Postural and Locomotor Contributions to Affordance Perception

ABSTRACT

The authors sought to evaluate the relative importance of locomotor control and postural control in the perception of affordances. While seated in a stationary wheelchair, participants made a series of judgments about the minimum lintel height under which they could roll in the wheelchair. Prior to making judgments, participants were given brief (∼2 min) experience with wheelchair locomotion. They expected that this practice would influence the accuracy of subsequent affordance judgments. During practice, participants moved under their own power (using their hands on the wheels) or with an experimenter pushing the wheelchair. Also during wheelchair locomotion the participant's head was restrained, or was not. Results revealed that head restraint during the practice session had no effect on the accuracy of subsequent judgments. By contrast, the judgments of participants who controlled locomotion during practice were significantly more accurate than the judgments of participants who had not controlled their locomotion during practice.

Keywords:

• affordance
• exploration
• locomotion
• perception
• wheelchair

ACKNOWLEDGMENTS

The experiments were conducted as part of the doctoral dissertation of Yawen Yu at the University of Minnesota. Portions of the data were reported at the Annual Conference of the North American Society for Psychology of Sport and Physical Activity, Tucson, Arizona, June 2010.