Point of aim and eye movement behavior in a rolling task

Abstract

Skilled bowlers (N = 7) participated in an experiment examining visual fixations and accuracy in a rolling task. Bowlers performed trials looking at each of 4 visual targets: 20, 40, and 60 feet down the 60-foot bowling lane, and at a location of their choosing. Error in ball position relative to the visual target increased with visual target distance. Variable error at the visual target was significantly lower in the self-selected condition as compared to the 40- and 60-feet conditions. Variable and absolute error relative to the pins (60 feet down the lane) was lowest in the self-selected aiming point and second lowest when aiming 60 feet down the lane. Absolute error at the pins was significantly lower in the free condition as compared to the 40- and 60-feet conditions. Final fixation duration, defined as the last visual fixation (at least 100 ms in which the angle of the eye remains within a 1ocone) prior to movement initiation, was significantly longer than the average duration of all fixations during the movement. The average fixation was significantly longer than the last fixation before release. The final fixation duration and the duration of the last fixation before ball release did not vary with ball accuracy at the visual target or with accuracy at the pins. Final fixation duration tended to increase with visual target distance suggesting that final fixation duration increases with task difficulty.