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Brevity of haptic force perturbations induces heightened adaptive sensitivity.

ABSTRACT: We have exposed human participants to both full-movement and pulsatile viscous force perturbations to study the effect of force duration on the incremental transformation of sensation into adaptation. Traditional views of movement biomechanics could suggest that pulsatile forces would largely be attenuated as stiffness and viscosity act as a natural low-pass filter. Sensory transduction, however, tends to react to changes in stimuli and therefore could underlie heightened sensitivity to briefer, pulsatile forces. Here, participants adapted within perturbation duration conditions in a manner proportionate to sensed force and positional errors. Across perturbation conditions, we found participants had greater adaptive sensitivity when experiencing pulsatile forces rather than full-movement forces. In a follow-up experiment, we employed error-clamped, force channel trials to determine changes in predictive force generation. We found that while participants learned to closely compensate for the amplitude and breadth of full-movement forces, they exhibited a persistent mismatch in amplitude and breadth between adapted motor output and experienced pulsatile forces. This mismatch could generate higher salience of error signals that contribute to heightened sensitivity to pulsatile forces.

SUBMITTER: Wanda PA

PROVIDER: S-EPMC3646637 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Brevity of haptic force perturbations induces heightened adaptive sensitivity.

Wanda Paul A PA Fine Michael S MS Weeks Heidi M HM Gross Andrew M AM Macy Jenny L JL Thoroughman Kurt A KA

Experimental brain research 20130307 3

We have exposed human participants to both full-movement and pulsatile viscous force perturbations to study the effect of force duration on the incremental transformation of sensation into adaptation. Traditional views of movement biomechanics could suggest that pulsatile forces would largely be attenuated as stiffness and viscosity act as a natural low-pass filter. Sensory transduction, however, tends to react to changes in stimuli and therefore could underlie heightened sensitivity to briefer, ...[more]

PMID: 23468159

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Dataset Information

Brevity of haptic force perturbations induces heightened adaptive sensitivity.

Publications

Brevity of haptic force perturbations induces heightened adaptive sensitivity.

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