Evaluating variable resolution displays with visual search: Task performance and eye movements

Gaze-contingent variable resolution display techniques allocate computational resources for image generation preferentially to the area around the center of gaze where visual sensitivity to detail is the greatest. Although these techniques are computationally efficient, their behavioral consequences with realistic tasks and materials are not well understood. The behavior of human observers performing visual search of natural scenes using gaze-contingent variable resolution displays is examined. A two-region display was used where a high-resolution region was centered on the instantaneous center of gaze, and the surrounding region was presented in a lower resolution. The radius of the central high-resolution region was varied from 1 to 15 degrees while the total amount of computational resources required to generate the visual display was kept constant. Measures of reaction time, accuracy, and fixation duration suggest that task performance is comparable to that seen for uniform resolution displays when the central region size is approximately 5 degrees.