This pathway is nearly always unidirectional and, in this case, the same auditory stimulus will result in the same color perception consistent throughout years of the synesthetes' life. This mechanisms underlying the symptoms of synesthesia become increasingly more complicated as one delves deeper into the synesthete realm: synesthesia may result in a paired perception (in the above example, audio may trigger both a color and an olfactory perception) and many synesthetes express more than one type of synesthesia, such as color-to-audio and number-to-personality (Cytowic et al., 2009). In addition, synesthetic perceptions are completely different for every person and each type of synesthesia can result …show more content…
Pythagorus was not diagnosed with synesthesia in his time and his relationship with numbers was generally taken as a personal idiosyncrasy, yet the accounts of his perception of numbers undoubtably points to synesthesia. Mentions of synesthesia in literature are few and far between for the next two thousand years or so, and it was not until the nineteenth century that synesthesia began to be investigated further. Sir Francis Galton was the first to write a professional paper on synesthesia in 1880, where he noted the peculiarity of some people to have a more intuitive sense of association between separate sensory systems and proposed that synesthesia had a genetic basis. Unfortunately, the ascent of behaviorism as the principal school of thought in psychology during the twentieth century dismissed the concept of synesthesia, as it is not something that is observable in behaviors, but rather manifests itself in an individual’s consciousness (Ramachandran et al.,