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bioRxiv · 10.1101/2020.05.01.072827

Shared safety abolishes the recovery of learned threat

Abstract

Social learning offers an efficient route to transmit information about threat and safety. To better isolate the processes that contribute to the efficacy of social safety learning, we developed a novel dyadic model of associative threat and extinction learning. In three separate social groups, we manipulated whether safety information during extinction was acquired via direct exposure to the conditioned stimulus (CS) in the presence of another individual (Direct exposure), via observation of other’s safety behavior (Vicarious exposure), or via the combination of both (Shared exposure). These groups were contrasted against a fourth group receiving direct CS exposure alone (Asocial exposure). Based on skin conductance responses, we observed that all social groups outperformed asocial learning in inhibiting the recovery of threat, but only Shared exposure abolished threat recovery. These results suggest that social safety learning is optimized by a combination of direct exposure and vicariously transmitted safety signals.Statement of relevance Humans, like other social animals, learn about threats and safety in the environment through social cues. Yet, the processes that contribute to the efficacy of social safety learning during threat transmission remain unknown. Here, we used a two-person approach to analyze skin conductance responses as participants engaged in a standard fear conditioning procedure (acquisition, extinction, and reinstatement). We found that during extinction, both (i) direct (conditioned stimulus) exposure in the presence of another individual and (ii) vicarious safety signals alone is sufficient to inhibit subsequent threat recovery, but that abolishing the recovery of conditioned threat responses requires a combination of both. This study has relevance for understanding how social information can optimize standard, asocial safety learning procedures to augment the effects of exposure on previously acquired fears. Thus, our work might help identify psychological and social strategies that can be used to counteract maladaptive fears in humans.Competing Interest StatementThe authors have declared no competing interest.View Full Text

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Pan, Y., Olsson, A., Golkar, A.. 2020-05-03. Shared safety abolishes the recovery of learned threat. https://doi.org/10.1101/2020.05.01.072827

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