An enriched environment improves sensorimotor function post-ischemic stroke.
OBJECTIVE
An enriched environment (EE) refers to conditions that facilitate or enhance sensory, cognitive, motor, and social stimulation relative to standard (laboratory) conditions. Despite numerous published studies investigating this concept in animal stroke models, there is still debate around its efficacy. The authors performed a systematic review and meta-analysis to determine the efficacy of an EE on neurobehavioral scores, learning, infarct size, and mortality in animal models of ischemic stroke.


METHODS
Systematic review of controlled studies of the use of an EE in experimental stroke was conducted. Data extracted were analyzed using weighted mean difference meta-analysis. For pooled tests of neurobehavioral scores, a random effects standardized method was used.


RESULTS
Animals recovering in an EE poststroke had mean neurobehavioral scores 0.9 standard deviations (95% confidence interval [CI] = 0.5-1.3; P < .001) above the mean scores of animals recovering in standard conditions and showed a trend toward improvement in learning (25.1% improvement; 95% CI = 3.7-46.6; P = .02). There was no significant increase in death. Animals exposed to an EE had 8.0% larger infarcts than control animals (95% CI = 1.8-14.1; P = .015).


CONCLUSIONS
The results indicate significant improvements in sensorimotor function with EE poststroke but suggest a small increase in infarct volume. Clarification of the underlying mechanisms requires further study but should not overshadow the observed functional improvements and their application to clinical trials during stroke rehabilitation.
Janssen
Heidi
H
Hunter Stroke Service, Hunter New England Health, New South Wales, Australia. Heidi.Janssen@hnehealth.nsw.gov.au
Bernhardt
Julie
J
Collier
Janice M
JM
Sena
Emily S
ES
McElduff
Patrick
P
Attia
John
J
Pollack
Michael
M
Howells
David W
DW
Nilsson
Michael
M
Calford
Mike B
MB
Spratt
Neil J
NJ
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D016001:Confidence Intervals; D004195:Disease Models, Animal; D004777:Environment; D020925:Hypoxia-Ischemia, Brain / Q000503:physiopathology* / Q000534:rehabilitation*; D011897:Random Allocation; D020127:Recovery of Function / Q000502:physiology*; D020521:Stroke / Q000503:physiopathology*; D000071939:Stroke Rehabilitation