In several animal models and in some human studies, resilience is associated with rapid activation of the stress response and its efficient termination24. Resilience is associated with the capacity to constrain stress-induced increases in CRH and cortisol through an elaborate negative feedback system, involving optimal function and balance of glucocorticoid and mineralocorticoid receptors3,24,25. Studies suggest that the HPA disturbances that are associated with PTSD are different from those that are associated with major depression24. Of note, animals that adopt active responses to environmental threat show lower glucocorticoid responses than those that adopt passive responses, although the relationship between coping strategies and HPA axis activity is probably complex (for example, see REF. 26). In humans these two personality types have been linked with risk for different sets of disorders, demonstrating that the relationship between health and the functioning of the stress response system is complex27. In addition, dehydroepiandrosterone (DHEA), which is also released in response to stress, has antiglucocorticoid effects in the brain. Higher DHEA sulphate/cortisol ratios in individuals undergoing rigorous military survival training were associated with lower dissociative symptoms and
