LAUSR

R esearch conducted over the last 30 years has demonstrated that a variety of factors can influence motor learning and the strength of motor memories. For example, the amount and structure of practice (ie, constant or variable) as well as feedback schedule have been shown to influence motor skill learning in healthy populations.1 In an effort to maximize patient outcomes, well-established principles of motor learning are commonly incorporated into therapeutic interventions in neurologic clinical practice. Yet, minimal work has been done to determine (1) how well various principles of motor learning translate into neurologic populations, and (2) whether they apply broadly across different learning mechanisms. In this issue of the Journal of Neurologic Physical Therapy (JNPT), Helm and colleagues2 begin to address this knowledge gap by investigating how practice structure (in this case, variable vs constant practice) affects retention of a novel gait pattern learned through split-belt treadmill adaptation in persons after stroke. Individuals with chronic stroke learned to walk on a split-belt treadmill in either constant (2:1 speed ratio for 15 minutes) or variable (switching between 2:1, 1.5:1, and 2.5:1 speed ratios for 15 minutes in total) belt speed conditions. On a second day, participants again walked on the split-belt