Abstract
Audio-visual integration induces some illusions, including fission and fusion illusions. In fission and fusion illusions, the number of perceived visual flashes was affected by the number of synchronous auditory beeps. Audio-visual integration could appear to cross-modal perceptual organization. On the other hand, intra-modal perceptual organization has been reported to influence audio-visual perception. Therefore, the present study examined preliminarily the effects of intra-modal perceptual organization on fission and fusion illusions. In experiment, visual target was presented simultaneously with auditory beep and visual inducer. The results indicated that the occurrence of fission illusion inhibited when the number of presented beeps and inducers was incongruent. On the other hand, the occurrence of fusion illusion was not affected when the number of presented beeps and inducers was different. Therefore, intra-modal perceptual organization would affect to fission and fusion illusions in the different fashion.
