Mindfulness in Mood Dysregulated Youth

Inclusion Criteria: To be included in this study, subjects must meet the following criteria: 1. Ages 10 -17 years; inclusive at the time of consent 2. At least one biological parent with bipolar I disorder, confirmed with the SCID-P/L 3. CDRS-R score \> 28 or YMRS score \> 12 or ERC score \> 36 at screening and baseline since clinically significant elevation on any of these scales suggests mood dysregulation 4. Fluent in English 5. Provision of written informed consent/assent as previously described 6. Agrees to participate in at least 75% of sessions. Exclusion Criteria: 1. Previously documented diagnosis of mental retardation or an IQ \<70 2. Any lifetime DSM-V diagnosis of bipolar disorder, schizophrenia or other psychotic disorder 3. Previous participation in a mindfulness-based treatment, including MBCT-C 4. A substance use disorder (except nicotine or caffeine) within the past 3 months 5. Judged clinically to be at risk from suicide as defined as having active suicidal ideation, intent or plan, or a serious suicide attempt within 30 days, or a baseline CDRS-R suicide score of \>3 6. Concurrent treatment with psychotropic medications that have been adjusted during the 30 days prior to screening or are anticipated during the course of study participation 7. Psychotherapy initiated within 2 month prior to screening or plan to initiate psychotherapy during study participation 8. Significant psychiatric symptoms that require hospitalization 9. Mood symptoms resulting from acute medical illness or acute intoxication or withdrawal from drugs or alcohol as determined by medical evaluation or rapid symptom resolution 10. Female patients who are either pregnant or lactating; All girls will have a urine pregnancy test prior to MR scans 11. Any contraindication to an MRI scan (e.g., metal clips, braces or claustrophobia) 12. Neurological disorders (e.g. epilepsy) or severe head trauma resulting in loss of consciousness for \> 10 minutes or any unstable medical illness.