Examining the Effect of EEG-guided Theta Burst Stimulation in Bipolar Disorder

Bipolar Disorder (BD) is a common and highly debilitating psychiatric disorder, however, the predisposing brain mechanisms are poorly understood. Here, the investigators will conduct a proof of concept study that will examine the effect of electroencephalography (EEG)-guided theta burst stimulation (TBS) on reducing mania/hypomania-related affect and reward driven behavior in adults with BD. The investigators hypothesize that TBS will reduce mania/hypomania-related affect and reward driven behavior in adults with BD.

This study aims to examine the effect of electroencephalography (EEG)-guided theta burst stimulation (TBS) on reducing mania/hypomania-related affect and reward driven behavior in adults with BD. Eligible participants will undergo 6 study visits: a screening visit, a baseline MRI visit, TBS motor thresholding visit, and 3 cTBS/EEG visits. Participants will receive brain stimulation and have brain activity recorded by EEG at each of the 3 cTBS/EEG study visits. The research associates (except for the research associate administering the TBS) and participants will be blinded to the brain area receiving TBS, which will be randomized and counterbalanced beforehand. Certain information is withheld to protect the scientific integrity of the study design.

The goal of the study is to reduce overactivity in the reward neural network (RNet) and increase activity in the central executive control network (CEN) using theta burst stimulation (TBS). The region in the RNet to be targeted by inhibitory (continuous, cTBS) is the left ventrolateral prefrontal cortex (vlPFC); and the region in the CEN to be targeted by excitatory (intermittent, iTBS) is the right dorsolateral prefrontal cortex (dlPFC)

Eligibility Criteria:
Inclusion criteria:

* 18-35 years of age
* Diagnosis of BD (DSM-5 criteria) in remission (euthymic for \>2 months) or in a manic/hypomanic episode \[manic/hypomanic or euthymic adults with BD (3-fifths manic/hypomanic); euthymic for \> 2 months from most recent BD episode OR current manic/hypomanic episode\]
* Not psychotic
* Score \<3 on delusions, hallucinations, unusual thought content, and conceptual disorganization items of the Positive and Negative Syndrome Scale (PANSS)
* Unmedicated or on any combination of anxiolytics (benzodiazepines, buspirone, pregabalin, hydroxyzine) as needed, and/or atypical antipsychotics, and/or lithium, and/or other mood stabilizers, and/or non-SNRI antidepressants and/or non benzodiazepine hypnotics, as these are commonly-prescribed medications for BD
* Provides the contact information of a medical provider (including but not limited to a PCP) that we may communicate with for any concerns of escalating symptoms of mania

Exclusion criteria:

* Not 18-35 years of age
* Diagnosis of BD in a depressive episode or Diagnosis of BP in partial remission, euthymia that fails to meet full remission criterion of a period of at least 2 months in which there are no significant symptoms, e.g., only partial remission of symptoms or full remission of symptoms but for \<2 months
* Diagnosis of BD in a depressive episode
* Personal and family history of epilepsy (TBS exclusion)
* Binge alcohol drinking
* Taking substances in the last month that can elevate seizure risk including but not limited to SNRI antidepressants, bupropion and stimulants (TBS exclusion)
* History of head injury, neurological, pervasive developmental disorder (e.g. autism), systemic medical disease and treatment (medical records, participant report)
* Mini-Mental State Examination score (cognitive state) \<24
* Premorbid NAART IQ estimate\<85
* Visual disturbance: \<20/40 Snellen visual acuity
* History of alcohol/substance use disorder (SUD; all substances, except nicotine), and/or illicit substance use (except cannabis) over the last 6 months (SCID-5). Note: lifetime/present cannabis use (at non-abuse (\<3 times in the past month) and non SUD levels) will be allowed, given its common usage in BD and young adults. Cannabis SUD over the last 6 months will not be allowed. Urine tests on scan days will exclude current illicit substance use (except cannabis). Salivary alcohol tests on scan days will exclude intoxicated individuals
* Binge drinking in the week before, and/or \>3 units/day for the 3 days before, and/or alcohol in the last 12 hrs before, any TBS visit, confirmed at screening and scan days (to avoid TBS during alcohol withdrawal). Alcohol/nicotine/ caffeine/cannabis use (below SCID-5 SUD, binge levels) will be allowed, and used as covariates
* MRI exclusion: metallic objects, e.g., surgical implants; claustrophobia; positive pregnancy test for females (at the MRRC) or self-report pregnancy \*Unable to understand English
* Scoring greater than or equal to 8 on HRSD at screen visit and depressive episode is confirmed on SCID-5
* Scoring greater than or equal to 18 on HRSD at any study visit
* Psychosis
* Using psychotropic medications other than those allowed in inclusion criteria
* Scoring greater than or equal to 38 on the YMRS at any study visit
* Does not provide the contact information of a medical provider (including but not limited to a PCP) that we may communicate with for any concerns of escalating symptoms of mania