Gaze patterns in the visual control of straight-road driving and braking as a function of speed and expertise

Despite decades of research, the role of gaze in car driving is still poorly understood, but racing simulators provide a suitable experimental platform to examine drivers' gaze patterns across driving tasks of increasing complexity, including driving at high speeds. In this article, we report the findings of our baseline study: gaze as a function of speed and expertise in straight-road driving and braking. In straight-road driving, gaze was increasingly constrained by increasing speed, but higher levels of expertise relaxed this constraint. However, drivers always preferred to look in the direction of their intended movement. In braking, gaze was always highly constrained, regardless of expertise and decreasing speed, and tended to be directed not only toward the drivers' intended path but also anchored on where they intended to stop. In these two tasks, gaze appears to have two primary functions: to look toward surfaces the drivers intend to approach and to look toward those they intend to avoid crossing. These functions seem to be related to the detection of the center and rate of optic expansion of the optic flow field.