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Updated: Jun 18, 2026

Intracortical Inhibition Within the Primary Motor Cortex Can Be Modulated by Changing the Focus of Attention
Published on: September 11, 2017
Muscle activation patterns during force generation of the index finger
Dan Qiu1, Heidi C Fischer, Derek G Kamper
1Illinois Institute of Technology, Chicago, 60616, USA. dqiu1@iit.edu
Abstract:
The article investigated whether joint postures affect index finger muscle activation patterns. Ten subjects attempted to produce submaximal isometric forces in six orthogonal directions (palmar, dorsal, abduction, adduction, distal and proximal) at each of 9 different joint postures. Activation patterns were recorded from intramuscular electrodes inserted into 6 of the index finger muscles. Post hoc statistical analysis revealed that joint angles significantly affected muscle activation levels for each of the force directions. Activation was especially sensitive to interphalangeal joint angles; changes in these angles led to not only changes in the magnitude of activation but to changes in patterns as well.
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