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bioRxiv · 10.64898/2026.06.30.735222

The influence of virtual visual stimulus amplitude to induce standing postural responses

Toussaint--Malard, B.·Danion, F.·Le Mouel, C.·Decatoire, A.·Laguillaumie, P.·Billot, M.·Tisserand, R. R.
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Abstract

Upright postural control during movement relies on multisensory integration. Yet, the frequency-specific contribution of vision remains poorly characterized in virtual reality (VR). This study investigated how multi-sine visual stimulation amplitude delivered in VR influences standing postural responses. Fifteen healthy adults stood on a force plate wearing a VR headset. Visuo-postural coupling was assessed through coherence and gain analyses between a multi-sine signal (10 sinusoids, 0.12 to 1 Hz) oscillating a virtual environment in one of four amplitudes (0.5, 1, 2, 4 degrees peak-to-peak) and the anteroposterior whole-body angle. All amplitudes elicited measurable postural responses. Increasing amplitude significantly increased postural oscillation and tended to increase coherence, while gain significantly decreased. These results are consistent with a nonlinear control system. The 2 degrees amplitude elicited the largest gain with significant coherence across all stimulated frequencies, suggesting it is suitable for studying visual contributions to postural control during movement execution.

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Toussaint--Malard, B., Danion, F., Le Mouel, C., Decatoire, A., Laguillaumie, P., Billot, M., Tisserand, R. R.. 2026-07-04. The influence of virtual visual stimulus amplitude to induce standing postural responses. https://doi.org/10.64898/2026.06.30.735222

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