A savant is a person with a remarkable memory, brain dysfunction, and compensation in the right hemisphere of the brain. Scientists believe that savant skills stem from compensation for this brain dysfunction.
Between 50-75% of all savants are believed to be on the Autism Spectrum; between 10-37% of people on the Autism Spectrum are believed to have one or more savant skills.
There are three types of savants: prodigies, talented savants, and savants with splinter skills. Very, very few savants are prodigies; it is estimated that there are no more than 50 alive at any given time. Many more have splinter skills, such as calendar calculation (instantly knowing the day of the week for any date in history), lightening calculation (instantly solving complex math problems), or memorizing baseball statistics or train schedules. The rest are talented, but are not prodigies.
Contrary to popular belief, people with normal or even high intelligence can have savant skills. Savants can either be born with their ability, or acquire it later in life due to brain damage, which can be due to a brain injury, or due to a disease such as frontotemporal dementia. (Most people with brain injuries do not acquire savant skills, so please don't try to awaken your latent savant abilities by hurting yourself!)
Now, to the question, am I a music savant? It's really hard to say. I have been diagnosed as having neurocognitive dysfunction of the right temporal lobe, and neuropsychological testing also revealed that I have compensation in my right hemisphere, so I do have the basic neurological groundwork for a savant skill to emerge.
I also have a very remarkable memory, similar to a person with hyperthymesic syndrome (very superior autobiographical memory), with excellent memorization ability (I was in every play in high school, and I was feeding all the other actors their lines by the third rehearsal, even though I never read the script outside of play practice). However, I have a huge deficit in the type of memory called working memory (which is a person's memory for what they are saying, thinking, or doing). All prodigious savants have an extremely good working memory.
There are around 100 documented prodigious savants in all of time. I am not one of these. It's as if I had the seeds for it, but they fell on poor soil.
I might be a talented savant. My neurology and my musical ability seem to line up with that possibility.
As a preschool aged child, I taught myself to play melodies by ear within a few days, and I didn't distinguish between existing songs and new songs in my head. At the time, it never occurred to me that I was doing anything unusual. I thought that any child my age would do exactly the same thing if someone gave them a keyboard to play with.
Even though I had been taking piano lessons for years and had already written sheet music, my grade school band teacher told my parents that I could not be taught to play a musical instrument. At the time, we just thought he was a bad teacher, but in retrospect, maybe he was right. My piano teacher did say that I learned differently from all his other students, except for one (although that could just as easily be explained by a learning disability, or by both of us learning to play by ear before we learned to read music).
At piano recitals, parents of other children that I didn't even know used to snap my photo while I was playing. I don't know why; either they wanted to capture the experience on film (despite not bringing a camcorder with them), or they thought I'd be famous someday. They certainly weren't taking the photos to give copies to my parents, since we never got copies of any of them.
When I string memories like these together, I have to wonder, am I a savant? I don't suppose I'll ever know for certain. There is no test for Savant Syndrome.