Synesthesia is an unusual neurological condition in which the senses get mixed up with each other. For a few people, the stimulation of one sensory pathway leads to the stimulation of another, just as when you pluck one string on a guitar, another vibrates sympathetically. As a result, synesthetes can 'see' words (they literally see certain shapes or colours when they hear or pronounce certain words), 'hear' texture, feel that certain concepts are further away in space than others (1980 is further away than 1990), and so on. The emphasis and intensity of the condition varies from person to person. One of the striking things about it is that because synesthetes grow up like this, they assume, often until quite late in life, that everyone else experiences the world in the same way.
It's a fascinating phenomenon, and today I came across an amazing interview with a man called James Wannerton who has particularly acute and specific form of synesthesia: he tastes sounds, particularly words. One of his first memories of the sensation is from primary school:
I have very strong memories of sitting in assemblies. We were read the Lord’s prayer every morning: it had a taste of very thin crispy bacon.
Talking about it now, can you taste it?
Yeah. It’s quite strong as well.
Can you describe synesthesia?
It’s not an extra sense, but it does give me an extra perception. It’s like getting an eye-dropper of taste dripped on my tongue. I get a taste, temperature and texture. One of the ways I stop this affecting my concentration on a day-to-day basis is to eat strong-tasting sweets like Wine Gums, and drinking coffee.
Do you ever synesthetically taste something you’ve never eaten before?
It can be difficult to articulate a particular sensation and compare it to a foodstuff. These things are specific and very, very complex. When I’ve taken part in research, I could write maybe half a page of A4 on a particular word’s effects. Ever since I was young, I had a taste for the word ‘expect’ and I could never quite put my finger on what it was. One day, I bought a packet of Marmite-flavoured crisps. When I had one, it clicked – that’s the taste of “expect”! If I had to describe it I’d say it’s a bit tangy, slightly thick but crunchy. I get lots of metallic tastes that I can’t describe, other than saying it’s smooth or rough. The name David gives me a very strong taste of cloth, a bit like sucking on a sleeve.
He used to choose friends and even girlfriends on the basis of whether their name tasted nice or not. It's as good a rationale as any, I suppose.