Visual perception in familiar, complex tasks

Visual perception is virtually effortless, operating at a level below conscious experience. Because it most frequently operates without attentive intervention, it does not yield to introspective report. The foveal/peripheral distribution of photoreceptor density in the human eye requires a mechanism to rapidly re-target areas in the environment for visual inspection. The eyes are moved both toward areas where high-acuity, central vision is required and toward objects of interest to the current task. Monitoring those eye movements can provide a window into perception. Subjects' eye movements were monitored while they performed the familiar, complex task of hand-washing. Analysis revealed a novel perceptual strategy, in which objects of future interaction were foveated seconds before the information was "needed" for a task. These lookahead fixations are task-dependent; while they occurred in over 3% of fixations in the hand-washing task, their frequency fell to less than 1% in a control experiment. We propose that the look-ahead fixations represent a strategic deployment of attentional and visual resources to optimize information gathering during natural tasks.