Stress Varies Along the Social Density Continuum

Abstract

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.

Sociodemographic Influences on Perceived Stress during Pregnancy: Results from the CCREOH Environmental Epidemiologic Study, Suriname

“…High population density, social density, and spatial density are associated with experiences of noise nuisance from neighbors and traffic; crime; and violence [ 29 – 31 ]. High population density may affect interpersonal relationships and mental health in the general population [ 29 , 31 , 32 ], including pregnant women in Paramaribo. Paramaribo is the smallest district in terms of land area, 182 km 2 , but has the largest population in Suriname (240,924).…”

Lack of Social Support and Its Role on Self-Perceived Health in a Representative Sample of Spanish Adults. Another Aspect of Gender Inequality

“…There are theories that suggest that social support is associated with the modulation of the hypothalamus-hypophysis axis and with neurotransmitters of the autonomic nervous system, such as oxytocin and vasopressin. This would reduce anxiety and stress and increase the feeling of security, which would improve self-perceived health [ 22 , 58 , 59 ].…”

The social network: Neural control of sex differences in reproductive behaviors, motivation, and response to social isolation

“…Social isolation induces severe stress in social species and might even be life-threatening [ 4 , 5 , 121 , 122∗∗ , 123 , 124 ]. In rodents, social isolation, during either adolescence or adulthood, was shown to dramatically disrupt behavior and brain function, in a sex-specific manner [ 125 ].…”