Savant syndrome and autism, I think, are not disorders of brain structure, but they're disorders of brain function.

There are some cases that have come to my attention where there's been a head injury, or getting struck by lightning and surviving, with really no disability or residual. So there are cases that I'm aware of where there's been some incident which triggered the acquired savant ability, but is not associated with long term disability, so that can occur. But I think that's probably the exception rather than the rule in that I think many of the acquired savants do end up with some residual disability.

When I met my first savant in 1962, I was impressed by the abilities in these youngsters who had severe disabilities. They appeared to me to be islands of genius in the sea of disability. So I've maintained that word picture since that time, of these islands of genius that are so striking and so jarring when you see them, especially in people who have severe disability.

Now I realize, and I acknowledge, that the right brain/left brain distinction is a tremendous oversimplification. We don't come neatly divided into right and left hemispheres, but the fact is that the two hemispheres of the brain do specialize in certain functions.

The ways in which acquired savants show up are usually the same ways that congenital, or non-acquired, savant syndrome shows up. They tend to show up in the same areas: music, art, math, visual, spatial skills, and calendar calculating, although calendar calculating probably isn't quite as prominent in that group. They tend to show up quite quickly, or sort of explode on the scene and they then tend to have an obsessive sort of forceful quality about them in the same way as savant skills. So they tend to show up in the same ways.

A savant, by definition, is somebody who has a disability and, along with that disability, has some remarkable ability. Prodigies and geniuses have the remarkable abilities that the savant shows, but they do not have a disability. So, by definition, a savant includes someone with a disability, and a prodigy or genius are people who have these remarkable skills but they do not have a disability.

To some extent, we all have quirks or idiosyncrasies, and some geniuses, because of how bright they are and how focused they are, may have liberal eccentricities, but they're not at a disabling level.