Sports Vision

A couple of informative sites...
http://shapirolab.net/IllusionScience/CurveBallShapiroIC2009.swf
Scientifically Speaking
http://www.hightechvisiontraining.com/scientifically.htm
Hitting, broken down physiologically, is a series of ocular and brain based actions that in turn cause a physical reaction. The goal of our conditioning process over time is to create an automatic, solidly conditioned reflex of the muscles that swing the bat which is triggered by a visual stimulus of the retina and is instantaneously interpreted by the brain as correct (a strike), to accurately contact the ball. Thought is totally bypassed. As the players’ repetitions increase, the brain is adjusting and creating stronger and quicker neurological pathway between the eyes, brain and muscles.
You must keep the ball in your central vision to accurately follow the ball into the hitting zone. When the ball travels out of your central vision plane to your peripheral vision, an optical illusion occurs making you think that the ball is curving when it is actually going straight. Here is a link to an optical illusion to illustrate the principals, courtesy of Professor Arthur Shapiro & Illusionsciences.com