A recent NY Times article, Savant for a Day, reports on a hard-to-believe invention:
The Medtronic was originally developed as a tool for brain surgery: by stimulating or slowing down specific regions of the brain, it allowed doctors to monitor the effects of surgery in real time. But it also produced, they noted, strange and unexpected effects on patients’ mental functions: one minute they would lose the ability to speak, another minute they would speak easily but would make odd linguistic errors and so on. A number of researchers started to look into the possibilities, but one in particular intrigued Snyder: that people undergoing transcranial magnetic stimulation, or TMS, could suddenly exhibit savant intelligence — those isolated pockets of geniuslike mental ability that most often appear in autistic people.
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He has used TMS dozens of times on university students, measuring its effect on their ability to draw, to proofread and to perform difficult mathematical functions like identifying prime numbers by sight. Hooked up to the machine, 40 percent of test subjects exhibited extraordinary, and newfound, mental skills. That Snyder was able to induce these remarkable feats in a controlled, repeatable experiment is more than just a great party trick; it’s a breakthrough that may lead to a revolution in the way we understand the limits of our own intelligence — and the functioning of the human brain in general.
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Perhaps the most famous savant was Dustin Hoffman’s character in ”Rain Man,” who could count hundreds of matchsticks at a glance. But the truth has often been even stranger: one celebrated savant in turn-of-the-century Vienna could calculate the day of the week for every date since the birth of Christ. Other savants can speak dozens of languages without formally studying any of them or can reproduce music at the piano after only a single hearing. A savant studied by the English doctor J. Langdon Down in 1887 had memorized every page of Gibbon’s ”Decline and Fall of the Roman Empire.” At the beginning of the 19th century, the splendidly named Gottfried Mind became famous all over Europe for the amazing pictures he drew of cats.