The A - Z of Sports Vision - Eye Dominance

If you point to a distant object, close one eye and then the other, you’ll notice that when one eye is closed you’re no longer lined up. This is the effect of parallax, when there are two lines of sight, one for each eye. The brain has to choose one eye for alignment, and this is known as the dominant eye, though “aligning eye” might be a better description. You might think that eye dominance would match handedness, but there are many instances of “cross dominance”, For instance, Griffiths (2002) found that 40% of left-handed batsmen playing for Scotland were right-eye dominant. Even in archery, where aiming is obviously the essence of the sport, 18.75% of internationals studied were found to have cross dominance. In his study, Griffiths found that deliberately making the dominant eye blurred strongly affected the performance of clay pigeon shooters, not surprisingly. But for tennis players, the greater effect came from blurring the non-dominant eye. And these weren't just any tennis players: they included previous winners and finalists at Wimbledon, The US, Australian and French Open Championships. And it was those who were right-handed and right-eye dominant who were most affected when their non-dominant (left eye) was blurred. This suggests that it would be their depth perception that was affected. In cricket, eye dominance can affect the stance, with a right-eye dominant right-handed batsman requiring a slightly more open stance to ensure that the right eye is aligned with the ball. Unfortunately, this stance is often coached to youngsters without checking their eye dominance first. Eye dominance may also be part of the explanation for the number of elite cricketers whose batting stance is the opposite of their bowling action. Misalignment of the dominant eye is a well documented cause of errors when putting in golf. I've seen several cases where a consistent missing of putts to one side has been caused by using different eyes when aligning the ball with the hole and the putter to the ball. I use a different eye for alignment depending on which hand I use for putting, which is why both hands should be used when testing for eye dominance. Bizarrely, I naturally align with my left eye when I point with my right hand, and vice versa. I've no idea why I do this, but it does explain why, when I used to shoot, my first shot was always off target, and I had to aim to the side to compensate. If I’d known, I could have just closed my left eye. David Donner