Abstract
Humans’ enumeration processing shows a discontinuity between three or four items and larger numbers. Enumerative discrimination is fast and accurate for sets of up to three or four items, but suddenly becomes slow and error beyond this range. Each enumeration processing is named as subitizing for small quantities and counting for larger ones, respectively. We examined the effects of auditory stimulus on visual processing in multiple stages using this discontinuity of enumeration processing. The results indicated that pitch-elevation corresponding sound enhanced to enumerate five and six objects. Moreover, the capacity of subitizing was increased by pitch-elevation corresponding sound. Therefore, auditory stimulus facilitated enumeration processing in subitizing process and limited counting process. The present study suggests that audio-visual interaction occurs in multiple stages.
