Oxytocin and Affect Processing in Posttraumatic Stress Disorder

The investigators will use multiple methods (including Oxytocin intranasal inhalation,
neuroimaging, behavioral measures, peripheral hormone measurements) to examine how
individuals' behavior, cognition, and brain function is impacted by the neuro-hormone
Oxytocin. Specifically, the investigators plan to evaluate the influence of Oxytocin
administration on affective processing in non-trauma exposed and trauma-exposed adults (both
with and without posttraumatic stress disorder, PTSD). The investigators expect oxytocin
(compared to placebo) to positively influence affect processing in healthy subjects, as well
as among those diagnosed with PTSD. Given current literature, the investigators expect
oxytocin to elevate the processing\perception of positive-related stimuli, and reduce the
salience of aversive or un-pleasant cues. The investigators expect oxytocin to impact
participants' brain function as measured with functional magnetic resonance imaging (fMRI)
while visually processing social and affect-related stimuli, rendering brain function and
affective processing to be "more typical" or "adaptive" compared to placebo. Oxytocin's
effect on human repertoire is not necessarily direct, but can interact with the individual's
socioemotional characteristics, early life environment, and psychiatric symptoms. Therefore,
the investigators will incorporate measures that capture the various dimensions that likely
shape the effect of oxytocin.

Inclusion Criteria:

- Adults: age 18-55

- Be in good medical health

- Be cooperative with testing

- English is a language spoken in the family

- PTSD as diagnosed by a certified clinician or the research team for PTSD group.

Exclusion Criteria:

- Moderate or severe acute or chronic medical illnesses (e.g.cardiac disease, diabetes,
epilepsy, influenza).

- History of hypertension with baseline blood pressure above 160 mm Hg (systolic) over
100 mm Hg (diastolic).

- history of syncope and/or baseline blood pressure below 100 mm Hg (systolic).

- weight >300lb

- The use of some psychotropic medications will not be allowed. Females taking
contraceptive hormones will not be able to participate in the study.

- Currently breast feeding or pregnant

- For MRI ONLY: Any metal or electromagnetic implants

- For MRI ONLY: Significant hearing loss or other severe sensory impairment

- A fragile health status.

- For MRI ONLY: A history of seizures or current use of anticonvulsants

- Healthy adult controls (HC):

- Be free of both neurological and psychiatric disorders (current and past) on the
basis of self-report

- Be free of psychiatric disorders