Opposite effects of stressful experience on memory formation in males versus females

It has become increasingly clear that males and females differ even more dramatically than we previously thought. Not only do they exhibit differing responses to stress and environmental experience, but they can also respond in opposite directions. In rats, it has been shown that exposure to an acute stressful event can enhance subsequent learning in males while dramatically impairing learning in females. These opposite effects of stress on memory formation are accompanied by similarly opposite effects on neuroanatomical measures, such as dendritic spines in the hippocampal formation. Moreover, these opposite effects of stress are mediated by different hormonal systems between the sexes. These unique responses to stressful experience in male versus female rats may be used to model sex differences in mental illness, such as those that exist for depression and posttraumatic stress disorder.