A typical major league fastball travels about 10 feet in just the 75 milliseconds that it takes for sensory cells in the retina to confirm that a baseball is in view and for information about the flight path and velocity of the ball to be relayed to the brain. The entire flight of the baseball from the pitcher's hand to the plate takes just 400 milliseconds. And because it takes half that time merely to initiate muscular action, a major league batter has to know where he is swinging shortly after the ball leaves the pitcher's hand—well before it's even halfway to the plate.
The window for actually making contact with the ball, when it is in reach of the bat, is five milliseconds, and because the angle of the ball relative to the hitter's eye changes so rapidly as the ball gets closer to the plate, the advice to "keep your eye on the ball" is impossible to follow. Humans don't have a visual system fast enough to track the ball all the way in. A batter could just as well close his eyes once the ball is halfway to home plate. Given the speed of the pitch and the limitations of our physiology, it seems to be a miracle that anybody hits the ball at all.
Still, Pujols and other All-Stars see—and crush—95-mph fastballs for a living. So why are they transmogrified into Little Leaguers when faced with 68-mph softballs? It's because the only way to hit a ball traveling at high speed is to be able to see into the future, and when a baseball player faces a softball pitcher, he is stripped of his crystal ball.
Janet Starkes was a 5'2" point guard who spent one summer on the Canadian women's national basketball team nearly 40 years ago. Her lasting influence on sports, though, would come off the court, from the work she started as a graduate student at the University of Waterloo in Ontario. Her research was to try to figure out why good athletes are, well, good.
Tests of innate physical hardware—qualities with which an athlete is apparently born, such as simple reaction time—had done astonishingly little to explain expert performance in sports. The reaction times of elite athletes always hovered around one fifth of a second, the same as the reaction times of random people.
So Starkes looked elsewhere. She had heard of research on air-traffic controllers that used "signal-detection tests" to gauge how quickly an expert controller can sift through visual information to determine the presence or absence of critical signals. And she decided that conducting studies like these, of perceptual cognitive skills that are learned through practice, might prove fruitful. So in 1975, as part of her graduate work at Waterloo, Starkes invented the modern sports "occlusion" test.
She gathered thousands of photographs of women's volleyball games and made slides of pictures in which the volleyball was in the frame and others in which the ball had just left the frame. In many photos, the orientation and movement of players' bodies were nearly identical regardless of whether the ball was in the frame, since little had changed in the instant after the ball exited the picture.
Starkes then connected a scope to a slide projector and asked elite and novice volleyball players to look at the slides for a fraction of a second apiece and decide whether the ball was or was not in the frame. The glance was too quick for the viewers actually to see the ball, so the idea was to determine whether some of the athletes were seeing the entire court and the body language of players in a way that allowed them to figure out whether the ball was present.
The results of the first occlusion tests astounded Starkes. Unlike in reaction-time tests, the difference between top volleyball players and novices was enormous. For the elite players, a fraction-of-a-second glance was all they needed to determine whether the ball was present. And the better the player, the more quickly she could extract pertinent information from each slide.
In one instance Starkes tested members of the Canadian national women's volleyball team, which at the time included one of the best setters in the world. The setter was able to deduce whether the volleyball was present in a picture that was flashed before her eyes for 16 thousandths of a second. "That's a very difficult task," says Starkes, who would become one of the world's most influential expert-performance researchers. "For people who don't know volleyball, in 16 milliseconds all they see is a flash of light."