Social dominance in rats is a determinant of susceptibility to stress

Abstract

Although stress has significant impact on brain and behavior, its effects vary between individuals. Relatively little is known about how social status contributes to individual differences in stress vulnerability. We report that stress affects social dominance tests between unfamiliar animals (living in different cages), but not familiar animals (living together). Higher-ranked animals exhibited resilience to stress, whereas lower-ranked animals displayed enhanced submissiveness. Interestingly, poorer behavioral resilience caused by a combination of stress and lower social status was associated with structural changes in synaptic connectivity in the amygdala, a brain area that encodes emotional experiences.