What is synesthesia?

Why can some people see the colour of music or taste the flavour of words?

brain photo

Synesthesia is a condition that affects around four per cent of the global population, and enables them to experience the world in a different way. During our infant development,the connections in our brains are held close together; areas in the brain that control taste, hearing, sight, smell, and touch are overlapped.

As we grow into adults those connections are pruned apart, but it is thought this process is interrupted somewhat for those with synesthesia. There have been over 60 forms of synesthesia reported, one of the most common being ‘grapheme-colour’ synesthesia. People with this type of the condition see colours in association with letters and numbers. However, there is no standard for this association; not every ‘A’ is red for everyone with the condition. This blending of sensory information extends to other senses, such as seeing the colour of sound. One participant in a study of lexicalgustatory synesthesia (the ability to taste words) said they tasted Dutch chocolate when shown an image of a phonograph.

Those with number form synesthesia see numbers in physical space in varying forms and shapes. Many synesthetes may have more than one type of synesthesia, and quite often people aren’t even aware they have the condition. So ask yourself, how do you see the alphabet, and what colour is it?


For more information about science and technology, visit our website now. If you have a tablet or smartphone, you can also download the latest digital version onto your iOS or Android device. To make sure you never miss an issue of How It Works magazine, subscribe today!