Stress and the social brain: behavioural effects and neurobiological mechanisms

Key Points

  • The effects of stress on social behaviour depend on the timing, the duration and the type of stress exposure.

  • Social withdrawal and aggression are a typical consequence of experiencing, or having experienced, high and persistent stress levels.

  • From a developmental perspective, early stressors impose an increasing pattern of dysfunctional social behaviour, progressing from asociality (elicited by prenatal stressors) to hostility (by postnatal stressors) and to antisociality (by stressors during juvenility).

  • In humans, stress can also elicit prosocial behaviours, particularly towards ingroup members.

  • Individual differences in the effect of stress in social behaviours are partly explained by certain gene polymorphisms (for example, the monoamine oxidase A (MAOA) gene).

  • Glucocorticoids mediate, at least in part, the effects of stress on social behaviours.

  • Monoamines, social neuropeptides, the corticotropin-releasing hormone (CRH) system, cell adhesion molecules and epigenetic mechanisms are implicated in the translation of stress effects in social behaviours.

  • Positive social interactions can protect individuals from the adverse effects of stress.


Stress often affects our social lives. When undergoing high-level or persistent stress, individuals frequently retract from social interactions and become irritable and hostile. Predisposition to antisocial behaviours — including social detachment and violence — is also modulated by early life adversity; however, the effects of early life stress depend on the timing of exposure and genetic factors. Research in animals and humans has revealed some of the structural, functional and molecular changes in the brain that underlie the effects of stress on social behaviour. Findings in this emerging field will have implications both for the clinic and for society.

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Figure 1: Social behavioural profiles emerging in response to stress exposure.
Figure 2: The social brain in humans and animals.


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This study was supported by grants from the Swiss National Science Foundation (31003AB-135710 and 31003A_152614; the NCCR 'The synaptic basis of mental diseases'), the Oak Foundation, the European Union (MEMSTICK, FP7HEALTHF2M2007201600), the Hungarian Academy of Sciences Distinguished Visiting Scientist Program and intramural funding from the Swiss Federal Insitute of Technology Lausanne (EPFL) to C.S. and ERC2011ADG294313 (SERRACO) grant to J.H. The authors thank members of their respective laboratories for their original scientific contributions to the work reviewed here.

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Correspondence to Carmen Sandi.

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Stress response

The activation of coordinated neurophysiological responses in the brain and periphery — that is, the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis — to restore homeostasis disturbed by environmental demands or stressors.


Noxious stimuli that elicit a stress response.


Individuals of the same species.

Social defeat

After confrontation between conspecific individuals, social defeat may be experienced by the losing individual. Its symptoms are submissive postures shown to the winner and the avoidance of social and aggressive contacts.


Agonistic behaviours that break behavioural 'rules' that have evolved to limit dangerous forms of aggression. They include excessive levels and displaced targeting of attack and deficient social communication.

Behavioural agitation

Rapid switches from one behaviour to another, including running around the perimeter of the cage, jumping, repeated self-grooming and/or performing repeated, stereotypy-like behaviours.

Offensive ambiguity

Increased aggression against small opponents together with decreased aggression against large opponents. It is also characterized by increased defensiveness against a background of increased offensiveness.

Instrumental aggression

A premeditated aggressive action that has a specific goal, such as material gain. It is associated with low emotional and physiological arousal, and these features also characterize animal analogues of this behaviour.

Extrahypothalamic CRH system

Neurons containing corticotropin-releasing hormone (CRH) and/or CRH receptors that have their cell bodies localized in brain regions other than the hypothalamus.

Epigenetic mechanisms

Changes in gene expression that do not arise from changes to the DNA sequence and that include alterations in DNA methylation, histone modifications and non-coding RNAs (microRNAs and long non-coding RNAs).

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Sandi, C., Haller, J. Stress and the social brain: behavioural effects and neurobiological mechanisms. Nat Rev Neurosci 16, 290–304 (2015).

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