May 17, 2012
Brain injuries can sometimes reveal extraordinary talents in people. Now, savant syndrome is helping to create whole new fields of scientific discovery.
For a long time, it was a mystery as to how horses galloped. Did all four hooves at some point leave the ground? Or was one hoof always planted? It wasn't until the 1880s when a British photographer named Eadweard Muybridge settled the debate with a series of photographs of a horse in midstride. Muybridge took a great interest in capturing the minute details of bodies in motion. The images made him famous.
Muybridge could be obsessive -- and eccentric, too. His erratic behavior was blamed on a head injury he'd sustained in a serious stagecoach accident that killed one passenger and wounded all the rest. Now, researchers believe that the crash, which gave Muybridge a permanent brain injury, may actually have been partially responsible for endowing him with his artistic brilliance.
Muybridge may have been what psychiatrists call an acquired savant, somebody with extraordinary talent but who wasn't born with it and who didn't learn the skills from someplace else later. In fact, Muybridge's savant abilities had evidently been buried deep in the recesses of his mind the whole time, and the stagecoach incident had simply unlocked them.
It sounds crazy. But Muybridge is actually one of a number of people who've miraculously developed artistic, musical, or mathematical abilities as a result of a brain injury. There's Orlando Serrell, who was struck in the head with a baseball as a 10-year-old and found he could remember the weather for each day following his accident. There's Derek Amato, who woke up after hitting his head at the bottom of a pool and became a master pianist at 40, despite lacking any sort of musical training. There's Alonzo Clemens, whose verbal and cognitive abilities stopped developing at the age of three due to a head injury but who can assemble incredibly detailed sculptures of animals in a matter of minutes.
Wisconsin psychiatrist Darold Treffert keeps a registry of known savants as part of his research on the subject. Savants are extremely rare to begin with, he said in a phone interview. Acquired savants are rarer still. Of the 330 savants from around the world on Treffert's list, 300 were born that way. Only 30 acquired their abilities.
It wasn't until recently that scientists began figuring out what actually causes savant syndrome. In 2003, Bruce Miller, a professor of neurology at the University of California-San Francisco, discovered that some patients with a degenerative brain disease gained incredible artistic abilities as their condition worsened. The disease is called frontotemporal dementia (FTD), and it primarily affects the front-left portions of the brain.
FTD's limited pattern of degeneration is a crucial detail; patients who suffer from Alzheimer's, for example -- a disease that affects the entire brain -- don't generally show savant-like abilities. Why might savant syndrome be linked to a very specific kind of brain damage? One theory has it that since FTD leaves the rest of the brain alone, the unaffected regions step in to compensate for the loss of tissue, leading to what Treffert calls "the three Rs": recruitment, rewiring, and release.
"What happens is that there is injury," said Treffert. "There is then recruitment of still-intact cortical tissue. There is rewiring [of brain signals] through that intact tissue, and then there is the release of dormant potential within that brain area." In other words, savants may be unlocking parts of the brain the rest of us simply don't have access to.
Or do we?
It strains belief, but completely ordinary people are in fact capable of gaining savant-like skills for short periods of time. Thanks to a piece of equipment called the Medtronic Mag Pro, one researcher has managed to temporarily replicate the kind of brain "damage" seen among FTD patients in healthy humans:
A series of electromagnetic pulses were being directed into my frontal lobes, but I felt nothing. Snyder instructed me to draw something. ''What would you like to draw?'' he said merrily. ''A cat? You like drawing cats? Cats it is.''
Two minutes after I started the first drawing, I was instructed to try again. After another two minutes, I tried a third cat, and then in due course a fourth. Then the experiment was over, and the electrodes were removed. I looked down at my work. The first felines were boxy and stiffly unconvincing. But after I had been subjected to about 10 minutes of transcranial magnetic stimulation, their tails had grown more vibrant, more nervous; their faces were personable and convincing. They were even beginning to wear clever expressions.
In fairness, a few drawings don't prove very much. But Allan Snyder -- whom, Treffert confirms, has worked with Bruce Miller, the FTD scholar, before -- is developing new, more objective ways of recording the changes the Medtronic causes in his subjects.
"He calls it the 'thinking cap,' " Treffert joked.
The prospect of willfully inducing creativity conjures images of an augmented future, one where people carry around portable brain machines and give themselves a zap when circumstances demand an extra burst of intelligence. Maybe some people will choose to be permanently buzzed, at the cost of some verbal ability.
It sounds like science fiction. But the reality may be even more outlandish. Now that scientists understand how savant syndrome occurs, new research is turning to the underlying origins of the special abilities themselves. Most of it remains a mystery -- a loose collection of questions more than anything resembling answers. For example, how is it that somebody like Derek Amato, who'd never demonstrated any musical talent before hitting his head at the bottom of a pool, could suddenly handle jazz and classical pieces of astounding complexity without training? How is it that someone can suffer a stroke and wake up later only to discover that their English is tinged with a foreign accent?
Treffert thinks this could be the result of something called genetic memory.
"Some savants are very disabled," said Treffert, "yet they know the rules of math, they know the rules of music, they know the rules of art. But they've never been taught that. Well, how can that get there? The only way it can get there is genetically."
If Treffert's hypothesis is true, it potentially upends a lot of what we know about genetics -- not disproving it, necessarily, but vastly expanding the boundaries of what we think our DNA to be capable of. Could genes be more than a way to pass on physical traits? Could they, in fact, also be used to transmit knowledge from one generation to another? If so, what kind?
Scientists aren't the only ones to be fascinated by this idea. In the blockbuster video game Assassin's Creed, players delve into the main character's genetic memory archives and re-experience events from his ancestors' lifetimes. The franchise takes gamers through vivid "memories" of medieval Jerusalem, Renaissance-era Italy, and Ottoman-ruled Constantinople. No doubt the revelations held within our own DNA are much less exotic, but that's not stopping epigeneticists from plowing ahead. A major breakthrough in genetic memory may be no more than a decade away, Treffert estimates.
As neuroscientists increasingly discover how little they really know about the brain, what we do know is beginning to resemble the half-formed inklings about the equine gait that so boggled people up until 135 years ago. Connecting the dots might take a stroke of genius. But savant-inspired research is leading the way. Eadweard Muybridge would be proud.