedback…more than

just a relative frequency effect

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1 2 3 4 5 6 Ret

5% BW"Yoked"

From:

Lee and Carnahan (1990)

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Feedback “scheduling” Bandwidth feedback…effects on

performance?•“Blocking”…similar to guidance ideas

•When you increase the bandwidth, you decrease relative frequency of feedback

•In doing so you reduce “blocking” of sensory feedback

•Maladaptive short-term corrections

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Feedback “scheduling” Bandwidth feedback…effects on

performance?•Maladaptive short-term corrections

•Increased bandwidths reduce attempts to correct very small errors in performance

•Note influence of “no-feedback” trials

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Feedback “scheduling” Bandwidth feedback…learning?

•Larger bandwidths (up to a point) may improve learning

Cause:•Blocking

•Reduction in MSTC.•You want the bandwidth to be sized so that it

reduces RF to an appropriate level and reduce the occurrence of MSTC

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More recent findings

Recent research has suggested guidance ideas are not always accurate•Sometimes frequent feedback seems

desirable even for learning

•The effect of the feedback on attentional focus seems to be important

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High frequency is good Wulf & Shea

(1999)•Concurrent

feedback

•The more often it was presented, the better people performed

•One of the papers reviewed for next week seems to offer an explanation...

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High frequency can be good Retention data from a

soccer kicking study Pay attention to:

• Feedback frequency

• Attentional focus

• Interaction between the two

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RetentionAcc

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Ext-100 Ext-33 Int-33 Int-100

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Next week

Please read the first paper in the list•Read first for comprehension (quickly)

•Read again for critique (slower)•Q1: What do you think of the external validity of

the method of altering focus of attention to improve learning? Think of a new situation, set of ages etc, and whether the findings will change

•Q2: What do you think of the construct validity of the cues used to manipulate focus of attention? (specifically, is it just focus of attention that is manipulated across the two sets of cues?)