Abstract
It is common for fans at basketball games to try to hinder opposing free throw shooters by moving or behaving provocatively within their view. Distraction ideas that have been informally tested at college and professional games include presenting uniform motion by having fans move in concert, and showing provocative pictures near the endline. Yet, substantial research in perception-action supports that actions like ball throwing may be resistant to potential distortions and distractions. In the current study, we examine if images projected directly onto a white basketball backboard can affect shooting accuracy. Presumably this type of background stimulus represents a theoretical extreme that occurs immediately adjacent to the shooter's intended target, and may be approximated in real games which use clear Lucite backboards. The images that we projected onto the backboard included either continuous motion gradients to produce systematic movement, or provocative pictures to distract attention. The moving stimuli varied in speed (fast or slow), texture (dot or line), and direction (laterally or in depth). The emotionally distracting images varied in pleasantness. Ten participants each shot 44 free throws under the various background conditions, and ball position was measured using an eight-camera VICON motion-capture system. Our findings show that while there may be some systematic effects of background stimuli, there was not a significant general decrement in shooting accuracy. In particular, shooting accuracy with displayed motion in depth did not significantly differ from that with either lateral motion or blank control conditions, and with pleasant pictures it did not differ from with unpleasant ones. The findings suggest that background antics are not likely to have a notable impact on the free throw shooting accuracy of skilled players. More generally the findings provide further support for the robustness and independence of the perception-action system to resist distortion and distraction.