Visual estimation of apertures for wheelchair locomotion in novices: Perceptual judgment and motor practice.

Abstract

The aim of the present study was to determine the effects of motor practice on visual judgments of apertures for wheelchair locomotion and the visual control of wheelchair locomotion in wheelchair users who had no prior experience. Sixteen young adults, divided into motor practice and control groups, visually judged varying apertures as passable or impassable under walking, pre-practice, and post-practice conditions. The motor practice group underwent additional motor practice in 10 blocks of five trials each, moving the wheelchair through different apertures. The relative perceptual boundary was determined based on judgment data and kinematic variables that were calculated from videos of the motor practice trials. The participants overestimated the space needed under the walking condition and underestimated it under the wheelchair conditions, independent of group. The accuracy of judgments improved from the pre-practice to post-practice condition in both groups. During motor practice, the participants adaptively modulated wheelchair locomotion, adjusting it to the apertures available. The present findings from a priori visual judgments of space and the continuous judgments that are necessary for wheelchair approach and passage through apertures appear to support the dissociation between processes of perception and action.

Age and Auditory Spatial Perception in Humans: Review of Behavioral Findings and Suggestions for Future Research

“…The results revealed that participants required a larger gap when they actually walked through the gap than when they made verbal judgments from a stationary point of observation. Significant differences between perceptual judgments and actual performance have been documented in terms of whether a stair is low enough to be stepped upon ( Warren, 1984 ), an object is close enough to be grasped (e.g., Carello et al, 1989 ; Wagman and Morgan, 2010 ), an expanse can be stepped or leaped over ( Cole et al, 2013 ; Day et al, 2015 ), the slope of a surface is small enough for it to be ascended ( Kinsella-Shaw et al, 1992 ), and wheelchair users can pass through a gap (e.g., Higuchi et al, 2004 ; Stoffregen et al, 2009a ; Rodrigues et al, 2014 ).…”