Hashiya / Poster

The "initial knowledge" about the correspondence of auditory-visual events in macaque infants.

Hashiya, K. ^*, Ishikawa, S.⁺, Fujita, K.⁺ & Tomonaga, M.^+
* University of Tokyo ⁺ Kyoto University

     The "initial knowledge" about the correspondence of auditory visual events in macaque infants. Development in perception of temporal correspondence of auditory and visual events was studied in macaque infants, with using the looking time procedure. The subjects were shown video images accompanied with sound. We compared the subjects' responses between the following two conditions. (1) Natural condition: a wooden box being knocked with a stick in a quasi random interval. The video image and the sound were temporally in concert. (2) Unnatural condition: the video image and the sound were the same as those in the natural condition but the video image and the sound were temporally out of concert. The subjects looked at the stimuli for longer duration in the natural condition than in the unnatural condition. In the unnatural condition, the subjects tended to change their gaze direction more frequently. Such tendencies were evident even in the 2-week old infants. These findings suggest that macaques possess the "initial knowledge" about the correspondence between auditory and visual events from quite early stages of development.