Synesthesia is a neurological condition that causes the brain to process data in the form of several senses at once. For example, a person with synesthesia may hear sounds while also seeing them as colorful swirls. The condition isn’t fully understood, but it is thought to be genetic and it affects more women than men
Types
The word “synesthesia” comes from the Greek phrase for “to perceive together”
- Most people with the condition experience at least two types of synesthesia
- grapheme-color synesthesia: letters or numbers seem to be colored on the written page or visualized as colored in the mind
- Other types include: smelling certain scents when hearing certain sounds, seeing music as colors in the air, tasting words, feeling that certain textures cause certain emotions, seeing a certain color when feeling pain
Causes
There are several competing theories about its causes
- One is that synesthesia results from an overabundance of neural connections
- Another theory is that everyone has these connections, but not everyone uses them
- A 2017 survey of 11,000 college students found that children who grew up hearing and speaking two languages starting at a very young age were more likely to have synesthesia than people who did not
- The source of the perceptions in people with synesthesia may be the way they associate certain sounds they hear with mental images that represent those sounds or whether the source was something completely different
Diagnosis
There is no official method of diagnosing synesthesia.
- Guidelines that were developed by leading synesthesia researcher Dr. Richard Cytowic include the following: Involuntarily experience their perceptions, project sensations outside the mind, have a perception that is the same each time, remember the secondary synesthetic perception better than the primary, have emotional reactions such as pleasurable feelings
