title: Impulsivity and neural correlates of response inhibition in schizophrenia.
abstract: BACKGROUND
  The clinical picture of schizophrenia is frequently worsened by manifestations of impulsivity. However, the neural correlates of impulsivity in this disorder are poorly known. Although impulsivity has been related to disturbances of the neural processes underlying response inhibition, no studies have yet examined the relationship between these processes and psychometric measures of impulsivity in schizophrenia. This was the aim of the current investigation.
  
  
  METHODS
  Event-related functional magnetic resonance imaging in conjunction with a Go/NoGo task was employed to probe the neural activity associated with response inhibition in 26 patients with schizophrenia and 30 healthy comparison subjects. All participants also completed the Barratt Impulsiveness Scale - version 11 (BIS-11). Voxel-wise regression analyses were used to examine the relationship between the BIS-11 score and brain activation during response inhibition in each group.
  
  
  RESULTS
  Patients with schizophrenia were more impulsive than healthy subjects, as indicated by higher BIS-11 scores. Patients, but not healthy subjects, were found to display a positive correlation between these scores and cerebral activation associated with response inhibition. This correlation involves a unique cluster localized within the right ventrolateral prefrontal cortex (VLPFC), a key node of the brain network subserving response inhibition.
  
  
  CONCLUSIONS
  We evidenced in patients with schizophrenia that greater BIS-11 scores are associated with greater activation within the right VLPFC during response inhibition. This finding suggests that the efficiency of this brain region to process inhibitory control is reduced in the more impulsive patients.
authors.affiliation: Institut de Neurosciences Cognitives de la Méditerranée, UMR 6193 CNRS - Université de la Méditerranée, Marseille, France. arthur.kaladjian@univmed.fr
authors.forename: A
authors.initials: A
authors.lastname: Kaladjian
authors.forename: R
authors.initials: R
authors.lastname: Jeanningros
authors.forename: J-M
authors.initials: JM
authors.lastname: Azorin
authors.forename: J-L
authors.initials: JL
authors.lastname: Anton
authors.forename: P
authors.initials: P
authors.lastname: Mazzola-Pomietto
mesh_terms: D000328:Adult; D001931:Brain Mapping; D016022:Case-Control Studies; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D007175:Impulsive Behavior; D007266:Inhibition, Psychological; D008279:Magnetic Resonance Imaging; D008297:Male; D017397:Prefrontal Cortex / Q000503:physiopathology*; D011597:Psychomotor Performance; D012044:Regression Analysis; D012559:Schizophrenia / Q000503:physiopathology*; D012565:Schizophrenic Psychology