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Updated: Aug 12, 2026

Training Synesthetic Letter-color Associations by Reading in Color
Published on: February 20, 2014
When a line is a number: color yields magnitude information in a digit-color synesthete
1Department of Behavioral Sciences and Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev P.O.B. 653, Beer-Sheva, 84105 Israel. roico@bgu.ac.il
Abstract:
The phenomenon of synesthesia has received a great deal of interest recently in the scientific literature. Many previous studies stressed the unidirectional nature of this phenomenon. For example, color-grapheme synesthetes automatically perceive achromatic numbers as colored (e.g. 7 is turquoise). Conversely, colors do not automatically give rise to any sort of number experience (e.g. turquoise is 7). In contrast to the common view, we report on a digit-color synesthete in whom colors can evoke numerical representations in the absence of any digit presentation. It is concluded that in synesthesia there is a reciprocal rather than unidirectional flow of information between dimensions.
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