title: Correlation between frontal lobe oxy-hemoglobin and severity of depression assessed using near-infrared spectroscopy.
abstract: The search for objective biomarkers of psychiatric disorders has a long history. Despite this, no universally accepted instruments or methods to detect biomarkers have been developed. One potential exception is near-infrared spectroscopy, although interpreting the measures of blood flow recorded with this technique remains controversial. In this study, we aimed to investigate the relationship between recorded blood flow and depression severity assessed using the Hamilton depression scale in patients with various psychiatric disorders.
  
  
  
  Enrolled patients (n=43) had DSM-IV diagnoses of major depressive disorder (n=25), bipolar disorder I (n=5), schizophrenia (n=3), dysthymic disorder (n=3), psychotic disorder (n=3), panic disorder (n=2), and Obsessive Compulsive Disorder (n=2). The verbal fluency task was administered during blood flow recording from the frontal and temporal lobes.
  
  
  
  We found that severity of depression was negatively correlated with the integral value of blood flow in the frontal lobe, irrespective of psychiatric diagnosis (F=5.94, p=0.02).
  
  
  
  Our results support blood flow in the frontal lobe as a potential biomarker of depression severity across various psychiatric disorders.
  
  
  
  Limited sample size, no replication in the second set.
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Kawano
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan. Electronic address: psy052@osaka-med.ac.jp.
authors.forename: Tetsufumi
authors.initials: T
authors.lastname: Kanazawa
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kikuyama
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tsutsumi
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Kinoshita
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kawabata
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Yamauchi
authors.affiliation: Kansai University, Suita, Osaka, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Uenishi
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Seiya
authors.initials: S
authors.lastname: Kawashige
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Imazu
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Katsutaka
authors.initials: K
authors.lastname: Toyoda
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Nishizawa
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Mayuko
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Tatsushi
authors.initials: T
authors.lastname: Okayama
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Wakako
authors.initials: W
authors.lastname: Odo
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ide
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Soichiro
authors.initials: S
authors.lastname: Maruyama
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Tarutani
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Koh
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yoneda
mesh_terms: D000328:Adult; D015415:Biomarkers; D003866:Depressive Disorder / Q000378:metabolism / Q000523:psychology; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000502:physiology; D006439:Hemodynamics; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000378:metabolism / Q000523:psychology; D008875:Middle Aged; D009483:Neuropsychological Tests; D010108:Oxyhemoglobins / Q000378:metabolism*; D011569:Psychiatric Status Rating Scales; D012039:Regional Blood Flow / Q000502:physiology; D012720:Severity of Illness Index; D019265:Spectroscopy, Near-Infrared; D013702:Temporal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000502:physiology
chemical_list: D015415:Biomarkers; D010108:Oxyhemoglobins
keywords: Biomarker; Blood flow; Depression; Frontal lobe; NIRS; Near-infrared spectroscopy