A team led by neuroscientist Simon Fisher at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands, has discovered that synesthesia may be the the result from hyperconnected neurons. Using a new technique, the team extracted 37 genes that predicted whether family members inherited synesthesia. Apparently there is no single "synesthesia gene" or a set of genes, but 6 of the variants they found were related to the development of connections between neurons known as axons, which are expressed in both the auditory and visual cortices of the brain during childhood development.
Previous brain imaging studies of synesthetes had suggested that they might have an abnormally high number of neuronal connections. The new research suggests that an unusually high degree of connectivity in certain brain regions might predispose people to have synesthesia.
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