Sound enhances visual detection of illusory contour in infants
Poster Presentation

Yuji Wada
Food Function Division, National Food Research Institute

Nobu Shirai
Department of Psychology, Chuo University and Japan Society for the Promotion of Science

Yumiko Otsuka
Department of Psychology, Chuo University and Japan Society for the Promotion of Science

Ippeita Dan
Food Function Division, National Food Research Institute

Kaoru Kohyama
Food Function Division, National Food Research Institute

Akira Midorikawa
Department of Psychology, Chuo University

So Kanazawa
Department of Psychology, Shukutoku University

Masami K. Yamaguchi
Department of Psychology, Chuo University

     Abstract ID Number: 73
     Full text: Not available
     Last modified: March 19, 2007
     Presentation date: 07/06/2007 10:00 AM in Quad Maclauren Hall
     (View Schedule)

Abstract
In adult, a salient tone embedded in a sequence of insalient tones improves detection of a synchronously presented brief visual target in rapid visual distracting sequence. This phenomenon indicates that our perception for one sensory modality can be influenced by another modality, even when the latter modality provides no information about the judged property itself. However, no study determined when this kind of cross-modal enhancement emerges in infants. We conducted an experiment in which we used a preferential looking technique to determine whether the audio-visual enhancement might emerge early development. In the Experiment, we tested whether 5, 6, and 7 month old infants' preference of illusory contours over non-illusory figures which are organized of identical set of pacmen is enhanced by concurrent unique sound. Consistent with audio-visual enhancement, 7 month old, but not 5 and 6 month old, infants' preference of illusory contour was enhanced by salient sound. This result indicated that audio-visual enhancement in visual target detection is emerged at 7 month of age. Since illusory contours are typical percept produced by the function of visual cortex, this phenomenon shows emergence of functional integration among differentiated cortical areas rather than undifferentiated cortex.
Acknowledgement: We appreciate support from Advanced Research Laboratory, Hitachi Ltd.