title: Abnormal hemodynamics in schizophrenia during an auditory oddball task.
abstract: BACKGROUND
  Schizophrenia is a heterogeneous disorder characterized by diffuse brain abnormalities that affect many facets of cognitive function. One replicated finding in schizophrenia is abnormalities in the neural systems associated with processing salient stimuli in the context of oddball tasks. This deficit in the processing of salience stimuli might be related to abnormalities in orienting, attention, and memory processes.
  
  
  METHODS
  Behavioral responses and functional magnetic resonance imaging data were collected while 18 patients with schizophrenia and 18 matched healthy control subjects performed a three-stimulus auditory oddball task.
  
  
  RESULTS
  Target detection by healthy participants was associated with significant activation in all 38 regions of interest embracing distributed cortical and subcortical systems. Similar reproducibility was observed in healthy participants for processing novel stimuli. Schizophrenia patients, relative to control subjects, showed diffuse cortical and subcortical hypofunctioning during target detection and novelty processing, including bilateral frontal, temporal, and parietal cortices and amygdala, thalamus, and cerebellum.
  
  
  CONCLUSIONS
  These data replicate and extend imaging studies of target detection in schizophrenia and present new insights regarding novelty processing in the disorder. The results are consistent with the hypothesis that schizophrenia is characterized by a widespread pathologic process affecting many cerebral areas, including cortical, subcortical, and cerebellar circuits.
authors.affiliation: Clinical Cognitive Neuroscience Laboratory, Olin Neuropsychiatry Research Center, The Institute of Living, Hartford, Connecticut 06106, USA. kent.kiehl@yale.edu
authors.forename: Kent A
authors.initials: KA
authors.lastname: Kiehl
authors.forename: Michael C
authors.initials: MC
authors.lastname: Stevens
authors.forename: Kim
authors.initials: K
authors.lastname: Celone
authors.forename: Matthew
authors.initials: M
authors.lastname: Kurtz
authors.forename: John H
authors.initials: JH
authors.lastname: Krystal
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D001931:Brain Mapping; D016022:Case-Control Studies; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D010100:Oxygen / Q000097:blood; D012559:Schizophrenia / Q000503:physiopathology*
chemical_list: D010100:Oxygen