Early life stress modulates oxytocin effects on limbic system during acute psychosocial stress

Early life stress (ELS) is associated with altered stress responsivity, structural and functional brain changes and an increased risk for the development of psychopathological conditions in later life. Due to its behavioral and physiological effects, the neuropeptide oxytocin (OXT) is a useful tool to investigate stress responsivity, even though the neurobiological underpinnings of its effects are still unknown. Here we investigate the effects of OXT on cortisol stress response and neural activity during psychosocial stress. Using functional magnetic resonance imaging in healthy subjects with and without a history of ELS, we found attenuated hormonal reactivity and significantly reduced limbic deactivation after OXT administration in subjects without a history of ELS. Subjects who experienced ELS showed both blunted stress reactivity and limbic deactivation during stress. Furthermore, in these subjects OXT had opposite effects with increased hormonal reactivity and increased limbic deactivation. Our results might implicate that reduced limbic deactivation and hypothalamic-pituitary-adrenal axis responsivity during psychosocial stress are markers for biological resilience after ELS. Effects of OXT in subjects with a history of maltreatment could therefore be considered detrimental and suggest careful consideration of OXT administration in such individuals.