New phenomenon relating to audio-visual interaction in peripheral visual field

摘要

To investigate whether the audio-visual spatial interaction in the peripheral visual field behaves in the same manner as that in the central visual field, points of subjective equality (PSEs) for the coincident spatial position of an auditory and visual stimulus presented in the horizontal plane were estimated by using the method of constant stimuli. Independent, auditory and visual stimuli were simultaneously presented from various positions and observers had to discriminate whether the sound stimulus was presented from the left or the right side of the visual stimulus. Psychometric functions were fitted for each visual location and PSEs were defined as the sound stimulus location for which the proportion of right to left judgments was 50%. The results show that in the peripheral visual field, the PSEs were shifted from the presented visual location towards the extremity of visual field. This PSE-shift phenomenon suggests that audio-visual interaction occurring in the peripheral visual field is different to that occurring in the central visual field.