Is full physical contact necessary for buffering effects of pair housing on social stress in rats?

▶ Mere exposure to the cage and bedding used by a familiar pairmate did not prevent an increase in anxiety after social defeat. ▶ Separation from a familiar pairmate by a wire mesh did also not prevent increased anxiety. ▶ Visual, auditory, and olfactory contact with a familiar pairmate was not sufficient to reduce the anxiogenic effect of social defeat. ▶ Full physical contact is necessary for the emergence of the buffering effect of pair housing on social stress.