The last decade has witnessed an increase in the number of moderate to large-scale nonpharmacologic stroke recovery trials. While a majority, having tested the superiority of a particular evidence-based intervention, returned negative findings, the rehabilitation research community has gained an important perspective for future efforts. We offer our interpretation first, on why most of the past decade’s trials failed in the sense of not supporting the primary superiority hypothesis, and, second, we provide our perspective on how to solve this problem and thereby inform the next generation of neurorehabilitation clinical trials. The first large-scale randomized controlled trial (RCT) ever conducted in neurorehabilitation was the Extremity Constraint Induced Movement Therapy Evaluation (EXCITE) trial. The majority of stroke recovery trials that followed were based on a prevailing, but as yet immature science of brain-behavior mechanisms for recovery and limited practical know-how about how to select the most meaningful outcomes. The research community had been seduced by a set of preclinical studies, ignited by the 1990’s revolution in neuroscience and an oversimplified premise that high doses of task-oriented training was the most important ingredient to foster recovery. Here, we highlight recent qualitative and quantitative evidence, both mechanistic and theory-driven, that integrates crucial social and personal factors to inform a more mature science better suited for the next generation of recovery-supportive rehabilitation clinical trials.
Patricia S. Pohl and Carolee J. Winstein
The purpose of ihis study was to compare the effects of a single practice session on performance strategies used by young and older adults to decrease movement time (MT) while maintaining accuracy of an aiming task. Five young and 5 older adult males practiced until each accumulated 500 target hits in each of two complexity conditions as defined by Fitts’s law. Participants decreased MT with practice; however, older adults had longer MTs than the young, particularly in the high-complexity condition. With practice in the low-complexity condition, participants decreased absolute acceleration and deceleration times but maintained the relative amount of MT devoted to temporal phases. In contrast, with practice in the high-complexity condition, participants decreased absolute deceleration and dwell time and changed the temporal structure. Results suggest that older adults can decrease MT with practice and that the performance strategies adopted to speed performance are more a function of task complexity than age.
Rachel Proffitt, Belinda Lange, Christina Chen, and Carolee Winstein
The purpose of this study was to explore the subjective experience of older adults interacting with both virtual and real environments. Thirty healthy older adults engaged with real and virtual tasks of similar motor demands: reaching to a target in standing and stepping stance. Immersive tendencies and absorption scales were administered before the session. Game engagement and experience questionnaires were completed after each task, followed by a semistructured interview at the end of the testing session. Data were analyzed respectively using paired t tests and grounded theory methodology. Participants preferred the virtual task over the real task. They also reported an increase in presence and absorption with the virtual task, describing an external focus of attention. Findings will be used to inform future development of appropriate game-based balance training applications that could be embedded in the home or community settings as part of evidence-based fall prevention programs.
Yi-An Chen, Yu-Chen Chung, Rachel Proffitt, Eric Wade, and Carolee Winstein
Attention during exercise is known to affect performance; however, the attentional demand inherent to virtual reality (VR)-based exercise is not well understood. We used a dual-task paradigm to compare the attentional demands of VR-based and non-VR-based (conventional, real-world) exercise: 22 older adults (with no diagnosed disabilities) performed a primary reaching task to virtual and real targets in a counterbalanced block order while verbally responding to an unanticipated auditory tone in one third of the trials. The attentional demand of the primary reaching task was inferred from the voice response time (VRT) to the auditory tone. Participants’ engagement level and task experience were also obtained using questionnaires. The virtual target condition was more attention demanding (significantly longer VRT) than the real target condition. Secondary analyses revealed a significant interaction between engagement level and target condition on attentional demand. For participants who were highly engaged, attentional demand was high and independent of target condition. However, for those who were less engaged, attentional demand was low and depended on target condition (i.e., virtual > real). These findings add important knowledge to the growing body of research pertaining to the development and application of technology-enhanced exercise for older adults and for rehabilitation purposes.