Contextual fear learning and memory in alternative stress coping styles

Animals frequently must overcome stressors, and the ability to encode and recall these salient experiences is essential to an individual’s survival. Across many taxa, studies have documented two alternative stress coping styles (proactive and reactive) that differ in behavior, cognition, stress physiology, and underlying neuromolecular mechanisms. The role of stress in cognitive traits (e.g. learning and memory) has been well documented, however, the influence of an animal’s stress coping style on learning and memory capabilities is only beginning to be understood. Here, we developed a contextual fear learning paradigm to characterize learning and memory differences between proactive and reactive stress coping styles. Specifically, we trained zebrafish to associate an antipredatory response with a conditioned context (CS) using alarm substance as an unconditioned stimulus (US). Zebrafish with the reactive stress coping style acquired the fear memory at a significantly faster rate than proactive fish over four CS-US pairings. While both stress coping styles showed equal memory recall one day post-training with no significant difference in freezing time, reactive zebrafish showed significantly higher levels of freezing relative to proactive fish four days post-training. Altogether we find that an animal’s stress coping style is closely linked to learning and memory capabilities. Specifically, how individuals cope with stress may also promote differences in information processing, decision making, and how salient experiences are encoded and recalled (e.g. cognitive biases)