Social cognition impairment is critical to the pathology and morbidity of a number of psychiatric disorders, including the schizophrenia spectrum, the autism spectrum and the personality disorders, thus representing a dimension consistent with RDoC. As such, this study aims to a) further characterize the unique deficits in social cognition (recognition and interpretation of social cues and representation of thoughts, intentions, and feelings of others) across disorders, including the schizophrenia spectrum (which includes schizophrenia, SCZ, schizoaffective disorder, SAD, bipolar disorder, BD, and schizotypal personality disorder, SPD), the autism spectrum disorders (ASD), and borderline personality disorder (BPD) compared to healthy controls (HC); b) assess the effect of intranasal oxytocin (OXT) as a regulator and novel treatment of social cognition impairment in these disorders; and c) enhance our understanding of the specificity and exact mechanisms of impairment to inform the accurate dosing of OXT required to modulate social cognition in these disorders and identify a model of optimum social cognitive function. Addressing these questions will further catalyze research into a model of optimum social cognitive activity, and accelerate industry development of agents suited to routine clinical administration.