Intro to Synaesthesia

Musicians painting scenes, hearing unidentifiable colours, chefs feeling flavors and artists experiencing colours. These are not the effects of LSD, but symptoms of a nonthreatening neurological condition called Synaesthesia. Meaning "The combining of the senses", individuals with synaesthesia experience consistent confusion of sensory input. Why and how can this happen? Is this a muddling of sensory input, or the awareness of nonvisual information passing through the eyes? A person with Synasthesia may associate every number they see with a different colour, experience 'seeing' sound or tasting shapes. Cases of synaesthesia have been reported in psychology and medicine for over a hundred years yet little is understood about why the sensation may occur and apart from inheritance, how someone may be physiologically vulnerable to it. Also, to what extent are most of us synaestheic( do you understand what is meant bysharp cheese, a blue day or any popular metaphor??) Until recently scientists were unsure synaesthesics existed as the symptoms are largely subjective and there had been no scientific evidence or means to acquire data for a comprehensive study. The little understanding of synathesia leads to fewer possible means to investigate; most people who have symptoms of graphene synaesthesia,the most interesting to study colour-associated form, have held symptoms from a young age or denveloped them as an adolescent. In both cases they may learn early on that most adults wont believe them or they assume everyone has a similar experience with senses. As a result, many people will keep symptoms and their subsequent effect on perception to themselves. Now, neuroscientists recognize specific stimuli can induce it leading scientists to ideas for experimental methods to investigate this strange mingling of the senses. To describe this strange sensation, particularly the more common visual part of it, we will first have to explore the visual system in more detail.