Abstract
In this study, we measured the objective and subjective sizes of effective visual fields in game play situations by using a gaze-contingent window method. The peripheral visual field was restricted to an area around the gaze by window masks of various sizes while participants played one of three video games (i.e., car racing, falling block puzzle, and word puzzle). The quantitative relationship between window size and game performance confirmed that the type of video game significantly affected the objective size of the effective visual field. The subjective size of effective visual fields was measured by asking the participants to adjust the window size to the extent they felt their performance would change. The subjective measures of effective visual field were similar to the objective measures for the car racing game and the falling block puzzle game. However, we found that the objective and subjective sizes of effective visual field were not comparable in the word puzzle game. These results suggest that players do not always recognize the size of an effective visual field accurately while playing video games. The present study indicates that the gaze-contingent window method is useful for revealing the spatial characteristics of effective visual fields, and that the method developed for measuring the subjective effective visual field is also applicable for dynamic visual-motor tasks.