title: Multichannel near-infrared spectroscopy in depression and schizophrenia: cognitive brain activation study.
abstract: BACKGROUND
  Recent developments in near-infrared spectroscopy (NIRS) have enabled the noninvasive clarification of brain functions in psychiatric disorders with measurement of hemoglobin concentrations as cerebral blood volume.
  
  
  METHODS
  Ten patients with depression, 13 patients with schizophrenia, and 16 age- and gender-matched healthy control subjects participated in the study after giving consent. The relative concentrations of oxyhemoglobin [oxyHb] were measured with frontal and temporal probes every.1 sec during word fluency and unilateral finger tapping tasks, with two 24-channel NIRS machines.
  
  
  RESULTS
  The [oxyHb] increase patterns during the word fluency task varied among the three groups, although their task performances were similar: the depression group was characterized by a smaller [oxyHb] increase during the first half of the task period and the schizophrenic group by a small trough of [oxyHb] at the start of the task period and [oxyHb] re-increase in the posttask period. [OxyHb] increases during the finger-tapping task were rather larger in the patient groups than in the control group.
  
  
  CONCLUSIONS
  The characteristic time courses of [oxyHb] changes in the frontal lobe were elucidated for depression and schizophrenia. Near-infrared spectroscopy, with its noninvasiveness and high time resolution, can be a useful tool for research and clinical purposes in psychiatry.
authors.affiliation: Department of Psychiatry and Human Behavior, Gunma University Graduate School of Medicine, Gunma, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Suto
authors.forename: Masato
authors.initials: M
authors.lastname: Fukuda
authors.forename: Makoto
authors.initials: M
authors.lastname: Ito
authors.forename: Toru
authors.initials: T
authors.lastname: Uehara
authors.forename: Masahiko
authors.initials: M
authors.lastname: Mikuni
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping / Q000295:instrumentation / Q000379:methods*; D002560:Cerebrovascular Circulation; D003071:Cognition / Q000502:physiology*; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000378:metabolism*; D005260:Female; D005625:Frontal Lobe / Q000098:blood supply / Q000378:metabolism*; D006801:Humans; D008297:Male; D016555:Matched-Pair Analysis; D008875:Middle Aged; D010108:Oxyhemoglobins / Q000378:metabolism*; D011597:Psychomotor Performance / Q000502:physiology; D012559:Schizophrenia / Q000175:diagnosis / Q000378:metabolism*; D019265:Spectroscopy, Near-Infrared; D013702:Temporal Lobe / Q000098:blood supply / Q000378:metabolism; D014705:Verbal Behavior / Q000502:physiology
chemical_list: D010108:Oxyhemoglobins