Aim: The purpose of the study is to characterize the at-risk phases preceding a first episode of bipolar disorder and of schizophrenia, and to identify clinical and biological predictors of the disease development.

Hypothesis a: Over 6-24 months, 25% of at-risk youth will develop the full manifestations of Bipolar Disorder (BPD) or schizophrenia.

Hypothesis b: The symptoms utilized for characterizing the at-risk phase of BPD will differentiate between individuals developing BPD and schizophrenia.

Prospective, naturalistic, cohort study aiming to characterizing the bipolar and psychotic prodrome thoroughly with a variety of clinical and biological measures.

Inclusion Criteria:

1. Age: 12-18 years;
2. Sex: male or female;
3. Race/ethnicity: no restrictions;
4. Definite or suspected chart diagnosis of BP-II, BP-NOS, cyclothymia, MDD, depressive disorder NOS, dysthymia or mood disorder NOS, schizophrenifiorm disorder or psychotic disorder NOS;
5. Subject and parent (if subject<18) willing and able to provide written, informed consent/assent.

Exclusion Criteria:

1. Estimated Premorbid IQ < 70;
2. Meets DSM-IV criteria for BP-I or schizophrenia, pervasive developmental disorder, autism spectrum disorders, current substance dependence;
3. History of medical condition known to affect the brain;
4. current group home affiliation.

Inpatients consecutively admitted to the adolescent inpatient unit of the Zucker Hillside Hospital, NY