Differential efficacy of modified enriched environment on motor, emotion, and cognition in cortical ischemic mice

A modified enriched environment (mEE) with 12 h per night was recently proposed and exhibited cognitive improvement. The present study aimed to evaluate the effects of different courses of mEE on different deficits in ischemic mice. Mice were subjected to photothrombotic stroke at the left sensorimotor cortex and then randomly assigned to standard environment or mEE for 7 d (St-PE) or 28 d (Ct-PE) on the third day post-stroke. Neurological deficits and sensorimotor, emotional, and cognitive performances were assessed at the 10th, 17th, and 31st days post-stroke. Our results demonstrated that Ct-PE ameliorated neurological deficits, forelimb using asymmetry, and reduced slip rates of the affected limbs at all time points, while this effect of St-PE was observed only on the 10th day. Similarly, Ct-PE for 28 d promoted spatial learning and working memory, but St-PE did not. Differently, ischemic mice in both St-PE and Ct-PE groups exhibited increased exploration behavior in the open field, light-dark box and elevated plus maze, and less immobile behavior during the tail suspension at all the time points. Our findings indicated that Ct-PE improved sensorimotor and cognitive dysfunctions after cortical ischemia in a time-dependent manner, but St-PE appeared to have greater therapeutic potential on anxiety and depression.