Graphical Abstract Text
The presence of a non-conditioned unfamiliar same-sex rat completely ameliorates conditioned fear responses to an auditory conditioned stimulus in rats. The present study demonstrated that naloxone (but not haloperidol, SR49059, or atosiban) blocks this social buffering of conditioned fear responses. The blockade of social buffering was accompanied by decreased c-Fos expression in the nucleus accumbens, anterior cingulate cortex, and insular cortex.