Individual differences in associative fear learning

The objective of this dissertation was to gain a better understanding of individual differences in fear learning. While following a traumatic event, individuals strongly differ in their vulnerability for or resilience to developing anxiety related disorders, this is often ignored in research and theory. As learned fear associations lie at the root of anxiety disorders, fear-conditioning is a successful laboratory paradigm for experimental research on anxiety. In this dissertation, we aimed to study a) individual variation in fear learning, b) whether the distinct adaptive or maladaptive fear-learning trajectories resemble common response patterns to real-life threat and c) whether the variation in fear learning is associated with individual differences in personality trait standings or a dysfunctional emotional processing style (worry). The overarching goal was to test the translational value of the fear-conditioning paradigm as a model for understanding individual differences in abnormal anxiety. Fear was measured as a multidimensional response including subjective and psychophysiological responses. The results presented evidence for heterogeneity in associative fear learning and provide indications for potentially adaptive and maladaptive fear-learning mechanisms. Maladaptive fear learning was tentatively related to anxiety risk traits. The current findings partly support the utility of the fear-conditioning paradigm as a translational model for understanding anxiety disorders. We used novel methodological and analytical approaches that may inspire further study of ‘intermediate phenotypes’ that underscore maladaptive fear. Advancing knowledge on the diverse courses of fear learning and its determinants may foster our understanding of anxiety-related disorders and sharpen future targets for improving clinical interventions.