Misbinding of color and motion in human early visual cortex: an event-related potential study

Abstract

Wu et al. (Nature, 2004) described a compelling illusion demonstrating a steady-state misbinding of color and motion. Here, we explored the neural mechanism of the misbinding. In the misbinding condition (MC), the stimulus contained two sheets of random dots, one sheet moving up and the other moving down. On the upward-moving sheet, dots in the right-end area were red and the rest dots were green. On the downward-moving sheet, dots in the right-end area were green and the rest dots were red. When subjects fixated at the stimulus center, they bound the color and motion of the dots in the right-end area erroneously the red dots appeared to move downwards and the green dots appeared to move upwards. In the binding condition (BC), the stimulus was identical to that in the MC except that all red dots moved downward and all green dots moved upward. In the control condition (CC), no dot was presented in the right-end area. In the psychophysical adaptation experiment, we found a significant color-contingent motion aftereffect in the right-end area after adapting to the BC and MC, but not the CC. The aftereffect in the MC followed the prediction from the perceived binding of color and motion, rather than their physical binding. In the ERP adaptation experiment, we found a color-contingent motion adaptation effect reflected as a weaker C1 component after adapting to the BC and MC, but not the CC. The adaptation effect manifested in the C1 peak phase (57-79 ms) in the BC and in the late C1 phase (67-118 ms) in the MC. Dipole source localization showed that V1 and V2 made a major contribution in the two phases, respectively. Taken together, these findings suggest that feature binding and misbinding occur at early processing stages, but in different lower visual areas. Meeting abstract presented at VSS 2014