Good information above. Bottom line... Use common sense and if you have a medical condition that affects how you might be driving, let your instructor know (maybe others too, but at least the person who puts their safety in your hands)
I had the pleasure of instructing a student who, for most of the day, kept driving about 6 feet off the apex in right corners, but much closer on left corners. I couldn't figure out why, as I assumed my instruction was spot on
. It was only during the track side dinner, that the student relayed a story about how he no longer sails because of an accident that has limited his vision in his right eye! Great! I spend all day at high speeds with a person who didn't feel the need to tell me that he is almost legally blind in one eye! While the next day we were able to improve, I felt much better knowing my students limitations.. and knowing them up front would have been better still.