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bioRxiv · 10.64898/2026.07.01.730966

Stimulus dependent modulation of perceptual filling-in is predicted by the properties of early visual cortex

Razafindrahaba, A.·Koiso, K.·van de Ven, V.·De Martino, F.·De Weerd, P.·Roberts, M. J.
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Abstract

Filling-in occurs during the perceptual disappearance of a blank figure presented on a textured background. Current models of perceptual filling-in are based on a two-stage model where the figure boundary weakens after a period of adaptation, followed by the spreading of the background representation into the region representing the figure. This suggests a competition between figure boundary and background representations whereby filling-in is facilitated by a weaker boundary representation and a stronger background representation. Here, we test this interpretation, by using the oblique effect and surround-modulation suppression, which are functional properties of early visual cortex that modulate the expected strengths of the responses to the background texture and to the figure boundary. In a sample of N=58 participants, we found more filling-in with background textures of cardinal compared to oblique orientations (earlier onset time, with more and longer episodes of filling-in per trial), in line with a known, stronger neuronal response for cardinal than for oblique orientation in early visual cortex. We found more filling-in when the main axis of the rectangular figure was iso-oriented rather than cross-oriented with the background texture (more and longer episodes of filling-in per trial, but no change in onset time), in line with a lower response to oriented stimuli when surrounded by iso-oriented flankers compared to cross-oriented flankers. Overall, our results support the two-stage model and suggest the involvement of early visual cortical areas characterized by the oblique effect and orientation-tuned surround-suppression.

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Razafindrahaba, A., Koiso, K., van de Ven, V., De Martino, F., De Weerd, P., Roberts, M. J.. 2026-07-07. Stimulus dependent modulation of perceptual filling-in is predicted by the properties of early visual cortex. https://doi.org/10.64898/2026.07.01.730966

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