Colored-Speech Synaesthesia Is Triggered by Multisensory, Not Unisensory, Perception

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1467-9280.2009.02338.x Byline: Gary Bargary (1,2,3), Kylie J. Barnett (1,2,3), Kevin J. Mitchell (2,3), Fiona N. Newell (1,2) Abstract: ABSTRACT Although it is estimated that as many as 4% of people experience some form of enhanced cross talk between (or within) the senses, known as synaesthesia, very little is understood about the level of information processing required to induce a synaesthetic experience. In work presented here, we used a well-known multisensory illusion called the McGurk effect to show that synaesthesia is driven by late, perceptual processing, rather than early, unisensory processing. Specifically, we tested 9 linguistic-color synaesthetes and found that the colors induced by spoken words are related to what is perceived (i.e., the illusory combination of audio and visual inputs) and not to the auditory component alone. Our findings indicate that color-speech synaesthesia is triggered only when a significant amount of information processing has occurred and that early sensory activation is not directly linked to the synaesthetic experience. Author Affiliation: (1)School of Psychology (2)Institute of Neuroscience, and (3)Smurfit Institute of Genetics, Trinity College Dublin Article History: (R eceived 8/8/08; R evision accepted 11/8/08) Article note: Address correspondence to Fiona N. Newell, Institute of Neuroscience, Lloyd Building, Trinity College, Dublin 2, Ireland, e-mail: fiona.newell@tcd.ie.