How baseball batters keep their eyes on the ball

A new study suggests that head movements play a surprisingly important role in tracking pitches in baseball, even though players at bat follow coaches' advice to "keep your eye on the ball".

The findings lend new insights into how batters accomplish the complex task of tracking a pitched ball-and might even lead to new strategies designed to improve their ability to see pitches, according to the study by Nicklaus F. Fogt, OD, PhD, FAAO, and Aaron B., Zimmerman, OD, MS, FAAO, of The Ohio State University College of Optometry.

Doctors Fogt and Zimmerman designed an experimental setup to monitor eye and head tracking movements in a group of 15 Division I collegiate baseball players.

The players tracked, but did not swing at, a large number of balls pitched by a pneumatic pitching machine. Eye and head movements were synchronized with trajectory of the pitches.

"On average, eye gaze position matched the target position well throughout the trajectory," according to the researchers. But most of the time the ball was in the air, the players tracked it with their head-they moved their eyes very little until late in the pitch trajectory.

The findings are consistent with a previous study of pitch tracking in a Major League Baseball player. But they contrast with studies of fielders, who primarily track fly balls to the point where it will land, but move both their eyes and head when attempting to catch the ball.

"Hitting a baseball is a remarkably difficult task," Drs Fogt and Zimmerman write.

For a pitch traveling 90 miles per hour, the batter has only about one-fourth of a second to decide "when and at what location the ball will arrive and whether to swing the bat."

The new study was designed to assess the eye and head movement strategies used in tracking pitched balls, and whether they were consistent between players.

The study is published in Optometry and Vision Science, official journal of the American Academy of Optometry.