Deciphering the Role of Oxytocin in Motivation: an fMRI Study

Inclusion Criteria: * Male * 20-35 years of age at the time of screening * Right-handedness * Non-smoking * No current or past history of neurological or psychiatric illness, including substance abuse or dependence * No acute medical illness * Written informed consent obtained from subject Exclusion Criteria: * Female * Left-handedness or ambidextrous * Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data * Known allergies to oxytocin or to preservatives in the nasal spray * Participants who exhibit nasal obstruction or upper-respiratory tract infection at the time of scanning or report the use of intranasally administered medications for up to two weeks prior to screening * Participants unable to tolerate the scanning procedures or would be unfit for scanning purposes (e.g. metal implants, claustrophobic, unable to lie still for the duration of the scan) * Any current or past history of medical, neurological, or psychiatric illness or family history of psychiatric or neurologic disease in first-degree relatives * Neurological illness, abnormal MRI (except if due to technical factors) * Acute or uncorrected medical illnesses, including history of hepatic or renal dysfunction. * Participants currently taking medications including any treatment, current or past with antipsychotics, mood stabilizers, isoniazid, glucocorticoids, psychostimulants and psychostimulant appetite suppressants, or centrally active antihypertensive drugs (e.g., clonidine, reserpine). * Treatment within six months with any of the following: hormone use (testosterone, DHEA), antidepressants, opioid drugs. * Treatment within one month with sedative hypnotic medications (benzodiazepines, barbiturates), or over the counter sleeping aids * Current or past history of substance abuse or dependence * Any reported lifetime use of any category of illicit drugs * Positive urine drug screen