Synesthesia: This sensory disorder allows you to 'see' sounds

What do you see when listening to music with your eyes closed? Do you start to see shapes appear, or maybe different colours depending on the note? If you answered yes, then you may be like Stevie Wonder, Lady Gaga and Pharrell Williams, who all have synesthesia. Don’t worry it isn’t a disease.

Coloured grapheme synesthesia

I'll never forget it, I was about 7 years old, I closed my eyes and that's how it started. I started to see sounds. Wow!

This is how Pharrell Williams describes what he felt when he first started mixing his senses for the first time. This phenomenon is called synesthesia.

Synesthesia can come in different forms, close to 150. For example, a person who has synesthesia might be able to ‘taste’ sounds or attribute a number to colour, the latter is called coloured grapheme synesthesia.

What causes synesthesia?

The cause of synesthesia is still unknown. However, in 2017, Robert Foekemke, a neuroscientist at NYE Langone Health told LiveScience that it could be due to a high correlation between visual signals and the physical sensation of sounds. To illustrate this, the GIF below is used. Froemke explains that since we can see a heavy tower hit the ground and the image trembles, you are expecting to hear a sound, well, for some, they actually that sound.

But what about those that don’t hear anything? According to Christopher Fassnidge, a doctoral student that specializes in synesthesia at the University of London, it could be due to an inhibition of the brain to create a connection between different sensory regions. These connections are possible for those that heard the sound.

Read more:

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⋙ Optical Illusion: Can you read all the numbers in this image?

⋙ Schizophrenia: New discovery lifts the veil on the origins of the disorder

It affects only a small percentage of the population

Synesthesia is a rare phenomenon and only affect between 2 and 4% of the population. However, these numbers aren’t the most reliable as it is possible that people who have synesthesia aren’t aware of it as they believe those around them process the world the same way as them.

Either way, synesthesia isn’t a disease. The artist Wassily Kandinsky used his synesthesia to paint sounds! One of the most well-known cases of synesthesia is the rat that has an aptitude for fine dining.