The change in perceptual synchrony between auditory and visual speech after exposure to asynchronous speech.

Recent studies have shown that audiovisual synchrony is recalibrated after exposure to asynchronous auditory and visual signals. This temporal recalibration has been shown only under a dual-task situation for speech signals. Here we examined whether the temporal recalibration occurs for audiovisual speech in a single-task situation using an offline adaptation method. In the experiment, participants were exposed to synchronous or asynchronous audiovisual syllables (either congruent or incongruent) for 3 min. The adaptation phase was followed by test trials, in which participants judged whether the auditory or visual stimulus was presented first. Results showed shifts in the point of subjective simultaneity and the sensitivity. Our results suggest that attention to adaptation stimuli is necessary to induce temporal recalibration for speech.