1. The patient meets DSM-IV criteria for type I bipolar disorder, manic or mixed, or depressed.

2. The patient has an index Young Mania Rating Scale (YMRS)total score \>15 or Montgomery Asberg Rating Scale (MADRS) total score \>20.

3. The patient is between 15 and 55 years old.

1. Healthy subjects will be between the ages of 15 and 55 years.

2. Healthy subjects will have no history of any Axis I psychiatric disorder.

3. Healthy subjects will have no first-degree relatives with affective or psychotic disorders.

Neurofunctional and Neurochemical Markers of Treatment Response in Bipolar Disorder