The purpose of this study is to investigate the role of a one-time intranasal administration of the oxytocin, vasopressin, or placebo on prosocial decision making such as cooperation and altruism in a healthy population of student controls.

Inclusion Criteria:

• healthy controls

Exclusion Criteria:

• Past or present psychiatric, neurological, endocrinological or severe chronic medical illness.
• Use of medications or drugs that would interfere with study results. This includes steroids, medications for psychiatric symptoms like anxiety or depression, stimulants, and medications for high blood pressure. Participants will be asked to tell the investigators of any medications or drugs that they are taking. The investigators will consider the drug interactions with oxytocin and vasopressin prior to study, and participants will not be able to participate in the study if the drug interactions could be dangerous.
• history of drug or alcohol addiction
• Pregnancy or Nursing Status: Because of the risk to an unborn fetus or infant, women who are pregnant or nursing are excluded from this protocol. All females will have a pregnancy test performed no more than 24 hours before each drug administration and will not be able to participate if the pregnancy test is positive.