Forty subjects with bipolar disorder who are not receiving a mood-stabilizing medication for the treatment of their illness will participate in this study. The study aims to evaluate how decision-making is affected by treatment for bipolar disorder. Prior to beginning treatment, patients will complete questionnaires and a one-hour computer-administered assessment of decision-making. Differences between pre-post decision-making outcomes will be evaluated to examine whether the neuroeconomic concepts of risk aversion, loss aversion, risk tolerance and delay discounting are affected by treatment.

The overall goal of this study will be to identify whether decision-making in people with bipolar disorder is affected by treatment. Specifically the investigators will compare decision-making characteristics among bipolar patients prior to treatment with how these decision-making characteristics change over the course of 6 weeks of standard medication therapy for bipolar disorder. A total of 6 decision-making tasks and one control task will be administered via computer to eligible subjects. The investigators will evaluate decision-making under varying conditions of reward, risk, and uncertainty and over time. The investigators hypothesize that decision-making will improve across these assessments after 6 weeks of treatment.

Participation in this study will require three study visits over 6 weeks. Subjects will be evaluated with the Structured Diagnostic Interview for DSM-IV to confirm diagnosis. They will also be administered the Hamilton Anxiety and Depression Rating Scales. Eligible subjects will then complete questionnaires related to their symptoms as well as decision-making and risk-taking, including: the Barratt Impulsiveness Scale, the Spielberger State-Trait Anxiety Inventory, and the Flinders Decision-making questionnaire. The Montgomery-Asburg Depression Severity scale to assess changes in depression symptom severity and the Young Mania Rating Scale to assess changes in manic symptom severity, will be conducted at screening, baseline, and endpoint. Patients will also be given the Childhood Trauma Questionnaire at baseline visit, to assess for a history of childhood trauma. The subjects will then complete the computer-generated decision-making tasks. Upon completion, the study physician will initiate standard-of-care treatment with a mood stabilizer (either lithium, valproate, or lamotrigine). Standard-of-care laboratory testing and psychiatric follow-up will be performed during the patient's study participation. After six weeks of treatment with a mood stabilizer, patients will again complete the decision-making computerized assessment.

Inclusion Criteria:

1. Male or female, age 18-65
2. Primary DSM-IV TR Diagnosis of Bipolar Disorder, type I, II or NOS.
3. Ability to visually read and understand English language
4. Not currently taking any mood stabilizer or antipsychotic medication.
5. Women of reproductive potential must be willing to take a medically approved form of birth control throughout the duration of the study.

Exclusion Criteria:

1. Meet criteria for substance abuse or dependence within three months of the screening visit.
2. Presents with a clinically significant suicide risk, as assessed by a study physician.
3. Presence of any unstable or central nervous system-related medical illness that would interfere with cognition or participation.
4. Women who are currently pregnant or lactating, or plan to become pregnant during the study.

Adverse events were collected throughout the duration of the study.