Stress affects sleep. Acute as well as chronic stress leads to longer sleep onset latency, less slow wave sleep and worsened sleep efficiency. Sleep disturbances are an important risk factor for stress-related diseases such as burnout or depression. In addition to the impact on health, disturbed sleep has adverse effects on cognition. In particular slow wave sleep, which is reduced after stress, is essential for successful consolidation of newly learned information as well as for optimal cognitive performance the next day. Moreover, stress and cortisol modulate memory processes.

In spite of the clinical importance and the pertinence of stress-related learning processes in everyday life, the behavior, physiological as well as molecular mechanisms of the association between stress, sleep and memory are virtually unknown.

In our studies we focus on the influence of laboratory stressors or everyday stressors on sleep and memory consolidation during sleep on a behavioral, physiological and molecular basis.

We expect that the stress level on the psychological as well as the physiological levels (cortisol, heart rate variability) affect objective (sleep EEG) as well as subjective sleep parameters and cognitive performance. Consequently, we hypothesize that a higher chronic stress-level is associated with worse sleep quality, higher cortisol levels as well as lower performance in cognitive tests. Stress effects on sleep and cognitive tasks are further influenced by the level of perseverative cognitions (rumination, worrying) and are modulated by genetic variations that are associated with the reaction to stress and memory. Besides the theoretical and practical importance of this line of research, the results are also of great clinical relevance.