Sound Reduces Visual Chronostasis Caused By Saccade

The duration of visual stimulus is grossly overestimated when it is flashed during saccadic eye movement,which is known as saccadic chronostasis.Previous studies on time perception have found that task-irrelevant sounds can strongly alter the perceived duration of visual stimuli,temporal information from visual and auditory modality is assumed to interact,but little is known,whether the presentation of sound can reduce the duration overestimation of the visual stimulus.Using the comparative time judgment in Experiment 1,the participant was instructed to compare the duration of the probe to that of the standard under pure visual(?)condition?pure auditory(A)condition,probe stimulus for audiovisual stimulus and standard stimulus for visual stimulus(CV)condition,probe stimulus for audiovisual stimulus and standard stimulus for auditory stimulus(CA)condition dxiring saccade and fixation,to investigate whether the perceived duration of visual and auditory stimulus will be affected by saccade,and whether the presentation of sound can reduce the duration overestimation of the visual stimulus.The results showed that the duration of the visual stimulus,not sound,was overestimated during saccade.Moreover,the presentation of sound reduced the duration overestimation of the visual stimulus during saccade.In order to verify whether the temporal ventriloquism effect(synchronous sound may"attract" the onset of the visual stimulus that is advanced by saccade)is one of the reasons for the reduction of duration overestimation of visual stimulus in experiment 1,the Experiment 2 investigate whether sound can "attract" the onset of the visual stimulus that is advanced by saccade,thereby reducing the duration overestimation of visual stimulus during saccade,when visual stimulus and sound are presented synchronously or asynchronously.Based on the eondition of V in Experiment 1,a sound with duration of 16ms was presented around the onset of the probe stimulus.The auditory stimulus was presented synchronously with the visual stimulus or the auditory stimulus was presented before or after the onset of the visual stimulus.The results showed that temporal ventriloquism effect was observed when sound was simultaneous and trailing visual stimulus,thus reducing the duration overestimation of the visual stimulus.However,the duration of visual stimulus was still overestimated when the sound was presented before the visual stimulus.