title: Association between severe dorsolateral prefrontal dysfunction during random number generation and earlier onset in schizophrenia.
abstract: OBJECTIVE
  Schizophrenia involves impairment in attention, working memory and executive processes associated with prefrontal cortical function, an essential contributor of social functioning. Age at onset is a major factor for predicting social outcome in schizophrenia. In clinical settings, we need an objective assessment tool for evaluating prefrontal function and social outcome.
  
  
  METHODS
  Participants included 22 right-handed patients with schizophrenia and 40 gender- and age-matched healthy controls. We used a 52-channel near-infrared spectroscopy (NIRS) instrument to measure oxygenated haemoglobin ([oxy-Hb]) changes over the prefrontal cortex during a random number generation (RNG) task.
  
  
  RESULTS
  In healthy controls, we found significant [oxy-Hb] increase in the bilateral dorsolateral (DLPFC; BA9 and BA46) and ventrolateral prefrontal cortex (VLPFC; BA44, 45 and 47). The patients with schizophrenia showed significantly smaller activation than the healthy controls in the same approximate regions. In the patient group, a smaller [oxy-Hb] increase in the right DLPFC region (BA9) was significantly correlated with earlier age at onset.
  
  
  CONCLUSIONS
  NIRS can detect prefrontal cortical dysfunction associated with an executive task, which was coupled with earlier age at onset in schizophrenia.
  
  
  CONCLUSIONS
  Multichannel NIRS, a non-invasive and user-friendly instrument, may be useful in evaluating cognitive function and social outcome in clinical settings in psychiatry.
authors.affiliation: Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. skoike-tky@umin.ac.jp
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Koike
authors.forename: Ryu
authors.initials: R
authors.lastname: Takizawa
authors.forename: Yukika
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Kohei
authors.initials: K
authors.lastname: Marumo
authors.forename: Masaru
authors.initials: M
authors.lastname: Kinou
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kawakubo
authors.forename: Mark A
authors.initials: MA
authors.lastname: Rogers
authors.forename: Kiyoto
authors.initials: K
authors.lastname: Kasai
mesh_terms: D000328:Adult; D001931:Brain Mapping; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000209:etiology* / Q000473:pathology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D009483:Neuropsychological Tests; D010108:Oxyhemoglobins / Q000378:metabolism; D017397:Prefrontal Cortex / Q000378:metabolism / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D011930:Reaction Time / Q000502:physiology; D012559:Schizophrenia / Q000150:complications*; D012720:Severity of Illness Index; D019265:Spectroscopy, Near-Infrared / Q000379:methods; D055815:Young Adult
chemical_list: D010108:Oxyhemoglobins