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Force matching: motor effects that are not reported by the actor
Michał Pawłowski1,2, Joseph M Ricotta3, Sayan D De3
1Department of Kinesiology, The Pennsylvania State University, University Park, PA, 16802, USA. m.pawlowski@awf.katowice.pl.
Experimental Brain Research
|April 23, 2024
Summary
Force matching unexpectedly accelerated finger force drift, contrary to predictions. This study investigates motor control and sensory feedback during force production tasks.
Area of Science:
- Motor Control
- Human Physiology
- Neuroscience
Background:
- Unintentional force drifts occur during sustained force production.
- Previous research suggested force matching might mitigate these drifts.
Purpose of the Study:
- To investigate the effect of contralateral force matching on unintentional finger force drifts.
- To examine the impact of visual feedback on force production and matching.
- To test the hypothesis that force matching reduces force drift.
Main Methods:
- Participants performed force production and matching tasks with both hands.
- Constant submaximal forces (20% MVC) were produced using index and ring fingers.
- Visual feedback conditions varied, and force matching was initiated at different time points.
Main Results:
- Force matching, contrary to predictions, briefly accelerated force drift in the task hand.
- No significant effect of force matching was observed on the force drift of uninstructed (enslaved) fingers.
- Force drifts were interpreted as resulting from command signal variations to antagonist muscles.
Conclusions:
- Force matching does not mitigate, and may initially worsen, force drift during sustained contractions.
- The findings suggest limitations in how motor commands are perceived and integrated into motor control.
- Motor control theories involving spatial referent coordinates may explain observed force drifts.
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