Presentation Information
[P1-37]Basic mechanism underlying the audio-visual temporal recalibration for the long stimuli
*Yaru Wang1, Makoto Ichikawa1 (1. Chiba University (Japan))
Keywords:
Multiple sensory processing,Audio-visual stimuli,Temporal order judgement,Temporal lag,Awareness
When audio-visual stimuli are presented with a consistent temporal asynchrony for a few minutes, the perceived asynchrony between the stimuli would be reduced (audio-visual temporal recalibration). The present study aims to examine the mechanism underlying the audio-visual temporal recalibration for the stimuli whose onsets are distinguishable from their offsets. In Experiment 1, we investigated the responsibility of the onset-offset channel, which independently processes the onset and offset of stimuli, for the audio-visual temporal recalibration. Participants were exposed to either asynchronous onsets or offsets with a constant temporal lag (±240ms; negative lag means that the visual stimulus followed the audio stimulus) in the adaptation phase, and then made temporal order judgments for the offsets in the test phase. We found no temporal recalibration. In Experiment 2, we investigated the responsibility of the subject binding between the onset (offset) of the audio stimulus and the offset (onset) of the visual stimulus, for the audio-visual temporal recalibration. Participants were exposed to asynchronous onsets and offsets with a constant temporal lag (0, ±240ms; the audiovisual stimuli overlapped with each other only in the negative lag condition) in the adaptation phase, and then made temporal order judgments for the offset and onset of audio-visual stimuli in the test phase. We found the temporal recalibration only for the -240ms condition. In Experiment 3, we investigated the necessity of overlap between the audio-visual stimuli, for the audio-visual temporal recalibration. Participants were exposed to synchronous onsets and offsets with a constant temporal lag (-240ms) in the adaptation phase, and then made temporal order judgments for the offset and onset of the stimuli in the test phase. We found no temporal recalibration. These results suggest that the audio-visual temporal recalibration depends upon subjective binding between the onset and offset of audio-visual stimuli.