title: White matter integrity and lack of insight in schizophrenia and schizoaffective disorder.
abstract: OBJECTIVE
  Poor insight into illness is commonly associated with schizophrenia and has implications for the clinical outcome of the disease. A better understanding of the neurobiology of these insight deficits may help the development of new treatments targeting insight. Despite the importance of this issue, the neural correlates of insight deficits in schizophrenia remain poorly understood.
  
  
  METHODS
  Thirty-six individuals diagnosed with schizophrenia or schizoaffective disorder underwent diffusion tensor imaging (DTI). The subjects were assessed on two dimensions of insight (symptom awareness and attribution of symptoms) using the Scale to Assess Unawareness of Mental Disorder (SUMD). Level of psychosis was assessed with the Positive and Negative Syndrome Scale (PANSS).
  
  
  RESULTS
  White matter abnormalities in the right superior frontal gyrus, left middle frontal gyrus, bilateral parahippocampal gyrus, adjacent to the right caudate head, right thalamus, left insula, left lentiform nucleus, left fusiform gyrus, bilateral posterior cingulate, left anterior cingulate, right cingulate gyrus, left lingual gyrus, and bilateral claustrum were associated with symptom unawareness. Misattribution of symptoms was related to deficits in the white matter adjacent to the right lentiform nucleus, left middle temporal gyrus, and the right precuneus.
  
  
  CONCLUSIONS
  Impaired insight in schizophrenia implicates a complex neural circuitry: white matter deficits in fronto-temporo brain regions are linked to symptom unawareness; compromised temporal and parietal white matter regions are involved in the misattribution of symptoms. These findings suggest the multidimensional construct of insight has multiple neural determinants.
authors.affiliation: Department of Psychiatry, New York University School of Medicine, New York, NY 10016, USA. daniel.antonius@nyumc.org
authors.forename: Daniel
authors.initials: D
authors.lastname: Antonius
authors.forename: Vasthie
authors.initials: V
authors.lastname: Prudent
authors.forename: Yasmina
authors.initials: Y
authors.lastname: Rebani
authors.forename: Debra
authors.initials: D
authors.lastname: D'Angelo
authors.forename: Babak A
authors.initials: BA
authors.lastname: Ardekani
authors.forename: Dolores
authors.initials: D
authors.lastname: Malaspina
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Hoptman
mesh_terms: D000328:Adult; D016880:Anisotropy; D001364:Awareness; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D056324:Diffusion Tensor Imaging / Q000379:methods; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D009415:Nerve Net / Q000473:pathology; D009434:Neural Pathways / Q000473:pathology; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000473:pathology* / Q000523:psychology*; D012559:Schizophrenia / Q000473:pathology*; D012565:Schizophrenic Psychology