How people with synaesthesia can hear colours
We all know that human beings are born with five senses that have five specific functions. Eyes are for seeing, ears for hearing, noses for smelling, tongue are for tasting and skin is for feeling. But there are some people whose senses are intertwined. They perceive the world with an added dimension. They may be listening to music and seeing colours produced from those sounds or hear sounds that they associate with bright colours. Maybe they can taste flavours on their tongue but connect them with a visual. This linking of different senses is known as synaesthesia.
Synaesthesia: What is it all about?
Synaesthesia is a neurological condition in which sensory information meant to stimulate one of the senses stimulates several other senses. People who have synaesthesia are called synaesthetes. The word synaesthesia comes from the Greek words: synth which means “together” and aesthesia which means “perception”. Research indicates that synaesthesia is usually a genetic condition and people are either born with it or develop it in early childhood. However, there is a possibility for it to develop later in life. There is no treatment for synaesthesia.
How does it work?
The five senses may seem separate from one another, but in the end, it is our brain that processes all the input received through our sensory organs. These organs send an electrical signal to our brains through our nervous system, much like a current down a live wire. They light up different parts of our brain like the primary visual cortex for when you see a bright yellow colour. For people who have synaesthesia, these signals stimulate more than one part of the brain. So, seeing yellow will not only stimulate the primary visual cortex, but also their parietal lobe, which tells us what something tastes like. It’s like their wires are interconnected.
Types of synaesthesia
Synaesthesia can occur between almost any two senses. There has even been one synaesthete, Solomon Shereshevsky, who experienced synaesthesia that linked all five senses. Some of the common types of synaesthesia are listed below.
- Chromesthesia: Association of sounds with colours
- Grapheme-colour synaesthesia: The connection of letters and days of the week with colours
- Misophonia: Negative experiences (anger, fright, hatred, disgust) triggered by specific sounds
- Lexical-gustatory synaesthesia: The association of certain tastes with words
- Auditory-tactile synaesthesia: The condition in which certain sounds induce sensations in parts of the body
- Mirror-touch synaesthesia: This occurs when individuals feel the same sensation that they see in another person
- Spatial sequence synaesthesia: Numerical sequences perceived as points in space
- Ordinal linguistic personification: Ordered sequences, such as ordinal numbers, week-day names, months, and alphabetical letters associated with personalities or genders