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Colour-grapheme synesthesia affects binocular vision
Chris L E Paffen1, Maarten J van der Smagt, Tanja C W Nijboer
1Experimental Psychology, Helmholtz Institute, Utrecht University Utrecht, Netherlands.
Frontiers in Psychology
|November 11, 2011
Summary
Individuals with colour-grapheme synesthesia experience colors with achromatic graphemes. Synesthetic colors increase binocular rivalry, similar to normal visual processing.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Visual Perception
Background:
- Colour-grapheme synesthesia involves perceiving inherent colors in achromatic graphemes.
- Debate exists on whether synesthetic achromatic graphemes are processed similarly to chromatic graphemes.
Purpose of the Study:
- To investigate if synesthetic colour experiences in colour-grapheme synesthesia influence visual processing.
- To compare the impact of synesthesia-inducing graphemes versus non-inducing graphemes on binocular rivalry.
Main Methods:
- Utilized binocular rivalry, where dichoptically presented incompatible images compete for conscious perception.
- Compared the incidence of binocular rivalry for achromatic digits (inducing synesthesia) versus achromatic non-digits (not inducing synesthesia).
Main Results:
- Achromatic digits that induce synesthetic colour percepts significantly increased the incidence of binocular rivalry.
- Synesthesia-inducing digits promoted binocular rivalry over binocular fusion compared to non-digits.
Conclusions:
- Synesthetic colour experiences can create conditions that promote binocular rivalry.
- This suggests that synesthetic perception shares processing mechanisms with normal visual rivalry induction.
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