Related Experiment Video
Updated: May 19, 2026
08:12
Experimental Methods to Study Human Postural Control
Published on: September 11, 2019
Postural and locomotor contributions to affordance perception
Yawen Yu1, Thomas A Stoffregen
1School of Kinesiology, University of Minnesota, MN, USA. yawenyu@unomaha.edu
Journal of Motor Behavior
|September 1, 2012
Summary
Locomotor control, not head restraint, significantly improved wheelchair users' perception of affordances. Practicing self-powered wheelchair movement enhanced judgments of navigable spaces.
Area of Science:
- Rehabilitation Science
- Human Movement Science
- Perception and Cognition
Background:
- Perception of environmental affordances is crucial for independent mobility.
- Wheelchair users' ability to accurately judge navigable spaces (affordances) is vital for safety and autonomy.
- Understanding factors influencing affordance perception, such as locomotor control, is key to improving mobility interventions.
Purpose of the Study:
- To determine the relative importance of locomotor control versus postural control in the perception of environmental affordances for wheelchair users.
- To investigate whether brief practice with wheelchair locomotion influences the accuracy of judging minimum lintel heights.
- To examine the effect of head restraint during practice on subsequent affordance judgments.
Main Methods:
- Participants judged the minimum lintel height passable in a wheelchair.
- A brief (∼2 min) practice session involved wheelchair locomotion, either self-powered or experimenter-pushed, with or without head restraint.
- Affordance judgment accuracy was compared between groups based on locomotion control and head restraint conditions.
Main Results:
- Head restraint during practice did not affect the accuracy of affordance judgments.
- Participants who controlled their own wheelchair locomotion during practice demonstrated significantly more accurate affordance judgments compared to those who did not.
- Self-controlled locomotion practice enhanced the perception of navigable space affordances.
Conclusions:
- Locomotor control, specifically self-powered movement, plays a critical role in accurately perceiving environmental affordances for wheelchair users.
- Postural control, as manipulated by head restraint, was not found to be a significant factor in this context.
- These findings suggest that interventions promoting active participation and control in mobility tasks may improve spatial perception and functional independence for wheelchair users.
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