Can you train yourself to stop synaesthesia?

Duncan:: That's an interesting point. I think it's definitely possible to kind of modify your experiences. There's anecdotal evidence to suggest that this kind of strength of the synaesthetic experience does fade over time. It's commonly thought to be a kind of developmental thing. So, there is evidence that it changes over the course of a lifespan, but I think it is possible to kind of actively modify what you do experience; i mean the brain is incredibly plastic. There is an anecdotal report from a synaesthete who used mathematics as part of his job and everyday life, and he found that having coloured numbers was a very good benefit for his work whereas coloured letters didn't really seem to kind of lend any advantage. And over the course of time, the strength of his associations with colour and letters tend to fade away. So, I think it is possible to modify experience. I'm not entirely sure if you could get rid of it entirely.

Barry:: There's some work coming out of Roi Cohen Kadosh's lab in Oxford suggesting that, under hypnosis, synaesthesia, or the experience of the extrasensory phenomenon, disappears. So, is it possible to induce it under hypnosis too? And we know that hypnosis is something that you're either susceptible to or not genetically. So, there is a limited class of people who could turn it off.