Diversified Learning Environment Alleviates Learning Impairment Caused by Contextual Stress

Abstract

Environment is capable of affecting our learning ability. Existing studies reported that learning ability can be enhanced by enriched environment and impaired by stressful context. However, it is still unclear whether diversified environment can reverse or ameliorate the learning difficulty caused by stressful context. In this study, several behavioral tasks were designed to test the role of diversified environment in active avoidance learning. In the present study, sound-cued active avoidance (two-way shuttle box) acted as learning paradigm. Multiple shuttle boxes with the identical size but different designs were employed to mimic diversified environment in learning tasks. Mild but inevitable foot shocking was adopted to increase animals stress to certain context. To quantify the depression/anxiety level of animals, open field test, forced swimming test, light-dark box test, and elevated plus maze were performed. The following findings were reported. First, diversified learning environment could improve learning ability in active avoidance, as manifested by higher successful rate and sharper learning curve. Second, elevating the stress level of animal to a certain context could noticeably reduce its performance in active avoidance learning. Third, the learning impairment attributed to stressful context can be improved by training in diversified environments. Thus, as revealed from the results, learning impairment caused by stressful context can be alleviated by diversified learning environment which may facilitate further medical and education applications.