Walking Produces Oscillations in Orientation and Direction Perception at the Step Rate

Abstract

Walking is one of the most stereotyped oscillatory movement able-bodied individuals produce. It is highly consistent within and across individuals, with people taking ~5000 steps a day on average at approximately 2 Hz. This consistency and its ubiquitous role in daily living make walking an ideal behaviour for investigating perception under active conditions. Across two virtual reality experiments, we tested whether stride-based oscillations, as seen in visual detection performance, also occur for visual orientation and motion direction discrimination. Participants followed a simulated screen along a linear path in virtual space while visual stimuli were presented on the screen. Group-level performance in both visual tasks oscillated at approximately two cycles per stride. Peak performance in visual orientation identification aligned with the late swing phase of each step, whereas peak performance in motion direction identification aligned with the late stance or early swing phase. These findings extend recent work showing that visual perception is modulated at the step rate during locomotion.