Disruption of social bonds induces behavioral and physiological dysregulation in male and female prairie voles.

The social disruption of losing a partner may have particularly strong adverse effects on psychological and physiological functioning. More specifically, social stressors may play a mediating role in the association between mood disorders and cardiovascular dysfunction. This study investigated the hypothesis that the disruption of established social bonds between male and female prairie voles would produce depressive behaviors and cardiac dysregulation, coupled with endocrine and autonomic nervous system dysfunction. In Experiment 1, behaviors related to depression, cardiac function, and autonomic nervous system regulation were monitored in male prairie voles during social bonding with a female partner, social isolation from the bonded partner, and a behavioral stressor. Social isolation produced depressive behaviors, increased heart rate, heart rhythm dysregulation, and autonomic imbalance characterized by increased sympathetic and decreased parasympathetic drive to the heart. In Experiment 2, behaviors related to depression and endocrine function were measured following social bonding and social isolation in both male and female prairie voles. Social isolation produced similar levels of depressive behaviors in both sexes, as well as significant elevations of adrenocorticotropic hormone and corticosterone. These alterations in behavioral and physiological functioning provide insight into the mechanisms by which social stressors negatively influence emotional and cardiovascular health in humans.