Factors such as driving speed and task complexity when using foveal vision (using the central portion of the retina) are generally regarded as related to the narrowing of the visual field. People acquire visual information using not only foveal vision but also using peripheral vision. The functional visual field is affected by the workload place on foveal vision, the level of concentration, the familiarity with and context of the peripheral stimulus, and environmental stress. This article reports on a study undertaken to examine whether increasing foveal task complexity would cause the functional field to shrink as a result of a visual funneling effect. The study included 8 male participants undergoing 3 levels of task complexity and 4 levels of visual angle. The authors found that the miss rate in the peripheral vision task tended to increase with the increase in not only the complexity of the foveal task but also the visual angle. This indicates visual funneling. However, the authors did not find a corresponding increase observed with response time (response time was not a sensitive measure of visual funneling). The authors conclude with a brief discussion of how their findings may apply to safe driving situations, including cell phone use or switch operation and peripheral vehicle detection during driving.
Abstract