title: Neuroanatomical abnormalities before onset of delusions in patients with Alzheimer's disease: a voxel-based morphometry study.
abstract: BACKGROUND
  Structural brain abnormalities associated with delusions in Alzheimer's disease are poorly understood. In addition, whether the neural substrate underlying the delusions develops before the onset of the delusions is unclear. In this study, we used a voxel-based morphometry approach to examine the existence of regional structural abnormalities at baseline in patients with Alzheimer's disease who did and who did not develop delusions.
  
  
  METHODS
  Using the Neuropsychiatric Inventory, we identified patients with Alzheimer's disease who exhibited delusions during a 2-year period. All the patients had undergone a magnetic resonance imaging examination at the start of the study period (baseline). We conducted a voxel-based morphometry analysis using statistical parametric mapping (SPM5) software and compared the results of patients with Alzheimer's disease who did and did not develop delusions.
  
  
  RESULTS
  Compared with the patients who did not develop delusions (n = 35), the patients who did develop delusions (n = 18) had significantly smaller gray matter volumes on both sides of the parahippocampal gyrus, the right posterior cingulate gyrus, the right orbitofrontal cortex, both sides of the inferior frontal cortex, the right anterior cingulate, and the left insula.
  
  
  CONCLUSIONS
  Structural brain abnormalities involving both the frontal and medial temporal lobes may be crucial to the expression of delusions in patients with Alzheimer's disease.
authors.affiliation: Department of Neuropsychiatry, Keio University School of Medicine, Shinjuku-ku, Tokyo.
authors.forename: Shutaro
authors.initials: S
authors.lastname: Nakaaki
authors.forename: Junko
authors.initials: J
authors.lastname: Sato
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Torii
authors.forename: Mizuki
authors.initials: M
authors.lastname: Oka
authors.forename: Atsushi
authors.initials: A
authors.lastname: Negi
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakamae
authors.forename: Jin
authors.initials: J
authors.lastname: Narumoto
authors.forename: Jun
authors.initials: J
authors.lastname: Miyata
authors.forename: Toshi A
authors.initials: TA
authors.lastname: Furukawa
authors.forename: Masaru
authors.initials: M
authors.lastname: Mimura
keywords: Alzheimer’s disease; delusions; structural brain abnormalities; voxel-based morphometry