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Does the location of the touch from the contralateral finger application affect grip force control while lifting an
Veena Iyengar1, Marcio J Santos, Alexander S Aruin
1Department of Physical Therapy (MC 898), University of Illinois at Chicago, 1919 W Taylor St, Chicago, IL 60612, United States.
Neuroscience Letters
|September 14, 2007
Summary
Contralateral arm touch reduces grip force during object manipulation, regardless of touch location. This finding supports using a second arm for daily activities and highlights the importance of sensory input for grip control.
Area of Science:
- Neuroscience
- Biomechanics
- Human Motor Control
Background:
- Grip force modulation is crucial for object manipulation.
- Previous research indicated contralateral arm touch reduces grip force.
- The specific effect of touch location on grip force reduction was unclear.
Purpose of the Study:
- To investigate if the location of contralateral arm touch influences grip force reduction.
- To determine if touch on different body parts (wrist, thumb, forearm, object) alters grip force modulation.
Main Methods:
- Participants lifted and transported an instrumented object.
- Grip force was measured under a no-touch condition.
- Grip force was also measured with contralateral index finger touch at the wrist, thumb, mid-forearm, and on the object itself.
Main Results:
- Grip force reduction was observed across all contralateral touch conditions.
- The magnitude of grip force reduction was similar regardless of the touch location on the target arm.
- These results suggest grip force modulation is not dependent on a specific point of tactile contact.
Conclusions:
- Contralateral arm touch consistently reduces grip force during object lifting and transport.
- The location of the tactile stimulus along the target arm does not significantly alter the degree of grip force reduction.
- Findings support the utility of the contralateral arm in activities of daily living and emphasize the role of sensory feedback in motor control.
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