Genomic and non-gemonic cortisol effects on memory retrieval dependent on sex hormone status

• Applicant: Professor Dr. Christian Josef Merz
• Subject Area: Biological Psychology and Cognitive Neuroscience
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 420772472

Stress and the accompanying increase in the stress hormone cortisol lead to impairments in memory retrieval, which exert distinct effects in daily life, for example in exams or in court. In the last years, it was emphasized that fast, non-genomic cortisol actions (starting within minutes after exposure to stress) complement slow genomic cortisol actions (beginning one hour later) and lead to impaired memory retrieval in both cases. Surprisingly, there are only few studies in humans investigating the involved neural underpinnings of memory retrieval, but restricted to non-genomic cortisol effects. In addition, previous studies only included men, thus, there is no existing evidence on the involved brain structures in women. Due to different sex hormone concentrations, attention has to be paid in women not only to the time within the menstrual cycle, but also to the intake of oral contraceptives (OC). In particular, it has been shown that stress and cortisol effects on various learning and memory processes are either not detectable in OC women or in the opposite direction as compared to men. Accordingly, it is extremely important to investigate different women groups in order to contrast sex hormone effects with direct OC effects and a general sex effect. In the present functional magnet resonance tomography study, the neural signature of non-genomic and genomic cortisol effects on memory retrieval should be characterized. In addition to men, different women groups with varying sex hormone levels should be compared: free-cycling women either tested in the early follicular phase or the luteal phase of the individual menstrual cycle as well as women taking OCs. Twenty-four hours after intentional encoding memory retrieval should take place either after intake of placebo or cortisol (20mg). Furthermore, it is intended to identify possible factors (e.g. hippocampal volume or sex hormone concentrations) associated with individual differences in the amount of memory retrieval impairment and its modulation.The results of this study can contribute a lot to a better understanding of the neurobiological underpinnings of stress hormone induced memory deficits. In addition, important clues regarding clinical application fields are expected, particularly concerning mental disorders such as posttraumatic stress disorder, whose stress-associated memory phenomena are well described.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Oliver Tobias Wolf