Have you ever tasted a word? Seen colors when you listen to music? If that sounds familiar, you might be one of the roughly four percent of people who have synesthesia. can be a sense for some people in surprising ways.
Synesthesia — a neurological condition in which activating one sense, for example hearing, triggers another, usually unrelated, sense, for example sight. People who experience synesthesia are called synesthetes.
They differ from other people because they experience extra . A team of cognitive scientists led by Sophie Smith at the University of Sydney and Anina Rich at Macquarie University has spent a lot of time studying this rare trait.
What did researchers find about synesthesia?
Research shows synesthesia is more common in women, The Conversation reports. The condition also often runs in families.
There are many different kinds of synesthesia. For example, sound-to-color synesthesia happens when the brain colors sounds. Some synesthetes see colors when they read, hear, or even think about letters or numbers; that form is called grapheme-color synesthesia.
Another example is mirror-touch synesthesia, where a person feels touches on their own body when they see someone else being touched.
We all naturally combine information from different senses. For example, when we watch someone speak, the brain merges sight and sound to understand them better. In synesthesia, those sensory links are a bit different.
People with synesthesia don’t control the overlap of their . Instead, these spontaneous, vivid experiences usually stay stable over time. For example, if a person with grapheme-color synesthesia perceives the letter “A” as red today, they will most likely perceive it that way for many years.
Synesthesia is not a disease or a disorder. It does not harm people or reduce their , although some individuals may occasionally find it overwhelming—for instance, if they feel pain whenever they see a character on screen in pain.
Overall, this remarkable trait does not usually interfere with everyday life.
What causes synesthesia — extra brain wiring or different brain activity?
Scientists have proposed two main theories about the cause, as Science Alert explained.
- Synesthetes have more connections in the brain.
According to this cross-activation theory, people with synesthesia show more links between different brain areas. This pattern might occur because their brains did not prune unused connections during development. Synaptic pruning helps the brain work more efficiently and is part of normal growth.
That means in someone with grapheme-color synesthesia, the brain region that recognizes letters is directly connected to the region that processes color. When that person sees a letter, they experience it as a color.
- People with synesthesia show somewhat different brain activity.
The second idea is that synesthetes have the same neural wiring as others, but some connections are stronger or more active.
For example, when we see a gray picture of a banana, we think of bananas as usually yellow, and we can measure brain activity that reflects that expectation. People with grapheme-color synesthesia might do the same with letters: when they see black letters, their brains activate particular colors.
Put simply, the debate about why synesthesia occurs comes down to whether synesthetes have a different brain structure or whether they just use their brains in an alternative way.
Does synesthesia make you more creative?
Scientific data show synesthesia appears more often among people in creative professions.
A large study of Australian synesthetes found that about 24 percent of participants worked in creative fields.
One reason may be that synesthetes connect ideas and sensations in unusual ways. Studies show people with certain types of synesthesia have more vivid imaginations.
Overall, as Ms. Smith and Ms. Rich point out, synesthesia is a powerful window into how our brain perceives the world. It reminds us that perception is not fixed or universal. The brain actively shapes perception, and the result is often far more varied and richer than we expect.
Photo: Unsplash
