For baseball players, the advice is as old as the game itself: Keep your eyes on the ball. Now, new research suggests the split-second reaction needed to hit a baseball involves head movement — not just eye tracking.

Ohio State University researchers wanted to answer two big questions: Do batters truly keep their eyes on incoming pitches? If so, does that confer some sort of batting advantage? It turns out that the answer is complicated. Yes, batters keep their eyes on the ball — but they do so by moving their heads and not just their eyes.

For batters, much happens in the half-second that a baseball travels from the pitcher’s hand to the catcher’s glove. It’s a lot to take in — a torrent of neural and visual signals that can sometimes be conflicting.

The researchers noted that tracking a baseball with head movements also means overriding a specific reflex that normally allows vision to remain stable while the head moves.

Their findings consistently showed that players at all levels kept their eyes on the ball by moving their heads. They also determined the process of swinging a bat is somewhat independent of what the head and eyes are doing in the moment.

So why would a minute movement deserve so much attention? The researchers have a simple answer: If a coach is teaching a batter what to do, then they need to know which nuances of a batting strategy are helpful.

Getting those answers about visual processing also has implications for everyday activities such as driving or pouring a glass of milk.

To be sure, hand, eye and head coordination are important to more than just baseball. Otherwise, you might be crying over spilled milk.