Environmental enrichment (EE) has been widely used as a means to enhance brain plasticity mechanisms (e.g., increased dendritic branching, synaptogenesis, etc.) and improve behavioral function in both normal and brain-damaged animals. In spite of the demonstrated efficacy of EE for enhancing brain plasticity, it has largely remained a laboratory phenomenon with little translation to the clinical setting. Impediments to the implementation of enrichment as an intervention for human stroke rehabilitation and a lack of clinical translation can be attributed to a number of factors not limited to: (i) concerns that EE is actually the “normal state” for animals, whereas standard housing is a form of impoverishment; (ii) difficulty in standardizing EE conditions across clinical sites; (iii) the exact mechanisms underlying the beneficial actions of enrichment are largely correlative in nature; (iv) a lack of knowledge concerning what aspects of enrichment (e.g., exercise, socialization, cognitive stimulation) represent the critical or active ingredients for enhancing brain plasticity; and (v) the required “dose” of enrichment is unknown, since most laboratory studies employ continuous periods of enrichment, a condition that most clinicians view as impractical. In this review article, we summarize preclinical stroke recovery studies that have successfully utilized EE to promote functional recovery and highlight the potential underlying mechanisms. Subsequently, we discuss how EE is being applied in a clinical setting and address differences in preclinical and clinical EE work to date. It is argued that the best way forward is through the careful alignment of preclinical and clinical rehabilitation research. A combination of both approaches will allow research to fully address gaps in knowledge and facilitate the implementation of EE to the clinical setting.

Embedding an enriched environment in an acute stroke unit increased activity in stroke patients.

Objectives: To explore the effect of environmental enrichment within an acute stroke unit on how and when patients undertake activities, and the amount of staff assistance provided, compared with a control environment (no enrichment). Design: This is a substudy of a controlled before–after observational study. Setting: The study was conducted in an Australian acute stroke unit. Participants: The study included stroke patients admitted to (1) control and (2) environmental enrichment period. Intervention: The control group received standard therapy and nursing care, which was delivered one-on-one in the participants’ bedroom or a communal gym. The enriched group received stimulating resources and communal areas for mealtimes, socializing and group activities. Furthermore, participants and families were encouraged to increase patient activity outside therapy hours. Main measures: Behavioral mapping was performed every 10 minutes between 7.30 a.m. and 7.30 p.m. on weekdays and weekends to estimate activity levels. We compared activity levels during specified time periods, nature of activities observed and amount of staff assistance provided during patient activities across both groups. Results: Higher activity levels in the enriched group (n = 30, mean age 76.7 ± 12.1) occurred during periods of scheduled communal activity (P < 0.001), weekday non-scheduled activity (P = 0.007) and weekends (P = 0.018) when compared to the control group (n = 30, mean age 76.0 ± 12.8), but no differences were observed on weekdays after 5 p.m. (P = 0.324). The enriched group spent more time on upper limb (P < 0.001), communal socializing (P < 0.001), listening (P = 0.007) and iPad activities (P = 0.002). No difference in total staff assistance during activities was observed (P = 0.055). Conclusion: Communal activities and environmental resources were important contributors to greater activity within the enriched acute stroke unit.