Translating Sleep Research: Does Sleep Promote Learning a Functional Motor Task?

Abstract

Sleep has been demonstrated to produce off-line improvements in motor learning in young adults. Evidence of sleep-dependent off-line motor learning has been demonstrated across a wide variety of simple motor tasks that have limited implications in rehabilitation. It remains unclear whether a functional motor task that is clinically-relevant will benefit from sleep to produce off-line motor skill enhancement. Addressing this question was the purpose of this dissertation. A novel walking task was used to assess the role of sleep in learning a functional motor task in young adults. Twenty-four young individuals were randomly assigned to either the sleep or the no-sleep group. Results indicate that young participants who slept after practicing the novel walking task demonstrated a significant off-line improvement in performance on the functional task, while those participants who stayed awake failed to demonstrate off-line learning. Only a few recent studies have investigated sleep-dependent off-line motor learning in older adults, and the findings of these studies offer mixed conclusions. Only one study has examined the role of sleep in motor learning in middle-aged adults. These studies all used simple motor tasks. Therefore, we examined sleep-dependent off-line learning of the novel walking task in 20 middle-aged and 20 older adults. Only the middle-aged and older adults in the sleep condition demonstrated significant off-line improvement in performance on the novel walking task. However, when compared with the magnitude of off-line learning in young adults, the results indicate that the magnitude of off-line improvement was less for middle-aged and older adults groups. In summary, this body of work indicates that sleep enhances learning a functional motor task that is clinically-relevant in young, middle-aged, and older adults. Clinicians should consider sleep as an important factor when structuring rehabilitation interventions. Emphasis should be placed on addressing sleep disorders and ensuring adequate sleep for individuals who undergo rehabilitation.