Emotional Dynamics and Mood Instability in Bipolar Disorder

Study start date: November 1, 2025

Inclusion Criteria 1. Age 18 to 65 years 2. Male or female 3. BMI between 18.5 and 38.0 kg/m2 at Screening 4. Capable of understanding and complying with study requirements 5. Fluent in English 6. Able to provide informed consent BD Group: 7. Meet the DSM-5 diagnostic criteria for BD-I or BD-II who are currently depressed or mixed state defined by the Mini-International Neuropsychiatric Interview (MINI) 8. Moderate or greater depressive symptom severity (MADRS ≥ 15 or PHQ-9 ≥ 10) HC Group: 9. No current or past psychiatric disorder (verified by MINI) Exclusion Criteria 1. No telephone or easy access to a telephone 2. Significant medical problems as identified by the medical screening questionnaire: e.g. a history of unstable liver or renal insufficiency; glaucoma; significant and unstable cardiac, vascular, pulmonary, gastrointestinal, endocrine, neurologic, hematologic, rheumatologic, or metabolic disturbance; or any other condition that, in the opinion of the investigator, would make participation not be in the best interest (e.g., compromise the well-being) of the participant or that could prevent, limit, or confound the protocol-specified assessments 3. A positive test for drugs of abuse, including alcohol (breath test), cocaine, opiates, amphetamines, methamphetamines, phencyclidine, benzodiazepines, barbiturates, methadone, and oxycodone 4. Drug or alcohol intoxication (based on positive UTOX or breathalyzer test at screening or study session) or reported alcohol/drug withdrawal, last cannabis use must be \>48 hours prior to study session. 5. Current DSM-5 diagnosis of a psychosis spectrum disorder or moderate to severe substance use disorder 6. Moderate to severe traumatic brain injury or other neurocognitive disorder with evidence of neurological deficits, neurological disorders, or severe or unstable medical conditions that might be compromised by participation in the study (to be determined by primary care provider) 7. Current significant suicidal ideation or suicide attempt within the past 3 months. 8. Change in the dose or prescription of a medication within the 6 weeks before enrolling in the study that could affect brain functioning, e.g., anxiolytics, antipsychotics, antidepressants, or mood stabilizers 9. Taking drugs that affect the fMRI hemodynamic response (e.g., methylphenidate, acetazolamide, excessive caffeine intake \> 1000 mg/day) 10. MRI contraindications as documented on the MR Environment Screening 11. Unwillingness or inability to complete any of the major aspects of the study protocol, including magnetic resonance imaging (i.e., due to claustrophobia), or behavioral assessment. However, failing to complete some individual aspects of these assessment sessions will be acceptable (i.e., being unwilling to answer individual items on some questionnaires or being unwilling to complete a behavioral task) 12. Non-correctable vision or hearing problems