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Updated: Aug 8, 2026
10:27
Training Synesthetic Letter-color Associations by Reading in Color
Published on: February 20, 2014
Color congruity effect: where do colors and numbers interact in synesthesia?
Roi Cohen Kadosh1, Avishai Henik
1Department of Behavioral Sciences and Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel. roico@bgu.ac.il
Summary
Digit-color synesthesia impacts numerical judgments, affecting synesthetes differently than non-synesthetes. This study reveals how synesthetic experiences influence cognitive tasks involving number comparison.
Area of Science:
- Cognitive Psychology
- Neuroscience
- Synesthesia Research
Background:
- The size congruity paradigm demonstrates how physical properties interfere with numerical judgments.
- Synesthesia, specifically digit-color synesthesia, involves an automatic association between digits and colors.
Purpose of the Study:
- To investigate the influence of irrelevant colors on numerical magnitude comparison in a digit-color synesthete.
- To explore the interaction between synesthetic color associations and numerical processing.
Main Methods:
- A color congruity paradigm was used, replacing physical size with irrelevant colors.
- Performance of a digit-color synesthete (MM) and non-synesthetes was compared on numerical comparison tasks.
Main Results:
- The synesthete (MM) showed a congruity effect, being slower when colors deviated from her synesthetic experience.
- The impact of color on MM's judgments was modulated by numerical distance.
- Non-synesthetes' performance was unaffected by the irrelevant colors.
Conclusions:
- The interaction between colors and digits in synesthesia likely occurs at the conceptual level.
- The color congruity paradigm can help determine the stage of color-digit binding in synesthesia.
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