Does Attentional Processes Modulate Bimodal Interference in V-EAR Synaesthesia?

Abstract: Even though the prevalence of synaesthetic-like ‘Visually-Evoked Auditory Responses’ (V-EAR) in the general population is probably immense by all standards, it is hardly ever mentioned in the literature on general synaesthetic phenomena. We decided to try to reproduce earlier findings that about 1/5 experience motion-conjured sound percepts. We did so with a good margin (27% of our participants claimed to ‘hear’ motion). We were also interested in whether these V-EAR experiencers would show of the enhanced visual sequence discrimination capabilities reported in two earlier studies. This finding was not successfully replicated. Neither could we manage to find any intuitively reasonable connections between V-EAR, attention processes and destructive interference between incongruently sequenced bimodal stimuli. Instead, we found evidence of constructive interference between incongruently sequenced bimodal stimuli, something that might be due to the ‘auditory driving’ effect. We discuss these findings within the theoretical frameworks as proposed by earlier research on ‘classic’ synaesthesia.