title: Paracingulate sulcus morphology and fMRI activation detection in schizophrenia patients.
abstract: OBJECTIVE
  Altered anterior cingulate cortex activity has been consistently detected by functional imaging in schizophrenia patients. In the present study, we hypothesized that the detection of such local hypoactivity varies when the subjects' local gyrification is monitored. Using a group-statistical approach, we investigated whether the presence or absence of a paracingulate sulcus (PCS) does influence the detection of the activation patterns in the cognitive division of the anterior cingulate cortex (ACcd).
  
  
  METHODS
  fMRI data were acquired using an event-related paradigm during a task involving both priming and interference between stimuli. In the fMRI dataset collected from 13 schizophrenia patients and 16 healthy subjects, subgroups were defined according to the presence or absence of a PCS. Regional activations during interference between stimuli were examined in the ACcd of each hemisphere, using for each region of interest both voxel-based random-effects and non-parametric analyses.
  
  
  RESULTS
  ACcd activation was left-sided in healthy subjects with a PCS, and right-sided in healthy subjects devoid of a PCS. ACcd activations were detected bilaterally in schizophrenia patients with a PCS, whereas left ACcd was deactivated in patients without a PCS. Subgroup comparisons revealed no difference between healthy subjects with a PCS and patients with a PCS, whereas in the subgroups devoid of PCS, the patients exhibited a bilateral ACcd hypoactivation relative to healthy subjects.
  
  
  CONCLUSIONS
  PCS presence or absence influences the detection of ACcd activations in group-analysis of schizophrenia patients.
authors.affiliation: INSERM-CEA Research Unit URM 02-05 Neuroimaging in Psychiatry, National Institute for Health and Medical Research (INSERM) and Atomic Energy Commission (CEA), IFR49, Frédéric Joliot hospital department, Orsay, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Artiges
authors.forename: Catherine
authors.initials: C
authors.lastname: Martelli
authors.forename: Lionel
authors.initials: L
authors.lastname: Naccache
authors.forename: David
authors.initials: D
authors.lastname: Bartrés-Faz
authors.forename: Jean-Bernard
authors.initials: JB
authors.lastname: Leprovost
authors.forename: Armelle
authors.initials: A
authors.lastname: Viard
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Paillère-Martinot
authors.forename: Stanislas
authors.initials: S
authors.lastname: Dehaene
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Martinot
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D001931:Brain Mapping; D003071:Cognition / Q000502:physiology; D003220:Conflict, Psychological; D004193:Discrimination Learning / Q000502:physiology; D004292:Dominance, Cerebral / Q000502:physiology; D006179:Gyrus Cinguli / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology; D010470:Perceptual Masking / Q000502:physiology; D011340:Problem Solving / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D012016:Reference Values; D012559:Schizophrenia / Q000175:diagnosis* / Q000503:physiopathology; D012565:Schizophrenic Psychology; D018709:Statistics, Nonparametric; D013360:Subliminal Stimulation