Exogenous effects of oxytocin in five psychiatric disorders: a systematic review, meta-analyses and a personalized approach through the lens of the social salience hypothesis.

Oxytocin (OT) has been implicated in various aspects of social behaviors. During the past decades there has been a surge of interest in the therapeutic potential of OT in psychiatric disorders, especially those characterized by social deficits, which the available therapeutic agents, cannot fully target. This systematic review and meta-analysis examines available evidence for the therapeutic role of OT in five psychiatric disorders characterized with difficulties in social abilities: autism spectrum disorder, schizophrenia, post-traumatic stress disorder, mood disorders and borderline personality disorder. For each disorder, we review the sample size, gender distribution and single versus long-term effects of OT. Moreover, we examine effects of OT through the lens of the social salience hypothesis, in order to identify individual characteristics and contexts that may affect the response to OT, across the disorders. We show that OT has diverse effects depending on symptoms and context. The meta-analyses revealed a small effect size of OT efficacy in schizophrenia and repetitive behaviors in ASD. Finally, we discuss shortcomings and provide recommendations for future research.