It has long been established that interpersonal relationships can have a profound impact on health and well-being. Yet, the investigators are still learning about the complex biological processes that contribute to positive social interactions and the ability to develop and maintain social relationships. Recent research has begun to focus on oxytocin, a neuropeptide that is naturally produced in the hypothalamus, because administration of this neuropeptide has been associated with increased trust, generosity, empathy, cooperation, memory of social stimuli (e.g., faces), and brain activity in neural regions associated with social and emotional processes. To date, several aspects of oxytocin's effects on social behavior have been unexplored. As such, the overarching goal of this project is to examine the effects of intranasal oxytocin on several tasks involving social processes. In addition, the investigators will explore associated neural activity through functional magnetic resonance imaging (fMRI). Understanding how oxytocin influences these aspects of social functioning will help to inform research that has begun to establish the potential for use of this neuropeptide in education as well as psychiatric disorders such as autism spectrum disorders and schizophrenia that are characterized by social deficits.

The investigators hypothesize that compared to placebo, oxytocin will improve deception detection, increase empathy and altruism, and enhance responses to photo stimuli of primary caregivers. These effects will manifest in behavioral and neural activity. It is also hypothesized that main effects will not be found for oxytocin, but rather, analyses of relevant moderators will elucidate these findings.

Inclusion Criteria:

• 18-30 years of age
• Healthy (see below)
• Fluent in English
• Right-handed

Exclusion Criteria:

• Women who gave birth in the last six months, are currently pregnant, planning to become pregnant in the next 6 months, or currently breastfeeding women
• Symptoms of runny nose due to allergies/cold or other reason
• Current restricted fluid intake for any reason
• Heart disease
• Hypertension
• History of myocardial infarction
• History of cardiac arrhythmia
• Kidney or liver disease
• Vascular disease
• Epilepsy
• Migraine
• Asthma
• Nephritis
• Diabetes and other endocrine diseases
• Frequent or unexplained fainting
• History of stroke
• Aneurysm or brain hemorrhage
• Active psychiatric diagnosis
• Current psychopharmacologic treatment
• Drug or alcohol abuse
• Medical or neurological illness
• Regular use of medication (e.g., vasoconstrictive medications)
• Medication intake less than 2 weeks prior to study (5 weeks for fluoxetine) including daily non-steroidal anti-inflammatory drugs
• Smoking more than 15 cigarettes a day
• Consumption of any alcoholic beverages in the past 24 hours will be excluded
• Elevated blood pressure (>135/90)
• Low blood pressure (<90/55)
• Body temperature >100.1 F
• Left-handed
• Claustrophobia
• Presence of metal in their body