Competing to cooperate: developing a social brain

在非人类动物中，最常见的游戏形式是“打闹游戏”或“打斗游戏”，这是一种非伤害性的竞争互动形式，在这种互动中，伙伴们相互竞争一些优势，比如能够轻轻地咬对方。存在行为机制，可以降低游戏打斗升级为严重打斗的风险；这使得游戏中反复的身体接触变得有益。当像老鼠这样的动物在幼年时期被剥夺了参与同伴游戏的机会时，它们就会发育成社会无能的成年人。我的研究表明，如果大脑的某些区域受损，比如前额叶皮层，老鼠就会表现出社交缺陷，就好像它们被剥夺了玩耍的机会。当动物在幼年时期的游戏经历发生变化时，这些前额叶皮层区域的神经元的解剖结构就会发生变化。因此，我的理论是，青少年时期的打斗游戏经验对于大脑中那些对社会能力至关重要的区域的发展是必要的。在提议的研究中，我将使用实验室老鼠来调查游戏体验的哪些方面对大脑的发展至关重要，并描述更有能力的社会大脑执行更有能力的社会行为的机制。例如，在决定如何最好地回应一个伴侣时，重要的是要考虑到他的身份和他的行为，我的数据表明，这两个方面是在前额皮质的不同区域编码的。我还将对不同灵长类动物的游戏进行比较分析，以确定不同物种之间的游戏打斗组织是否因其社会行为的复杂性而有所不同。再一次，我的初步发现表明，那些在社会中有更复杂问题需要解决的物种，在幼年时期的游戏模式似乎适合训练它们做出快速而多样的行动。这些研究将描述社会能力是如何发展的，以及青少年时期的游戏经历对这种发展的贡献。

The most common form of play in non-human animals is 'rough-and-tumble play' or 'play fighting', which is a non-injurious form of competitive interaction, where partners compete for some advantage over one another, such as being able to bite their partner gently. Behavioural mechanisms exist that reduce the risk of play fighting escalating into serious fighting; this makes the repeated bodily contact found in play rewarding. When animals, such as rats, are deprived, in the juvenile period, of the opportunity to engage in peer-peer play, they develop into socially incompetent adults. My work has shown that if certain areas of the brain are damaged, such as the prefrontal cortex, rats exhibit social deficits as if they had been deprived of play. The anatomy of the neurons in these areas of the prefrontal cortex is modified when varying the experience the animals have in play as juveniles. Therefore, I theorize that experience with play fighting as juveniles is necessary for the development of those areas of the brain that are critical for social competency. In the proposed research, I will use laboratory rats to investigate what aspects of the play experience are critical for the development of the brain and characterize the mechanisms by which a more competent social brain executes more competent social behaviour. For instance, when deciding how best to respond to a partner, it is important to take into account both its identity and its actions, and my data suggest that these two facets are encoded in different areas of the prefrontal cortex. I will also conduct a comparative analysis of play in a diverse range of primates to determine whether the organization of play fighting differs among species depending on the complexity of their social behaviour. Again, my preliminary findings suggest that those species with more complex problems to solve in their societies have patterns of play as juveniles that seem appropriate for training them to make quick and varied actions. These studies will characterize how social competence develops and the contribution made to this development by the experience of play as juveniles.