C.2 · 运动学习

What would explain this observation?

• A learner adjusts a slow movement after seeing an error, but a very fast action may end before visual feedback can change it. Timing constrains the role of feedback.
• Start with a prediction. State the quantities or features you would compare, then decide what evidence could distinguish two explanations.

Build the model

• Open-loop control emphasizes a pre-organized command during an action; closed-loop control uses feedback to compare the result with a goal and modify control. Many sporting actions combine feedforward preparation with feedback. Intrinsic feedback arises from the performer’s sensory information, while augmented feedback 附加反馈 is additional information supplied by another source.
• augmented feedback: Additional task information supplied beyond the performer’s own sensory feedback; knowledge of results 结果反馈: Feedback about the outcome of an action.

Choose evidence that can test it

• Distinguish knowledge of results from knowledge of performance. A score reports the outcome; a description of arm position reports movement features. Feedback can guide practice, yet immediate success with continuous prompts may not persist when prompts are removed. Retention 保持 and transfer therefore provide stronger learning evidence than one practice score.
• Use a voluntary, low-risk seated target or tracing task. Define the outcome, keep practice opportunities equal, give an agreed feedback schedule and assess delayed performance without feedback. Counterbalance group order where feasible and use anonymous records. Do not claim the task completely models elite performance.

Work from known quantities

• State the known values and their units. Choose the relation because its assumptions fit this case, then rearrange before substitution.
• Known: one trial provides 20 attempts and 14 successes, or 70%. A delayed no-feedback test provides 20 attempts and 10 successes, or 50%. The decline is 20 percentage points, not a 20% relative decline; relative decline is (14−10)/14 ×100, approximately 28.6%. The observation supports investigating dependence on prompts, not a guaranteed explanation.

Example:

Success rate changes from 80% in practice to 55% in retention. Find the decrease in percentage points. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.

Check the conclusion and its limits

• Open-loop and closed-loop are models, not a claim that an athlete’s nervous system uses only one mechanism. Feedback timing, task complexity and sensory availability affect what can be inferred.
• Return to the original observation. Explain what the result supports, which conditions it assumes, and one way to test a competing explanation.

Warn:

A strong score with continuous prompts proves lasting motor learning. This claim is false: Open-loop and closed-loop are models, not a claim that an athlete’s nervous system uses only one mechanism. Feedback timing, task complexity and sensory availability affect what can be inferred.

Key:

Motor control: feedback, timing and evidence: Distinguish knowledge of results from knowledge of performance. A score reports the outcome; a description of arm position reports movement features. Feedback can guide practice, yet immediate success with continuous prompts may not persist when prompts are removed. Retention and transfer therefore provide stronger learning evidence than one practice score.