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Published on: February 20, 2014
Colours sometimes count: awareness and bidirectionality in grapheme-colour synaesthesia
Addie Johnson1, Marieke Jepma, Ritske de Jong
1University of Groningen, Groningen, The Netherlands. a.johnson@rug.nl
Quarterly Journal of Experimental Psychology (2006)
|September 14, 2007
Summary
Grapheme-colour synaesthesia can occur even without conscious awareness of the grapheme. This study also suggests synaesthesia may be bidirectional, with colours influencing grapheme processing.
Area of Science:
- Cognitive Neuroscience
- Psychology
Background:
- Grapheme-colour synaesthesia is a neurological phenomenon where individuals perceive specific colours associated with letters or numbers.
- Previous research has primarily focused on the unidirectional aspect of graphemes inducing colours.
Purpose of the Study:
- To investigate if conscious awareness of the grapheme is essential for colour induction in synaesthesia.
- To explore the potential bidirectionality of grapheme-colour synaesthesia, examining if colours can influence grapheme processing.
Main Methods:
- Employed attentional blink and Stroop paradigms with digit targets.
- Utilized 10 grapheme-colour synaesthetes and 10 matched controls in three experiments.
Main Results:
- Some synaesthetes reported experiencing synaesthetic colours even when unable to consciously identify the inducing grapheme.
- Congruency effects indicated that colours can influence grapheme processing, suggesting bidirectionality in some synaesthetes.
Conclusions:
- Conscious awareness of the grapheme is not always necessary for synaesthetic colour induction.
- Grapheme-colour synaesthesia demonstrates bidirectionality, with colours potentially influencing grapheme processing for some individuals.
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