FIGURE 1.

Experimental tasks and conditions. The experimental conditions consisted of external cueing, internal cueing, and action observation during stance and gait. Stance conditions always preceded the gait conditions, but the order of the conditions was counterbalanced within stance/gait blocks and across participants. Each condition lasted 4 minutes, with the exception of uncued stance (commonly referred to as quiet stance). Prior to the main experiment, participants practiced walking on the treadmill at a comfortable speed to determine their preferred cadence. The corresponding belt speed remained constant throughout the experiment. Resting breaks were encouraged between all conditions.