This is my post on synesthesia (sin-ess-thee-zha) The zh sound in my pronunciation guide is that of the g in mirage or the z in azure. I only recently heard of this condition and wanted to write about what I learned. “Synesthesia” is the condition. A “synesthete” is the person having the condition.
It occurs in about 1 out of 2,000 people or 1 out of 10,000 depending on whose statistics you are reading. It is a condition that I would liken to color-blindness except the effect is almost opposite to being color-blind. (I don’t have this condition so I am not speaking firsthand here.)
What happens is this: a synesthete gets extra senses when seeing something or feeling or smelling something (or any of the 5).
They may be able to see a color when music plays, or taste something when they see a certain shape. Many synesthetes see letters and numbers in colors other than the color they are printed in. These phenomena are always the same for them. If the letter K is blue, it will always be blue. It is also individual. Someone else may see K as orange all the time. And every synesthete will get different perceptions in different amounts for one or many senses.
Like color blindness it is not a disease and cannot be caught or transmitted as such. It can run in families though the mechanism isn’t as clear cut as color-blindness. These senses are NOT delusions or an overactive imagination or a mental disorder. It is just an extra function of the person’s brain similar to the way color blindness is one less function.
Sometimes a person will not realize they are a synesthete for many years because they assume everyone gets the same extra senses they get. After all, I never question the way I sense things.
I got some of my information from a textbook and some from online sources. Here is a website with information and links:
http://www.bu.edu/neuropsychology/synvc.html
Hopefully I have explained it well enough for being a non-synesthete. I posted this info on Muppet Central in nearly identical wording before and wanted to also post it here. Most people I run into have never heard of it before so I am usually teaching them. If you know I am not explaining parts of it right please correct me.