Robust control of skilled actions requires the flexible combination of multiple sources of information. Here we examined the role of gaze during high-speed locomotor steering and in particular the role of feedback from the visible road edges. Participants were required to maintain one of three lateral positions on the road when one or both edges…

Whereas physiological studies indicate that illusory contours (ICs) are signaled in early visual areas at short latencies, behavioral studies are divided as to whether IC processing can proceed in a fast, automatic, bottom-up manner or whether it requires extensive top-down intracortical feedback or even awareness and cognition. Here, we employ a…

Previous research has shown that actions impair the visual perception of categorically action-consistent stimuli. On the other hand, actions can also facilitate the perception of spatially action-consistent stimuli. We suggest that motorvisual impairment is due to action planning processes, while motorvisual facilitation is due to action control…

Three experiments investigated the impact of planning and preparing a manual grasping or pointing movement on feature detection in a visual search task. The authors hypothesized that action planning may prime perceptual dimensions that provide information for the open parameters of that action. Indeed, preparing for grasping facilitated detection…

D. R. Proffitt and colleagues (e. g., D. R. Proffitt, J. Stefanucci, T. Banton, & W. Epstein, 2003) have suggested that objects appear farther away if more effort is required to act upon them (e.g., by having to throw a ball). The authors attempted to replicate several findings supporting this view but found no effort-related effects in a variety…

The authors examined observers steering through a series of obstacles to determine the role of active gaze in shaping locomotor trajectories. Participants sat on a bicycle trainer integrated with a large field-of-view simulator and steered through a series of slalom gates. Steering behavior was determined by examining the passing distance through…

Walking without vision results in veering, an inability to maintain a straight path that has important consequences for blind pedestrians. In this study, the authors addressed whether the source of veering in the absence of visual and auditory feedback is better attributed to errors in perceptual encoding or undetected motor error. Three…

Using a continuous tracking task, the authors examined whether stopping is resistant to expectancies as well as whether it is a representative measure of response control. Participants controlled the speed of a moving marker by continuously adjusting their response force. Participants stopped their ongoing tracking in response to auditory signals…

Why are human observers particularly sensitive to human movement? Seven experiments examined the roles of visual experience and motor processes in human movement perception by comparing visual sensitivities to point-light displays of familiar, unusual, and impossible gaits across gait-speed and identity discrimination tasks. In both tasks, visual…

The authors tested whether the effects of the Ebbinghaus illusion on grasping are corrected during late phases of the movement. Surprisingly, the grasp aperture was corrected neither under no-vision (N = 52) nor under full-vision (N = 48) conditions. The authors show that previous reports of a correction (e.g., S. Glover & P. Dixon, 2002a) are due…

During locomotion, retinal flow, gaze angle, and vestibular information can contribute to one's perception of self-motion. Their respective roles were investigated during active steering: Retinal flow and gaze angle were biased by altering the visual information during computer-simulated locomotion, and vestibular information was controlled…

Six results are reported. (a) Reaching accuracy increases when visual capture of the target is allowed (e.g., target on vs. target off at saccade onset). (b) Whatever the visual condition, trajectories diverge only after peak acceleration, suggesting that accuracy is improved through feedback mechanisms. (c) Feedback corrections are smoothly…

This study explored visual control strategies for braking to avoid collision by manipulating information about speed of self-motion. Participants watched computer-generated displays and used a brake to stop at an object in the path of motion. Global optic flow rate and edge rate were manipulated by adjusting eyeheight and ground-texture size.…