Synesthesia is a neurological phenomenon in which information meant to stimulate one sense stimulates additional senses, as well.
This article covers the different types of synesthesia.
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What Is Synesthesia Like?
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Synesthesia is essentially the merging of multiple senses.
It is not a disorder, but rather a way of perceiving the world.
Not everyone experiences synesthesia the same way since synesthesia depends on which senses are paired.
It is estimated about 1% of the general population has this throw in of synesthesia.
For the most part, people report that these sensations are experienced internally, in their mind.
Who Gets Synesthesia?
Synesthesia has been described as a neurodevelopmental condition.
Synesthesia can be:
Synesthesia is also associated with higher rates of certain mental health conditions and traits.
This includes:
Is Synesthesia a Form of Autism?
No, synesthesia is not a form of autism.
A 2023 twin study found that there is a genetic link between autism and synesthesia.
Both synesthesia and autism are examples of neurodivergence.
What Causes Synesthesia?
Scientists do not agree on the exact cause of synesthesia.
In adulthood, those with synesthesia have hyperconnectivity of neurons in the sensory areas of the brain.
Some researchers argue that synesthesia is, in part, a learned skill leftover from childhood.
Types of synesthesia include:
This is not a complete list of all types of synesthesia.
Synesthesia Testing
It is challenging to test synesthesia because each person’s experience is very individual.
The Synesthesia Battery is one validated test for grapheme-color synesthesia.
Tests for synesthesia, including the Synesthesia Battery, can be taken online.
Consistency Test for Synesthesia
The consistency test looks for grapheme-color synesthesia.
This test is done multiple times over weeks, months, or years.
A test positive for synesthesia would have consistent answers over time.
How Is Synesthesia Treated?
Synesthesia is not a mental illness.
Treatment for synesthesia does not yet exist.
Long-Term Outlook for People With Synesthesia
Most people with synesthesia are able to live a normal life.
Summary
Synesthesia is the merging of senses.
There are many types of synesthesia.
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