Sex and Stress Influences on Emotional Memory for Gist and Detail

Résumé du livre

Emotional material tends to be better remembered than neutral material. Evidence now documents sex-related influences on the neurobiology of emotional memory, and the well-documented effects of stress hormones on memory appear to depend upon sex hormone levels. Some studies demonstrating sex influences on emotional memory have focused on the retention of central information (gist) and detail. However, these early studies did not account for the influence of menstrual cycle phase, hormonal contraceptive use, or post-training stress. These experiments were designed to investigate factors influencing gist and detail memory in emotional stimuli. The results of experiment 1 indicate that hormonal contraception use alters memory for gist and detail from an emotional story. Experiment 2 extended the findings from experiment 1 to reveal that sex and menstrual cycle phase at encoding also influenced memory for gist and detail from an emotional story. Together, experiments 1 and 2 suggest that biological sex and endogenous sex hormones modulate memory for emotional gist and detail. Experiment 3 explored the generality of this phenomenon by testing gist and detail memory in men and women on and off hormonal contraception using a new emotional image paradigm. These findings suggest that some of the sex-related gist and detail memory patterns generalize to another paradigm. However, this experiment also suggests that a story paradigm may be ideal for bringing sex influences on memory to light. Experiments 4 and 5 tested differences in hormone responses to stressors and the influence of post-training stress on memory for emotional gist and detail. Experiment 4 showed that compared to naturally cycling women, women on hormonal contraception had blunted salivary alpha amylase responses and cortisol responses to different stressors. Experiment 5 replicated these cortisol findings and further showed that post-training stress modulated memory for emotional gist and detail differently in women on and off hormonal contraceptives. The most consistent effect obtained across all studies was an enhancement of memory for details in naturally cycling women exposed to emotional stimuli during the high-hormone (luteal) phase of the menstrual cycle. These findings indicate that sex, menstrual cycle phase, and hormonal contraceptive use differentially influence memory for gist and detail from different emotional memory paradigms; additionally, post-training stress affects memory for gist and detail differently in women on and off hormonal contraceptives. These findings have important implications for studies of the neurobiology of emotional memory and may provide insight into disorders of emotional memory that disproportionately affect women. More generally speaking, the findings from this dissertation provide compelling evidence that in studies of emotional stress and memory, it is imperative that researchers pay attention to sex and sex hormone status of the participants.