Do synesthetes have a general advantage in visual search and episodic memory? A case for group studies.
BACKGROUND
Some studies, most of them case-reports, suggest that synesthetes have an advantage in visual search and episodic memory tasks. The goal of this study was to examine this hypothesis in a group study.


RESULTS
In the present study, we tested thirteen grapheme-color synesthetes and we compared their performance on a visual search task and a memory test to an age-, handedness-, education-, and gender-matched control group. The results showed no significant group differences (all relevant ps>.50). For the visual search task effect sizes indicated a small advantage for synesthetes (Cohen's d between .19 and .32). No such advantage was found for episodic memory (Cohen's d<.05).


CONCLUSIONS
The results indicate that synesthesia per se does not seem to lead to a strong performance advantage. Rather, the superior performance of synesthetes observed in some case-report studies may be due to individual differences, to a selection bias or to a strategic use of synesthesia as a mnemonic. In order to establish universal effects of synesthesia on cognition single-case studies must be complemented by group studies.
Department of Psychology, University of Bern, Bern, Switzerland.
Nicolas
N
Rothen
Beat
B
Meier
D000367:Age Factors; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory