A total of 22 bipolar individuals who had not participated in any of our previous neuroimaging studies were identified using DSM-IV criteria with the Structured Clinical Interview for DSM-IV (SCID-I) (37 ). All bipolar individuals were recruited from the Western Psychiatric Institute and Clinic, Mood Disorders Treatment and Research Program, University of Pittsburgh, Pittsburgh, PA, USA (47% female). Three of these were excluded from analyses due to excessive movement (>5 mm) during or inability to complete scanning procedures, allowing data of 19 bipolar individuals to be analyzed. Euthymic status was defined, a priori, as having been in remission for at least two months as assessed by SCID and clinical interview. All but one bipolar individual (who scored 11) scored <7 on the Hamilton Rating Scale for Depression 25-item version (HRSD-25) (38 (link)). This individual was included in the analyses because clinical evaluation deemed eligibility for inclusion into the study on grounds other than the rating on the HRSD-25, i.e., SCID interview. All bipolar individuals scored <10 on the Young Mania Rating Scale (39 (link)). For means, standard deviations, mean illness duration and age of illness onset, see Table 1. Eleven of these bipolar individuals had other (multiple) comorbid diagnoses, such as eating (binge eating) disorder (n = 3), substance use disorder (n = 5), specific (n = 2) or social (n = 1) phobia, panic disorder (n = 2), generalized anxiety disorder (n = 1), anxiety disorder not otherwise specified (NOS) (n = 1) and obsessive compulsive disorder (n = 1). Three bipolar individuals were symptomatic for comorbidities of specific phobia (n = 1), social phobia (n = 1), and anxiety disorder NOS (n = 1) in the past month prior to their assessment. All but one of the bipolar individuals were taking medication; one was taking mood-stabilizer monotherapy (lithium), five were taking antipsychotic monotherapy, and 12 were taking multiple medications for at least one month prior to the study. For details of medication combinations, see Table 2. Additionally recruited by advertisement were 24 healthy individuals gender ratio matched with bipolar individuals (54% female) without current and lifetime personal (SCID-I criteria) or family history of psychiatric disorder. There were no significant between-group differences in age or verbal IQ as estimated by National Adult Reading Test (NART) (40 ). For means, standard deviations and range see Table 1.
Exclusion criteria included borderline personality disorder (SCID-II criteria), history of head injury or neurological disease, non-right handedness (Annett criteria) (41 (link)) and failure to meet magnetic resonance imaging (MRI) screening criteria (pregnancy, metallic fragments, cardiac pacemaker, or claustrophobia). Additionally, patients reporting drug and alcohol dependence and abuse within the past three months (except episodic abuse related to mood episodes) were excluded. After complete description of the study to participants, written informed consent was obtained. The University of Pittsburgh Institutional Review Board approved this study.