title: Emotion regulation before and after transcranial magnetic stimulation in obsessive compulsive disorder.
abstract: BACKGROUND
  Impaired emotion regulation may underlie exaggerated emotional reactivity in patients with obsessive compulsive disorder (OCD), yet instructed emotion regulation has never been studied in the disorder.
  
  
  METHODS
  This study aimed to assess the neural correlates of emotion processing and regulation in 43 medication-free OCD patients and 38 matched healthy controls, and additionally test if these can be modulated by stimulatory (patients) and inhibitory (controls) repetitive transcranial magnetic stimulation (rTMS) over the left dorsolateral prefrontal cortex (dlPFC). Participants performed an emotion regulation task during functional magnetic resonance imaging before and after a single session of randomly assigned real or sham rTMS. Effect of group and rTMS were assessed on self-reported distress ratings and brain activity in frontal-limbic regions of interest.
  
  
  RESULTS
  Patients had higher distress ratings than controls during emotion provocation, but similar rates of distress reduction after voluntary emotion regulation. OCD patients compared with controls showed altered amygdala responsiveness during symptom provocation and diminished left dlPFC activity and frontal-amygdala connectivity during emotion regulation. Real v. sham dlPFC stimulation differentially modulated frontal-amygdala connectivity during emotion regulation in OCD patients.
  
  
  CONCLUSIONS
  We propose that the increased emotional reactivity in OCD may be due to a deficit in emotion regulation caused by a failure of cognitive control exerted by the dorsal frontal cortex. Modulatory rTMS over the left dlPFC may influence automatic emotion regulation capabilities by influencing frontal-limbic connectivity.
authors.affiliation: Department of Psychiatry,VU University Medical Center,Amsterdam,The Netherlands.
authors.forename: S J
authors.initials: SJ
authors.lastname: de Wit
authors.affiliation: Neuroscience Campus Amsterdam,The Netherlands.
authors.forename: Y D
authors.initials: YD
authors.lastname: van der Werf
authors.affiliation: Department of Clinical Neuroscience,Centre for Psychiatric Research and Education,Karolinska Institutet,Stockholm,Sweden.
authors.forename: D
authors.initials: D
authors.lastname: Mataix-Cols
authors.affiliation: Department of Psychiatry,VU University Medical Center,Amsterdam,The Netherlands.
authors.forename: J P
authors.initials: JP
authors.lastname: Trujillo
authors.affiliation: Department of Psychiatry,VU University Medical Center,Amsterdam,The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: van Oppen
authors.affiliation: Department of Psychiatry,VU University Medical Center,Amsterdam,The Netherlands.
authors.forename: D J
authors.initials: DJ
authors.lastname: Veltman
authors.affiliation: Department of Psychiatry,VU University Medical Center,Amsterdam,The Netherlands.
authors.forename: O A
authors.initials: OA
authors.lastname: van den Heuvel
mesh_terms: D000328:Adult; D000679:Amygdala / Q000503:physiopathology*; D016022:Case-Control Studies; D004644:Emotions; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D009483:Neuropsychological Tests; D009771:Obsessive-Compulsive Disorder / Q000628:therapy*; D017397:Prefrontal Cortex / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D057566:Self Report; D050781:Transcranial Magnetic Stimulation
keywords: Dorsolateral prefrontal cortex; emotion regulation; functional magnetic resonance imaging; obsessive compulsive disorder; transcranial magnetic stimulation