Temporal Recalibration in Audio-Visual Speech Integration Using a Simultaneity Judgment Task and the McGurk Identification Task

Audio-visual synchrony is important for comfortable speech communication. Previous studies have revealed a temporal window during which human observers perceive physically desynchronized auditory and visual signals as synchronous in both speech and nonspeech signals. This temporal window of audio-visual integration is re-calibrated after adaptation to a constant timing difference between auditory and visual signals in nonspeech. In this study, we investigate whether or not the after-effects of the consequences of temporal recalibration occur even in speech stimuli. Our results suggest that the temporal recalibration occurs not only in nonspeech signals but also in monosyllabic speech.