Working memory and mental practice outcomes after stroke

Objective: To examine the relationship between working memory and motor improvement obtained after a single training session combining mental and physical practice. Design: Before-after trial. Setting: Laboratory of a university-affiliated research rehabilitation center. Participants: A sample of 12 patients with stroke and 14 age- and Render-matched healthy subjects. Intervention: In a single session, patients were trained with combined mental and physical practice to increase the loading on the affected leg while standing up and sitting down. Main Outcome Measures: Motor improvement as measured by the percentage change in limb loading on the affected limb after training, and 24 hours later (follow-up), and the relationship between working memory and percentage motor improvement. Results: The loading on the affected leg was improved after training (P<.01) and at follow-up (P<.05), and working memory scores at follow-up correlated significantly (P<.004 to P<.007) with the level of improvement. The visuospatial domain yielded the strongest correlation (r=.83), followed by the verbal (r=.62) and kinesthetic (r=.59) domains. Conclusions: These results suggest that the outcome (improved limb loading) of mental rehearsal with motor imagery depends on the ability to maintain and manipulate information T in working memory. (C) 2004 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation.