A vivid perception of color is evoked by spoken words (“seven” is blue, for instance) in people with a condition called ‘colored-hearing synesthesia’. This perception is associated with activity in an area of the brain that responds to color vision, reports a paper in the April issue of Nature Neuroscience. Because other visual areas are not activated, these results suggest that a conscious perception of color can be created by activation of the brain’s ‘color center’ alone.
Synesthesia runs in families, suggesting that it may have a genetic basis, and it is strongly sex-linked, being six times more common in women. In the current study, people who do not have synesthesia did not show activity in the color center in response to spoken words, even after they had been extensively trained to visualize particular colors in association with certain words. The authors conclude that synesthesia is much more like a color hallucination than color imagery, and that it may result from developmental errors in the formation or retraction of connections between auditory cortex and visual cortex.
Dr. Jeffrey Gray
Department of Psychology
Institute of Psychiatry
Tel: +1 650 321 2052, ext. 234 (currently at the Center for Advanced Studies in Behavioral Science at Stanford)
(C) Nature Neuroscience press release.
Message posted by: Trevor M. D'Souza