Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.15.383489v1?rss=1 Authors: Ayash, S., Lingner, T., Ryu, S., Kalisch, R., Mueller, M. B., Schmitt, U. Abstract: Chronic social defeat (CSD) in mice has been increasingly employed in experimental resilience research. Particularly, the degree of CSD-induced social avoidance is used to classify animals into resilient (socially non-avoidant) versus susceptible (avoidant). Inspired by human data pointing to threat-safety discrimination and responsiveness to extinction training of aversive memories as characteristics of resilient individuals, we here describe a translationally informed stratification which identified three phenotypic subgroups of mice following CSD: the Discriminating-avoiders, characterised by successful social threat-safety discrimination and successful extinction of social avoidance; the Indiscriminate-avoiders, showing aversive response generalisation, and the Non-avoiders (absence of social avoidance) displaying impaired conditioned learning. Furthermore, and supporting the biological validity of our approach, we uncovered subgroup-specific transcriptional signatures in classical fear conditioning and anxiety-related brain regions. Our reconceptualisation of resilience in mice refines the currently used dichotomous classification and contributes to advancing future translational approaches. Copy rights belong to original authors. Visit the link for more info