Oxytocin enhances acquisition in a social trust task in mice, whereas both oxytocin and its antagonist block trust violation learning.

The complex effects of the neurohormone oxytocin (OT) on socio-cognitive phenomena have recently been proposed to be complementary with safety learning, where a stimulus acquires safety-predicting properties when it predicts non-occurrence of an aversive event. OT may enhance salience of safety stimuli and promote positive social behavior, such as trust, by reducing anxiety and stress. Complementary, OT may reduce the ability to modulate previously learned behaviors based on new, contradicting information. This occurs through its attenuation of prediction error (PE)-the discrepancy between expectations and actual outcomes. In the current study, we modulated OT receptor (OTR) activity by administering an agonist (OT) and antagonist (cligosiban, CL), and subjected male and female mice to our social transmission of food preference (STFP) protocol to assess social safety learning. STFP is based on the observation that food neophobia of rodents is attenuated when a conspecific signals the safety of the food. We used safe food preference as putative murine homologue of human trust acquisition, and modeled trust violation (PE) using lithium chloride (LiCl)-induced food aversion after social interaction. In males, results revealed that OT enhanced trust acquisition, whereas both OT and its antagonist CL similarly blocked trust violation learning. None of the manipulations affected female behavior. Our findings highlight the complexities of OT's role in social behavior, emphasizing caution in therapeutic manipulations of this system.