Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Ave., Room 860, Toronto, Ontario M5G 1X5, Canada.
Neuropharmacology. 2013 Jan;64:283-93. doi: 10.1016/j.neuropharm.2012.06.054. Epub 2012 Jul 6.
Social context affects brain function but our understanding of its neurobiology is at an early stage. The mere presence of one individual can alter the cognitive capacities of another and social learning has been demonstrated in many species, including the mouse. We asked several questions: 1. How can active engagement of two familiar mice in the same learning activity (co-learning) alter their memory? 2. Under which environmental conditions (aversive vs non-aversive) can we expect the memory to be enhanced, impaired, or not affected? 3. Can a genetic factor modify the co-learning effect on memory? More specifically, can co-learning correct memory deficits in autistic-like BTBR inbred mice with deficient sociability? We demonstrated that pairs of familiar inbred mice of the same or different genotypes (C57BL/6J and BTBR) that were habituated to new objects and their spatial location, had enhanced episodic memory in the spatial object recognition test, whereas individually-trained animals failed to solve this task. Notably, the co-learning effect was genotype-dependent. BTBR mice paired with BTBR cage-mates in the habituation session modestly ameliorated their performance in the object recognition test but co-learning with a familiar C57BL/6J mouse completely normalized episodic memory deficit. Next, we explored the co-learning effect on fear memory in these inbred strains. Interestingly, mice of both genotypes displayed significantly enhanced contextual fear memory once they had been conditioned together with BTBR animals. The same influence of BTBR presence was observed on cued fear memory in C57BL/6J mice, whereas a modest co-learning effect was found on cued fear conditioning in the BTBR strain. Taken together, we demonstrated for the first time the co-learning effect on cognitive capacities in mice, which can be modified by genetic background and environmental conditions. The possible implications of this methodological approach in social neuroscience are discussed. This article is part of a Special Issue entitled 'Cognitive Enhancers'.
社会环境会影响大脑功能，但我们对其神经生物学的理解还处于初级阶段。仅仅有一个个体的存在就可以改变另一个个体的认知能力，并且社会学习已经在许多物种中得到了证明，包括老鼠。我们提出了几个问题：1. 两只熟悉的老鼠在相同的学习活动（共同学习）中积极参与，如何改变它们的记忆？2. 在什么环境条件下（厌恶的还是非厌恶的）可以期望记忆增强、受损或不受影响？3. 遗传因素可以改变共同学习对记忆的影响吗？更具体地说，共同学习能否纠正自闭症样 BTBR 近交系小鼠社交能力缺陷的记忆缺陷？我们证明，习惯新物体及其空间位置的相同或不同基因型（C57BL/6J 和 BTBR）的熟悉近交系老鼠对记忆有增强的情节记忆，而单独训练的动物则无法解决这个任务。值得注意的是，共同学习的效果取决于基因型。在习惯阶段与 BTBR 笼伴配对的 BTBR 老鼠在物体识别测试中的表现略有改善，但与熟悉的 C57BL/6J 老鼠共同学习则完全纠正了情节记忆缺陷。接下来，我们在这些近交系中探索了共同学习对恐惧记忆的影响。有趣的是，一旦与 BTBR 动物一起进行条件作用，两种基因型的老鼠的情境恐惧记忆都显著增强。BTBR 存在的相同影响也观察到在 C57BL/6J 小鼠的线索恐惧记忆中，而在 BTBR 株中发现了对线索恐惧条件作用的适度共同学习效应。总之，我们首次证明了共同学习对小鼠认知能力的影响，这种影响可以通过遗传背景和环境条件来改变。本文探讨了这种方法在社会神经科学中的可能应用。本文是一个题为“认知增强剂”的特刊的一部分。
