CSM ABSTRACTS: Platforms, Thematic Posters, & Posters for CSM 2006: THEMATIC POSTER SESSION: Motor Learning Saturday 1: 30–3: 30
Purpose/Hypothesis: In general, random order practice has been shown to be superior for motor learning in young adults compared to blocked order task practice. Random practice is thought to be beneficial to learning since the learner's task-switching capability is strengthened. Since individuals with Parkinson disease (PD) have a task-switching deficit, the purpose of this study is to investigate the effects of practice order on learning goal-directed arm movements in individuals with PD compared to age-matched controls (CN). We hypothesize that blocked order practice is superior for motor learning for those with mild PD.
Number of Subjects: Ten adults with mild PD (mean age= 68.7 yrs; Hoehn & Yahr I or II; randomly assigned to either blocked practice, PDB, n=5, or random practice, PDR, n=5) and 8 age-matched controls (mean age= 57.1, assigned to blocked practice, CNB, n=4, or random practice, CNR, n=4) participated.
Materials/Methods: All participants practiced 3 lever arm movement patterns, each with specific spatial and temporal requirements. Performance accuracy was quantified across acquisition and delayed (day 2) retention test using root mean square error (RMSE) and timing error (TF).
Results: Both groups (PD and CN) decreased error (RMSE) across practice (p < .01).At the end of acquisition, the control groups showed more accurate performance than the PD groups. In delayed retention, the control subjects who practiced in the random condition had lower RMSE than those that practiced in the block condition (effect size, ES=0.7). Interestingly, this was not the case for the PD groups. Consistent with our hypothesis, the PD subjects who practiced with a blocked schedule were more accurate in delayed retention than the PD subjects who practiced in the random condition (ES= 0.8 for group RMSE difference). In addition, the temporal accuracy was better for the PD group that practiced in the block condition (ES= 0.8 for group TE difference).
Conclusions: Consistent with our hypothesis, adults with PD learned motor skills better in blocked order practice than in random order practice.
Clinical Relevance: This pilot data suggests that conditions of practice that may be beneficial for motor learning in healthy adults may not be as effective for individuals with PD in which task-switching deficits are commonly present.