Intrinsic timescales of sensory integration for motion perception

A subject-specific process of accumulation of information may be responsible for variations in decision time following visual perceptions in humans. A detailed profile of this perceptual decision making, however, has not yet been verified. Using a coherence-varying motion discrimination task, we precisely measured the perceptual decision kernel of subjects. We observed that the kernel size (decision time) is consistent within subjects, independent of stimulus dynamics, and the observed kernel could accurately predict each subject’s performance. Interestingly, the performance of most subjects was optimized when stimulus duration was matched to their kernel size. We also found that the observed kernel size was strongly correlated with the perceptual alternation in bistable conditions. Our result suggests that the observed decision kernel reveals a subject-specific feature of sensory integration.