Consistency and strength of grapheme-color associations are separable aspects of synesthetic experience

• Authors: Simon Lacey, Emory University; Margaret Martinez, Emory University; Nicole Steiner, Emory University; Lynne Nygaard, Emory University; Krishnankutty Sathian, Emory University
• Journal Title: CONSCIOUSNESS AND COGNITION
• Volume: Volume 91
• Publisher: ACADEMIC PRESS INC ELSEVIER SCIENCE | 2021-04-29, Pages 103137-103137
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1016/j.concog.2021.103137
• Subjects: Health Sciences, Medicine and Surgery
• Keywords: Social Sciences; Psychology, Experimental; Psychology; Synesthesia; Grapheme; Color; Implicit Association Test; STANDARDIZED TEST BATTERY; INDIVIDUAL-DIFFERENCES; STROOP-LIKE; SYNAESTHESIA; SPACE; CONNECTIONS; SENSITIVITY; COMMON

Abstract

Consistency of synesthetic associations over time is a widely used test of synesthesia. Since many studies suggest that consistency is not a completely reliable feature, we compared the consistency and strength of synesthetes’ grapheme-color associations. Consistency was measured by scores on the Synesthesia Battery and by the Euclidean distance in color space for the specific graphemes tested for each participant. Strength was measured by congruency magnitudes on the Implicit Association Test. The strength of associations was substantially greater for synesthetes than non-synesthetes, suggesting that this is a novel, objective marker of synesthesia. Although, intuitively, strong associations should also be consistent, consistency and strength were uncorrelated, indicating that they are likely independent, at least for grapheme-color synesthesia. These findings have implications for our understanding of synesthesia and for estimates of its prevalence since synesthetes who experience strong, but inconsistent, associations may not be identified by tests that focus solely on consistency.