title: Neurophysiological evidence of cognitive inhibition anomalies in persons with major depressive disorder.
abstract: OBJECTIVE
  The neural correlates of inhibitory deficits for emotional semantic material in persons with major depressive disorder (MDD) were investigated.
  
  
  METHODS
  Individuals (n=15) with a diagnosis of MDD or MDD in partial remission, and healthy controls (n=14) underwent recording of event-related brain potentials (ERPs) while performing a computerized emotional Stroop task.
  
  
  RESULTS
  There were no group performance differences on the emotional Stroop task. However, the analysis of ERP waveforms revealed a larger negative wave peaking at about 170ms over the left than the right hemisphere only in controls; a negative displacement (N450) at parietal sites for positive and negative words only for persons with MDD; in both groups, processing negative and positive words was associated with a positive displacement that peaked at about 450ms and was larger over the left lateral frontal region; and, the N450 modulation correlated with negative automatic thinking and depressive symptoms.
  
  
  CONCLUSIONS
  The electrophysiological data reveal early changes in neural activity associated with word processing as well as valence-related changes in the N450 component at parietal sites in MDD.
  
  
  CONCLUSIONS
  This valence-related increase in N450 amplitude at parietal sites may reflect an automatic capture of attention by words with emotional valence.
authors.affiliation: Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, Canada. hmcneely@stjosham.on.ca
authors.forename: Heather E
authors.initials: HE
authors.lastname: McNeely
authors.forename: Mark A
authors.initials: MA
authors.lastname: Lau
authors.forename: Bruce K
authors.initials: BK
authors.lastname: Christensen
authors.forename: Claude
authors.initials: C
authors.lastname: Alain
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology; D003072:Cognition Disorders / Q000209:etiology* / Q000503:physiopathology / Q000523:psychology*; D003865:Major Depressive Disorder / Q000150:complications* / Q000503:physiopathology / Q000523:psychology*; D004569:Electroencephalography; D004644:Emotions / Q000502:physiology; D005071:Evoked Potentials; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology