中国科学院心理健康重点实验室知识库

摘要创伤后应激障碍(Post-traumatic stress disorder，PTSD)是指个体在经历或者目睹对生命有威胁或严重伤害的创伤事件之后导致的长期持续的精神疾患。在众多PTSD的影响因素中，社会因素发挥着重要的作用，其中社会交往被认为是决定个体在经历创伤事件之后是否出现心理健康问题最重要的心理社会因素之一，理解社会环境的作用有助于更好的认识PTSD。先前的研究发现创伤事件能够影响个体的社会关系，但是创伤事件是促进个体适应性的亲社会行为增加还是会损伤个体原本的社会联结还不清楚。本研究以社会性较高的大鼠为研究对象，采用纵向分析的方法考察急性应激之后群居大鼠(n=16)社会结构的动态变化。结果发现，能够诱发PTSD样症状的单程长时应激(SPS, single prolonged stress)会长期影响群居大鼠的社会结构。应激后的当天晚上大鼠被动社会交往行为增加(例如，聚集在一起休息)，而主动社会交往行为减少(例如，嗅闻、追随、打架、相互理毛等等)。应激过后的第二天，大鼠开始重建自己的社会网络以适应环境的改变，各项异常的社会指标包括集群个数、单只个数、社会距离和主动社会交往时间有恢复的趋势。尽管如此，在行为测试阶段，异常的社会结构依然存在，主动/被动社会行为的增加或减少受当天行为测验性质的影响，例如，诱发焦虑状态的行为测试会导致群居大鼠进行积极社会交往的时间减少，整个社会团体中单只个数增加。综上所述，SPS会导致群居大鼠的社会结构长期存在异常，大鼠社会行为的增加或减少并不是一成不变的而是依赖于PTSD样症状的发展以及创伤后面临的各种挑战的性质。

Abstract: Post-traumatic stress disorder (PTSD) is a mental disorder that involves the development of long-lasting symptoms following exposure to a traumatic event.Social interaction is considered as one of the most important psychosocial factors thatdetermine whether an individual will have mental health problems following stressorexposure. Descripting the social environment around an individual may be benefit to better understand PTSD. Stress has a profound impact on individual’s social responses. But whether a traumatic event shares by a social group promotes adaptive social behaviors or disturb the original social network are not yet clear. In the present study, we thus investigated how single prolonged stress (SPS) which can induce PTSD-like symptom impacts the spatiotemporal social structure within a large crowd of co-habituated Sprague-Dawley rats (n=16). The results showed that SPS induced a significant increase in passive social behaviors (huddling behavior) and a decrease in active social behavior (e.g. sniffing, following, fighting, allogrooming) immediate aftermath of following stress. Although rats started to reconstruct their social structure in order to adapt to the environmental change and all social abnormalities started to return to the control level during the following days, the abnormities of the social structure still existed during a subsequent series of behavioral tests. Both active and passive social behaviors of the stressed rats appreciably changed, the direction of which depended on the nature of a specific behavioral test. We concluded that rats cannot sufficiently reverse SPS-induced long-term social structure abnormalities even though forced post-stress co-habitation and it is inappropriate to suggest a uniform or generalized stress-induced increase or decrease in social network behavior because changes in this behavior are critically dependent on the nature of the PTSD developmental stage.