Sound-Color Associations in Psychosis-Prone Individuals

Synesthetic-pseudosynesthetic characteristics have been hypothesized to be a schizophrenia endophenotype, a developmental feature, and/or a symptom of psychosis. Few studies to date, however, have examined whether individuals at risk for psychosis have synesthetic symptoms. We examined the relationship between hue and pitch in high psychosis prone (HP; n = 30) and low psychosis prone individuals (LP; n = 31). Synesthesia was evaluated using self-report and two performance-based tasks. Results revealed that HP subjects experienced more synesthetic experiences than the LP only on the self-report measure. These results suggest that high psychotic prone patients report unusual experiences but are no more likely to exhibit synesthesia than LP individuals. HP individuals, however, were more likely to choose shorter wavelength colors than LP individuals on performance tasks. These results are consistent with the notion that psychosis vulnerability is associated with a preference to light wavelengths associated with increasing emotional valence and negative affect.