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Exposure to stress activates both the hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS). A growing body of research points to the contribution of sex hormones (testosterone, estrogen, and progesterone), the end products of the hypothalamus-pituitary-gonadal (HPG) axis, in modulating stress reactivity. The present study aimed at investigating the potential modulating role of sex hormones on HPA and SNS reactivity to psychosocial stress. The reactivity, induced by the Trier Social Stress Test, was analyzed by measuring the levels of cortisol and alpha-amylase (markers for SNS activity) in four saliva samples each of 21 men and 37 women (17 not using oral contraceptives and in their luteal phase, and 20 women using oral contraceptives). In addition, basal sex hormones were sampled prior to the psychosocial stress exposure. Results revealed that controlling for testosterone, estrogen, and progesterone diminished the impact of stress on cortisol reactivity and on alpha-amylase reactivity. Moreover, controlling for sex hormones also diminished the differential pattern of cortisol reactivity in each experimental group among responders. Furthermore, correlation analyses revealed differences between groups in the association between sex hormones and alpha-amylase. The present findings indicate a modulatory role for sex hormones in HPA and SNS reactivity and emphasize the need for control of sex hormone fluctuations when examining cortisol and alpha-amylase reactivity to stress.

Sex differences in object location memory have been widely studied, with mixed results. The role of attention in mediating the female advantage in object location memory has not been clearly understood yet. Two experiments, involving 181 participants and using an actual object array, were conducted in the present study to examine two learning conditions: incidental and intentional. In each experiment, participants were randomly assigned to divided versus full attention conditions. The study also examined memorizing location-maintained and location-exchanged objects. In both experiments, in both incidental and intentional learning conditions, women outperformed men in memorizing location-exchanged objects in the full but not in the divided attention condition. These findings confirm and extend previous ones concerning the conditions under which the female advantage in the detection of change in an array of objects occurs. The findings are discussed within an evolutionary conceptual framework.