In the classic film, Cruise discovers that he has a brother, Hoffman, who suffers from autistic disorder, and is unable to care for himself.
Cruise travels across the country to take his brother home with him, only to be continually baffled, annoyed, and sometimes enraged at the oddness and specificity of his demands.
But along the way, Cruise also realizes his brother's tremendous gift: He is a savant.
He can do high level math problems in his head with no processing time.
His mind operates more quickly than Cruise ever thought possible.
For a while, Cruise even profiteers from that gift by taking his brother, who he discovers can count cards like nobody's business, into a Vegas casino.
It is probably that scene more than any other that intrigued so many people about autism.
What kind of potential and power is locked within the human mind? And isn't it cool that autistic people can do such amazing things! The reality is somewhat less sexy.
An autistic person has, as Dr.
Temple Grandin puts it, different wiring in their brains.
They may have tripple the bandwidth in one category--math, for instance, is a common one--but that bandwidth comes the expense of normal functioning centers in the brain.
Grandin insists that Albert Einstein would certainly have been diagnosed with Autism had the experts been around in his day.
That would explain how the greatest mind of the twentieth century could, as legend tells, remember to go to a party but forget to wear his pants: all the wires were going to the technical math and science centers of his brain.
His mind had no time for fashion.
While there are many savants who are autistic, most autistic children do not come with flashy gifts for card counting or music or painting.
And even if they did, it would be little relief for their parents.
Cool gifts are cool, and world class gifts are world class cool.
But what parent wouldn't trade in even the most phenomenal mental powers for a real conversation with their autistic child? Yes, autism is a fascinating study for many people.
But for these parents, it is less interesting, and it's not a study.
It's a person.
They don't want a Rain Man.
They just want to know their son.