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

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