Abstract
Although synaesthesia has been linked to increased creativity and engagement with the arts, most of the evidence has come from visual arts rather than music. Here we show for the first time that synaesthesia is far more prevalent in musicians than non-musicians (an odds ratio of about 4). We show that this result holds true for all three different kinds of synaesthesia that we considered (grapheme-colour, sequence-space, sound-colour) including for types of synaesthesia unrelated to music. That is, it is not simply the case that the ability to 'see' music drives the higher prevalence, although this may have a role. Instead, we speculate that the cognitive profile of synaesthetes is conducive to musicality. We provide an estimate of the prevalence of sound-colour synaesthesia in non-musicians of between 0.3% and 1.3%, depending on the threshold applied, with comparable figures for musicians of 1.3% to 7.3%.