title: Error-related brain activity dissociates hoarding disorder from obsessive-compulsive disorder.
abstract: BACKGROUND
  Obsessive-compulsive disorder (OCD) is associated with an abnormally large error-related negativity (ERN), an electrophysiological measure of error monitoring in response to performance errors, but it is unclear if hoarding disorder (HD) also shows this abnormality. This study aimed to determine whether the neurophysiological mechanisms underlying error monitoring are similarly compromised in HD and OCD.
  
  
  METHODS
  We used a visual flanker task to assess ERN in response to performance errors in 14 individuals with HD, 27 with OCD, 10 with HD+OCD, and 45 healthy controls (HC). Age-corrected performance and ERN amplitudes were examined using analyses of variance and planned pairwise group comparisons.
  
  
  RESULTS
  A main effect of hoarding on ERN (p = 0.031) was observed, indicating ERN amplitudes were attenuated in HD relative to non-HD subjects. A group × age interaction effect on ERN was also evident. In HD-positive subjects, ERN amplitude deficits were significantly greater in younger individuals (r = -0.479, p = 0.018), whereas there were no significant ERN changes with increasing age in OCD and HC participants.
  
  
  CONCLUSIONS
  The reduced ERN in HD relative to OCD and HC provides evidence that HD is neurobiologically distinct from OCD, and suggests that deficient error monitoring may be a core pathophysiological feature of HD. This effect was particularly prominent in younger HD participants, further suggesting that deficient error monitoring manifests most strongly early in the illness course and/or in individuals with a relatively early illness onset.
authors.affiliation: Department of Psychiatry,University of California,San Francisco,CA,USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Mathews
authors.affiliation: California School of Professional Psychology (CSPP),Alliant International University.
authors.forename: V B
authors.initials: VB
authors.lastname: Perez
authors.affiliation: Department of Psychiatry,University of California,San Francisco,CA,USA.
authors.forename: B J
authors.initials: BJ
authors.lastname: Roach
authors.affiliation: Department of Psychiatry,University of California,San Francisco,CA,USA.
authors.forename: S
authors.initials: S
authors.lastname: Fekri
authors.affiliation: Department of Psychiatry,University of California,San Francisco,CA,USA.
authors.forename: O
authors.initials: O
authors.lastname: Vigil
authors.affiliation: Department of Psychiatry,University of California,San Francisco,CA,USA.
authors.forename: E
authors.initials: E
authors.lastname: Kupferman
authors.affiliation: Department of Psychiatry,University of California,San Francisco,CA,USA.
authors.forename: D H
authors.initials: DH
authors.lastname: Mathalon
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001921:Brain / Q000503:physiopathology*; D016022:Case-Control Studies; D004569:Electroencephalography; D005260:Female; D000067836:Hoarding Disorder / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000503:physiopathology*; D013647:Task Performance and Analysis; D055815:Young Adult
keywords: Electroencephalography/event-related potentials (EEG/ERP); error monitoring; error-related negativity (ERN); hoarding; neurophysiological; obsessive-compulsive disorder (OCD)