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

本数据集对应的手稿摘要如下：「已有明确研究证实，认知刺激、体育锻炼与社会参与可延缓年龄相关性认知衰退。但仍有若干关键问题有待解决：同年龄段个体间认知损伤程度差异显著，如何识别最能从晚年干预中获益的受试者，便是其中之一。环境丰富化（Environmental Enrichment, EE）是解决该问题的极具价值的手段之一。
本研究以12月龄成年大鼠的测试表现作为界值，根据莫里斯水迷宫（Morris Water Maze）的测试成绩，将21月龄老年大鼠分为训练阶段的优（BL）、劣（WL）学习组，以及探测阶段的无认知损伤（NI）与认知损伤（I）组。随后对老年大鼠实施为期12周的环境丰富化饲养或标准饲养（standard housing, SH），并再次进行测试。
12周后，标准饲养组大鼠的空间学习记忆能力出现衰退，而所有接受环境丰富化饲养的大鼠均从中获益，只是获益方式存在差异：具体而言，在环境丰富化干预前被归入优学习组与无认知损伤组的动物，其表现仍可媲美成年大鼠（表现得以保留）；而至关重要的是，干预前被归入劣学习组与认知损伤组的动物，其表现得到显著改善，最终达到成年大鼠水平（表现得以提升），尽管它们在此期间进一步衰老。
环境丰富化似乎可使优学习组大鼠保留空间搜索策略，劣学习组大鼠优化空间搜索策略；同时使无认知损伤组大鼠保留对逃匿位点的聚焦式持续搜索，认知损伤组大鼠的该类搜索能力得到提升。本研究结果表明，晚年实施环境丰富化，可在认知仍保留完好的动物中阻止空间学习记忆能力衰退，并在已出现认知损伤的动物中激活其残余功能储备。未来研究应聚焦于个体化定制的刺激方案，以提升干预效果并进一步阐明其潜在机制。」
如需使用本数据集，请引用：https://doi.org/10.1016/j.exger.2020.111225