Journal of Experimental Psychology: Applied. 2004, Vol. 10, No. 1, 42–54
Author: Rob Gray

Main point:

Experiments with baseball batters (10 expert players, 10 novice players). Exp 1. Three conditions: dual-task when attention was drawn to an extraneous stimuli (sound signal) while player was hitting the ball, dual-task condition when attention was drawn to the hitting process, and single-task condition, when the sound signal could be ignored. Results: in the first condition, novices showed decrease in performance, but not the experts. In the second condition, it was vice-versa. In the single-task condition the experts outperformed the novices, of course.

The author says: “Clearly, unlike more experienced players, novices do not seem to have sufficient available attentional resources to simultaneously hit and attend to extraneous sensory information.”