The brain begins by setting a goal—pick up the fork, say, or deliver the tennis serve—and calculates the best course of action to reach it. As the brain starts issuing commands, it also begins to make predictions about what sort of sensations should come back from the body if it achieves the goal. If those predictions don’t match the actual sensations, the brain then revises its plan to reduce error. Shadmehr and Krakauer’s work demonstrates that the brain does not merely issue rigid commands; it also continually updates its solution to the problem of how to move the body. Athletes may perform better than the rest of us because their brains can find better solutions than ours do.To understand how athletes arrive at these better solutions, other neuroscientists have run experiments in which athletes and nonathletes perform the same task. This past January Claudio Del Percio of Sapienza University in Rome and his colleagues reported the results of a study in which they measured the brain waves of karate champions and ordinary people, at rest with their eyes closed, and compared them. The athletes, it turned out, emitted stronger alpha waves, which indicate a restful state. This finding suggests that an athlete’s brain is like a race car idling in neutral, ready to spring into action.
Del Percio’s team has also measured brain waves of athletes and nonathletes in action. In one experiment the researchers observed pistol shooters as they fired 120 times. In another experiment Del Percio had fencers balance on one foot. In both cases the scientists arrived at the same surprising results: The athletes’ brains were quieter, which means they devoted less brain activity to these motor tasks than nonathletes did. The reason, Del Percio argues, is that the brains of athletes are more efficient, so they produce the desired result with the help of fewer neurons. Del Percio’s research suggests that the more efficient a brain, the better job it does in sports. The scientists also found that when the pistol shooters hit their target, their brains tended to be quieter than when they missed.
Good genes may account for some of the differences in ability, but even the most genetically well-endowed prodigy clearly needs practice—lots of it—to develop the brain of an athlete. As soon as someone starts to practice a new sport, his brain begins to change, and the changes continue for years. Scientists at the University of Regensburg in Germany documented the process by scanning people as they learned how to juggle. After a week, the jugglers were already developing extra gray matter in some brain areas. Their brains continued to change for months, the scientists found.