Can you hear colours or taste words? If so, you are not alone. As many as four in every 100 people have linked senses or synesthesia. Experienced by Russian novelist Vladimir Nabokov, born this day in 1899, grapheme colour synesthesia [where numbers or letters evoke vivid colours] is the most common manifestation. The illustration shows how digits appear to one synesthete. When looking at numbers their brain shows activity in both the number and colour processing areas. And they appear to have an unusually high number of connections between these regions. Synesthesia seems to be mainly hereditary, determined by genes. One theory as to the potential evolutionary benefit of this trait is that it enhances creativity. The phenomenon is much more frequent among writers, artists and musicians. Such ability to quickly link colours and digits may also help memorise numerical strings.
Written by Sarah McLusky
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