title: Different neural pathways to negative affect in youth with pediatric bipolar disorder and severe mood dysregulation.
abstract: Questions persist regarding the presentation of bipolar disorder (BD) in youth and the nosological significance of irritability. Of particular interest is whether severe mood dysregulation (SMD), characterized by severe non-episodic irritability, hyper-arousal, and hyper-reactivity to negative emotional stimuli, is a developmental presentation of pediatric BD and, therefore, whether the two conditions are pathophysiologically similar. We administered the affective Posner paradigm, an attentional task with a condition involving blocked goal attainment via rigged feedback. The sample included 60 youth (20 BD, 20 SMD, and 20 controls) ages 8-17. Magnetoencephalography (MEG) examined neuronal activity (4-50 Hz) following negative versus positive feedback. We also examined reaction time (RT), response accuracy, and self-reported affect. Both BD and SMD youth reported being less happy than controls during the rigged condition. Also, SMD youth reported greater arousal following negative feedback than both BD and controls, and they responded to negative feedback with significantly greater activation of the anterior cingulate cortex (ACC) and medial frontal gyrus (MFG) than controls. Compared to SMD and controls, BD youth displayed greater superior frontal gyrus (SFG) activation and decreased insula activation following negative feedback. Data suggest a greater negative affective response to blocked goal attainment in SMD versus BD and control youth. This occurs in tandem with hyperactivation of medial frontal regions in SMD youth, while BD youth show dysfunction in the SFG and insula. Data add to a growing empirical base that differentiates pediatric BD and SMD and begin to elucidate potential neural mechanisms of irritability.
authors.affiliation: Department of Psychology, The Catholic University of America, NE, Washington, DC, USA. richb@cua.edu
authors.forename: Brendan A
authors.initials: BA
authors.lastname: Rich
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Carver
authors.forename: Tom
authors.initials: T
authors.lastname: Holroyd
authors.forename: Heather R
authors.initials: HR
authors.lastname: Rosen
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Mendoza
authors.forename: Brian R
authors.initials: BR
authors.lastname: Cornwell
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Fox
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Pine
authors.forename: Richard
authors.initials: R
authors.lastname: Coppola
authors.forename: Ellen
authors.initials: E
authors.lastname: Leibenluft
mesh_terms: D000293:Adolescent; D000339:Affect; D001714:Bipolar Disorder / Q000503:physiopathology* / Q000523:psychology*; D001931:Brain Mapping / Q000379:methods; D002648:Child; D030141:Feedback, Psychological; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006179:Gyrus Cinguli / Q000503:physiopathology; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D009434:Neural Pathways / Q000503:physiopathology*; D009483:Neuropsychological Tests; D011930:Reaction Time; D012720:Severity of Illness Index