The temporal window of audio-tactile integration in speech perception

Asynchronous cross-modal information is integrated asymmetrically in audio-visual perception. To test whether this asymmetry generalizes across modalities, auditory (aspirated "pa" and unaspirated "ba" stops) and tactile (slight, inaudible, cutaneous air puffs) signals were presented synchronously and asynchronously. Results were similar to previous AV studies: the temporal window of integration for the enhancement effect (but not the interference effect) was asymmetrical, allowing up to 200 ms of asynchrony when the puff followed the audio signal, but only up to 50 ms when the puff preceded the audio signal. These findings suggest that perceivers accommodate differences in physical transmission speed of different multimodal signals.