Synesthesia, Imagery, and Performance

Synaesthesia, imagery and performance. Some types of synaesthesia are often described as a type of mental imagery. This chapter summarises research on the relationship of normal visuospatial imagery to grapheme-colour and sequence-space synaesthesia. Evidence is discussed that these synaesthesias are associated with stronger everyday visual imagery experience, above-average visuospatial skills, and greater tendency to adopt visuospatial strategies. This association is a potentially important methodological confound when synaesthetes' behaviour is compared with non-synaesthetes. I argue that standard imagery processes may be necessary and sometimes even sufficient for some varieties of synaesthesia. I also discuss how the character, individual differences and behavioural correlates of synaesthetic experience are informed by knowledge of distinctions within standard imagery, including spatial reference frames, visual versus spatial imagery, and types of image transformation. Evidence that imagery can act as a synaesthetic inducer is then considered. It is concluded that processes of normal imagery provide explanatory continuity between normal cognition and aspects of synaesthetic experience.