I think one of the problems with the definition of autism is we keep expanding it. It started as "early infantile autism", and then it became "autism", and now it's "autism spectrum disorder". I'm not opposed to that from the standpoint of trying to broaden our vistas, and so forth. But from a research point of view, the term autism is lost in specificity.

The narrower we define autism, and the more strictly we control for particular behaviors, the more likely we are to find what I think are the subgroups of autism.

We have to be careful that we don't keep multiplying disorders and diluting them. I think there is a difference. People talk about Asperger's as high-functioning autism, which I think it is. But it does have some of its own characteristics, like the preservation of language, particularly, which may be right brain dysfunction instead of left brain dysfunction, and we lose something in that, as things lose their specificity, and we keep diluting things. I'm not sure that's helpful.

What happens is most of us are so busy in our lives with our families and our vocation which we should be, but we tend not to look at what I call these parallel interests, and they develop along the way. And sometimes one can say, well, you know, why should I grow my own garden and spend all that time when I can buy carrots cheaper at the supermarket and just put aside that kind of an interest.

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.

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.

With respect to why some acquired savants are musical, and some are good at the arts, and some are mathematical, why aren't they all the same; I think that has to do with this genetic endowment that all of us have.