Social stress is ubiquitous in the lives of social animals. While significant research has aimed to understand the specific forms of stress imparted by particular social interactions, less attention has been paid to understanding the behavioral effects and neural underpinnings of stress produced by the presence and magnitude of social interactions. However, in humans and rodents alike, chronically low and chronically high rates of social interaction are associated with a suite of mental health issues, suggesting the need for further research. Here, we review literature examining the behavioral and neurobiological findings associated with changing social density, focusing on research on chronic social isolation and chronic social crowding in rodent models, and synthesize findings in the context of the continuum of social density that can be experienced by social animals. Through this synthesis, we aim to both summarize the state of the field and describe promising avenues for future research that would more clearly define the broad effects of social interaction on the brain and behavior in mammals.

中文翻译：

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压力随社会密度连续体而变化

社会压力在社会动物的生活中无处不在。虽然重要的研究旨在了解特定社交互动所带来的特定压力形式，但对了解由社交互动的存在和程度所产生的压力的行为影响和神经基础的关注较少。然而，在人类和啮齿动物中，长期低和长期高的社会互动率与一系列心理健康问题有关，这表明需要进一步研究。在这里，我们回顾了研究与社会密度变化相关的行为和神经生物学发现的文献，重点研究啮齿动物模型中的慢性社会孤立和慢性社会拥挤，并在社会性动物可以体验的社会密度连续体的背景下综合发现。通过这种综合，我们旨在总结该领域的状态并描述未来研究的有希望的途径，这些途径将更清楚地定义社会互动对哺乳动物大脑和行为的广泛影响。