Stress, sex, and motivated behaviors.

Stress is a major risk factor for development of psychiatric disorders such as depression and development of substance use disorder. Although there are important sex differences in the prevalence of these disorders, most preclinical models used to study stress-induced disorders have used males only. Social defeat stress is a commonly used method to induce stress in an ethologically relevant way but has only recently begun to be used in female rodents. Using these new female models, recent studies have examined how social defeat stress affects males and females differently at the behavioral, circuit, and molecular levels. This Mini-Review discusses sex differences in the effects of social defeat stress on social behavior and drug-seeking behavior as well as its impact on the mesolimbic dopamine system and the highly connected region of the bed nucleus of the stria terminalis.