Relevance of context-dependent extinction processes for the development of experimentally induced intrusions

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Intrusive re-experiencing of a traumatic event is a key symptom of posttraumatic stress disorder (PTSD). Classical conditioning processes, which lead to the association of neutral stimuli with aversive consequences during the trauma, are assumed to contribute to the development of intrusive memories. Here, dysfunctional short- and long-term extinction of conditioned responses seems to be especially relevant. At the same time, contextual information concerning the traumatic event is poorly stored in autobiographical memory. Laboratory studies in PTSD furthermore indicate a deficient modulation of extinction by contextual information. This might explain the enhanced responses towards trauma associated cues in safe contexts. However, there are no studies investigating if context-dependent extinction processes predict the occurrence of intrusive re-experiencing. Additionally, there are only few insights about the influence of basic differences in the discrimination of contextual information and in cognitive emotion regulation on context-dependent extinction processes and the development of intrusions. As the investigation of these associations in clinical samples is only possible with sophisticated longitudinal designs, the trauma-film paradigm constitutes an ecologically valid and efficient alternative for the investigation of such research questions in healthy samples.Sixty-seven healthy females are to be investigated in this functional magnetic resonance imaging (fMRI) study. Before participating in a conditioning paradigm measuring context-dependent extinction processes and their neural basis, tasks for assessing behavioral pattern separation as well as the neural correlates of cognitive emotion regulation will be conducted. Afterwards, aversive film-clips will be presented to the participants during the trauma-film paradigm, and experimentally induced intrusive re-experiencing will be assessed during the following week. The main question of this study addresses the potential prediction of developing experimentally induced intrusions by context-dependent extinction processes and related activation of the fear and extinction circuit. Furthermore, the effect of behavioral pattern separation as well as immediate and prolonged effects of cognitive emotion regulation will be studied. The results of this study might contribute to a better understanding of relevant factors influencing the development of intrusive re-experiencing after traumatic events and its underlying mechanisms. In the long term, these findings might help to optimize preventive interventions as well as treatments for PTSD.