title: Regional brain asymmetries in major depression with or without an anxiety disorder: a quantitative electroencephalographic study.
abstract: Studies of brain activity in affective disorders need to distinguish between effects of depression and anxiety because of the substantial comorbidity of these disorders. Based on a model of asymmetric hemispheric activity in depression and anxiety, it was predicted that anxious and nonanxious depressed patients would differ on electroencephalographic (EEG) measures of parietotemporal activity. Resting EEG (eyes closed and eyes open) was recorded from 44 unmedicated outpatients having a unipolar major depressive disorder (19 with and 25 without an anxiety disorder), and 26 normal controls using 30 scalp electrodes (13 homologous pairs over the two hemispheres and four midline sites). As predicted, depressed patients with an anxiety disorder differed from those without an anxiety disorder in alpha asymmetry. Nonanxious depressed patients showed an alpha asymmetry indicative of less activation over right than left posterior sites, whereas anxious depressed patients showed evidence of greater activation over right than left anterior and posterior sites. The findings are discussed in terms of a model in which specific symptom features of depression and anxiety are related to different patterns of regional brain activity.
authors.affiliation: Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, USA.
authors.forename: G E
authors.initials: GE
authors.lastname: Bruder
authors.forename: R
authors.initials: R
authors.lastname: Fong
authors.forename: C E
authors.initials: CE
authors.lastname: Tenke
authors.forename: P
authors.initials: P
authors.lastname: Leite
authors.forename: J P
authors.initials: JP
authors.lastname: Towey
authors.forename: J E
authors.initials: JE
authors.lastname: Stewart
authors.forename: P J
authors.initials: PJ
authors.lastname: McGrath
authors.forename: F M
authors.initials: FM
authors.lastname: Quitkin
mesh_terms: D000328:Adult; D000513:Alpha Rhythm; D001008:Anxiety Disorders / Q000175:diagnosis* / Q000503:physiopathology; D001931:Brain Mapping / Q000295:instrumentation; D002540:Cerebral Cortex / Q000503:physiopathology; D015897:Comorbidity; D003866:Depressive Disorder / Q000175:diagnosis* / Q000503:physiopathology; D004292:Dominance, Cerebral / Q000502:physiology*; D004569:Electroencephalography / Q000295:instrumentation*; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis / Q000503:physiopathology; D016584:Panic Disorder / Q000175:diagnosis / Q000503:physiopathology; D010698:Phobic Disorders / Q000175:diagnosis / Q000503:physiopathology; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*