[senior]

Drifter:
It's not really mental - I believe it is mostly physical! I experienced the same feelings until I realized it had more to do with how I was setting up than any mental condition. I strive to have an adequately large zone, and found on some of my "higher" level games pitchers felt I was squeezing them. Upon further review, I discovered that I was setting up in the same location for all my games.
I try to concentrate on setting my "eye-level" at the top of my zone, and have basically eliminated my concerns about the top of my zone. If you're too low, you find it difficult to pull the trigger on a pitch you're looking up at.