The relationship between stress induced cortisol levels and memory differs between men and women

Epidemiological as well as experimental studies in elderly subjects have suggested that postmenopausal women are more susceptible to the memory impairing effects of elevated cortisol levels than elderly men. Little is known however about gender differences in the susceptibility to acute stress in young subjects. In the present study a total of 58 healthy young subjects learned a word list, with recall being tested after a brief distraction task. Twenty-two subjects had to learn the list after exposure to a psychosocial stressor (Trier Social Stress Test: TSST), while the remaining subjects served as controls. Free cortisol was determined via saliva samples taken before and 10 minutes after stress. Subjects exposed to the stressor, did not show impaired memory performance per se when compared to the control group. However the cortisol increase in response to the stressor was negatively correlated (r=-0.43, P<0.05) with the memory performance within the stressed group (i.e., subjects showing a larger cortisol response recalling less words than subjects showing only a small cortisol increase). Additional analysis revealed, that this correlation was solely caused by the strong association observed in men (r=-0.82, P<0.05), while no association was observed in women (r=-0.05, P=ns). Our data suggests, that gender modulates the association between cortisol and memory after stress. Whether these differences reflect activational effects of sex steroids or developmentally-programmed sex differences awaits to be determined.