title: Prefrontal cortex activation is associated with a discrepancy between self- and observer-rated depression severities of major depressive disorder: a multichannel near-infrared spectroscopy study.
abstract: BACKGROUND
  Studies on major depressive disorder (MDD) show that the degree of correlation between the Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HAMD) varies widely. We aimed to determine whether this discrepancy reflects specific functional abnormalities in the frontotemporal cortex.
  
  
  METHODS
  Mildly depressed or euthymic patients with MDD (n=52), including 21 patients with MDD with the discrepancy, i.e., those with low HAMD17 scores (≤13) but high BDI-II scores (>28), and 31 patients without the discrepancy, i.e., those with low HAMD17 scores and low BDI-II scores (≤28), participated in the study along with 48 control subjects. Regional changes of oxygenated hemoglobin (oxy-Hb) levels during a verbal fluency task (VFT) were monitored using a 52-channel near-infrared spectroscopy (NIRS) device.
  
  
  RESULTS
  In the frontotemporal regions, mean oxy-Hb changes induced by the VFT were significantly smaller in patients with MDD than in control subjects. In 5 channels within frontal regions, the increase in mean oxy-Hb levels was significantly greater in MDD patients with the BDI-HAMD discrepancy than in those without the discrepancy. In 6 channels within the frontal region of the patients with MDD, significant positive correlations were observed between mean oxy-Hb changes and BDI total scores (ρ=0.38-0.59; P<0.05, false discovery rate corrected).
  
  
  CONCLUSIONS
  Our findings required replication in severely depressed patients, particularly those with melancholia.
  
  
  CONCLUSIONS
  The distinct pattern of activation of the prefrontal cortex suggests that MDD with the BDI-HAMD discrepancy is pathophysiologically different from MDD without the discrepancy.
authors.affiliation: Department of Neuropsychiatry, Kinki University Faculty of Medicine, 377-2 Ohnohigashi, Osakasayama, Osaka 589-8511, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Akashi
authors.affiliation: Department of Neuropsychiatry, Kinki University Faculty of Medicine, 377-2 Ohnohigashi, Osakasayama, Osaka 589-8511, Japan. Electronic address: tujiinoa@med.kindai.ac.jp.
authors.forename: Noa
authors.initials: N
authors.lastname: Tsujii
authors.affiliation: Department of Neuropsychiatry, Kinki University Faculty of Medicine, 377-2 Ohnohigashi, Osakasayama, Osaka 589-8511, Japan.
authors.forename: Wakako
authors.initials: W
authors.lastname: Mikawa
authors.affiliation: Department of Neuropsychiatry, Kinki University Faculty of Medicine, 377-2 Ohnohigashi, Osakasayama, Osaka 589-8511, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Adachi
authors.affiliation: Department of Neuropsychiatry, Kinki University Faculty of Medicine, 377-2 Ohnohigashi, Osakasayama, Osaka 589-8511, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Kirime
authors.affiliation: Department of Neuropsychiatry, Kinki University Faculty of Medicine, 377-2 Ohnohigashi, Osakasayama, Osaka 589-8511, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Shirakawa
mesh_terms: D000328:Adult; D003863:Depression / Q000503:physiopathology; D003866:Depressive Disorder / Q000503:physiopathology; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000378:metabolism / Q000503:physiopathology*; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010108:Oxyhemoglobins / Q000378:metabolism*; D017397:Prefrontal Cortex / Q000378:metabolism / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D012107:Research Design; D012720:Severity of Illness Index; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation
chemical_list: D010108:Oxyhemoglobins
keywords: Beck Depression Inventory; Hamilton Depression Rating Scale; Major depressive disorder; Near-infrared spectroscopy; Observer rating; Self-rating