In aged rats, differences in spatial learning and memory influence the response to late-life Environmental Enrichment - Balietti et al., 2021

Below the abstract of the manuscript in which data were described:
"It has clearly been demonstrated that cognitive stimulation, physical exercise, and social engagement help counteract age-related cognitive decline. However, several important issues remain to be addressed. Given the wide differences in cognitive impairment found among individuals of the same age, identifying the subjects who will benefit most from late-life interventions is one such issue. Environmental Enrichment (EE) is a particularly valuable approach to do this. In this study, aged (21-month-old) rats were assigned to a better (BL) or a worse (WL) learner group (training phase) and to a non-impaired (NI) or an impaired (I) group (probe phase) by their performance on the Morris Water Maze, using the test performances of adult (12-month-old) rats as the cut-offs. The aged rats were retested after a 12-week EE or standard housing (SH) protocol. After 12 weeks, the performances of SH rats had deteriorated, whereas all rats benefited from EE, albeit in different ways. In particular, the animals assigned to the BL and the NI groups prior to EE still performed as well as the adult rats (performance preservation) whereas, critically, the animals assigned to the WL and the I groups before EE showed such improved performances that they reached the level of the adult rats (performance improvement), despite having aged further. EE seems to induce the preservation in BLs and the improvement in WLs of spatial search strategies and the preservation in NIs and the increase in Is of a focused and protract research of the escape point. Our findings suggest that late-life EE prevents spatial learning and memory decline in still cognitively preserved animals and stimulates residual functional reserve in already cognitively compromised animals. Future research should focus on individually tailored stimulation protocols to improve their effect and afford a better understanding of the underlying processes."
For using data set, please cite: https://doi.org/10.1016/j.exger.2020.111225

以下为该数据集所依托手稿的摘要内容：
已有明确研究证实，认知刺激、体育运动与社会参与可有效延缓年龄相关性认知衰退。但目前仍有若干关键问题亟待解决：鉴于同年龄段个体间的认知损伤程度存在显著差异，识别出最能从晚年干预中获益的受试者群体便是其中之一。环境丰富化（Environmental Enrichment，EE）便是实现该目标的极具价值的手段之一。
本研究以12月龄成年大鼠的莫里斯水迷宫（Morris Water Maze）测试成绩作为临界值，将21月龄的老年大鼠在训练阶段分为优秀学习者（better learner, BL）与较差学习者（worse learner, WL）两组，并在探查阶段根据其表现分为无认知损伤（non-impaired, NI）与认知损伤（impaired, I）两组。随后，对这些老年大鼠分别实施为期12周的环境丰富化饲养或标准饲养（standard housing, SH），并再次进行认知测试。
12周饲养周期结束后，标准饲养组大鼠的空间认知表现出现衰退，而所有接受环境丰富化饲养的大鼠均获得了认知改善，只是改善路径存在差异。具体而言，在环境丰富化干预前被归入BL与NI组的大鼠，其认知表现仍可维持至成年大鼠水平（表现为认知保留）；尤为关键的是，干预前归入WL与I组的大鼠，尽管又经历了年龄增长，但其认知表现获得了显著提升，最终达到了成年大鼠的水平（表现为认知改善）。
进一步分析显示，环境丰富化可使BL组大鼠保留空间搜索策略、WL组大鼠优化该类策略；同时使NI组大鼠保留对逃逸点的聚焦且持续的搜索行为，I组大鼠则增强了此类搜索行为。本研究结果表明，晚年环境丰富化干预可在认知仍保留完好的个体中阻止空间学习与记忆能力的衰退，并在已出现认知损伤的个体中激活其残余功能储备。未来的研究应聚焦于个性化定制的刺激方案，以提升干预效果并更深入地解析其背后的作用机制。
若使用本数据集，请引用：https://doi.org/10.1016/j.exger.2020.111225