Abstract
Do we choose to direct our gaze at uniform visual patterns when engaged in a cognitively demanding task? We addressed this question by investigating the relationship between working memory (WM) load, visual complexity, and gaze position. We hypothesized that when WM load is high, people may seek out regions of low visual complexity with their gaze. Subjects viewed Mondrian-type images consisting of variable-sized colored squares appearing on a mosaic background. Visual complexity was manipulated within each display by varying the size of the squares relative to the mosaic, under the assumption that higher edge content and diversity of color leads to greater visual complexity. We manipulated WM load using a serial recall task consisting of variable-length (3, 5, 7 or 9) digit strings. On each trial, subjects were presented with an image and an auditory sequence of digits. Following a 5-second retention interval, subjects were asked to report back the digits. The image remained visible to subjects throughout the trial, and their only gaze-related instruction was to refrain from closing their eyes. Analyses revealed no effect of WM load or visual complexity on eye gaze during either the encoding phase or the retention interval. However, during recall subjects looked more frequently to regions of low visual complexity, and this increased linearly with WM load. These findings suggest that the high cognitive demands during recall cause subjects to seek out areas of low visual complexity with their gaze, perhaps to minimize interference produced by automatic visual processes.