Schizophrenia is a complex and heritable disorder that encompasses several clinical symptom domains and functional impairments. Existing treatments of schizophrenia, although effective against positive symptoms, fail to benefit negative symptoms, the focus of the current protocol. One of the strategies of novel drug development depends on identifying heritable physiological deficits that mark the disease liability and are thought to occur along the causal pathway of negative symptoms. These heritable physiological deficits are often found in the biological relatives of schizophrenia proband; particularly those who have schizophrenia related personality styles [defined by schizophrenia spectrum personalities (SSP) in the diagnostic system], even though they do not have the full-blown illness. The current protocol will pilot a strategy of targeting biomarkers of negative symptoms using intranasal oxytocin in relatives of schizophrenia patients. The drug probe studies in such non-clinical sample have several advantages including the absence of other drug treatment that may modulate the response, and the lack of generalized deficits causing problems with task comprehension/engagement that may mute the therapeutic signal. In addition, finding of efficacy of the experimental drug on the target physiological deficit and the associated symptoms has clinical implications on its own rights. This is because about 25% of subjects with schizophrenia spectrum personality disorders experience serious functional impairments.

Oxytocin is an extensively used drug, which is well tolerated with few serious side effects. Several lines of evidence suggest its putative role in the treatment of negatives symptoms, particularly a lack of social drive and related symptoms.