Nature reports on a recently discovered form of synaesthesia where affected individuals actually feel a sensation when they observe someone else being touched.
Synaesthesia is a condition where senses become crossed, so people might seeing colours when they encounter numbers, or tastes when they hear certain words.
This new form of synaesthesia was found by accident, during a talk by neuropsychologist Dr Jamie Ward:
“We first came across the mirror-touch synaesthesia by chance,” says Ward. The sensation of touch was being discussed at a UCL neuroscience seminar, and someone suggested, as a thought experiment, imagining that people felt what they saw. A colleague of Ward’s objected, vigorously insisting that everyone does, in fact, feel what they see. It was the first time Ward had realised such a condition could exist.
“There may be a lot of such people around, since they are unaware that that they have the condition. They think it is normal,” says Ward. When he started to look for people who experience mirror-touch synaesthesia, he had little trouble finding them, he says.
Ward collaborated with Michael Bannisy to study the condition and they found that they affected people were more likely to confuse an observed touch with a real touch than unaffected people under experimental conditions.
They also found that people with the condition were especially sensitive to other people’s emotions, rating much higher on measures of emotional empathy.
The study is published in Nature Neuroscience but I’ve just discovered there’s also a great write-up over at The Neurophilosopher.