title: 1910s' brains revisited. Cortical complexity in early 20th century patients with intellectual disability or with dementia praecox.
abstract: OBJECTIVE
  The idea of cortical surface anomalies in subjects with intellectual disability (mental retardation) and schizophrenia can be traced back to early 20th century qualitative observations. Since it is unknown whether modern quantitative measures of cortical complexity and folding would retrieve those early empirical observations, we measured fractal dimension and sulcal span index in photographs of human brains taken in the 1910's.
  
  
  METHODS
  Brain photographs were compared between 36 patients with mental retardation and 21 patients with dementia praecox for the fractal dimension and sulcal span index. Also, a mental retardation subgroup with no-or-non-understandable speech (n = 12) was compared with a subgroup with comprehensible speech (n = 23).
  
  
  RESULTS
  Mental retardation group had a lower whole-brain fractal dimension than dementia praecox, and a higher sulcal span index in left posterior cortex. The mental retardation subgroup with comprehensible speech had a lower fractal dimension in left hemisphere than the subgroup with no-or-non-understandable speech and a lower sulcal index in left posterior cortex.
  
  
  CONCLUSIONS
  Measures of cortical complexity and folding suggest differences between mental retardation and dementia praecox, and regional variations according to language abilities in mental retardation. The findings provide a unique picture of cortical surface changes in their original untreated form, one century ago.
authors.affiliation: Research Unit 1000, Frédéric Joliot Hospital Department, INSERM -CEA - Paris Sud University, Orsay, France.
authors.forename: A-L
authors.initials: AL
authors.lastname: Sandu
authors.forename: M-L
authors.initials: ML
authors.lastname: Paillère Martinot
authors.forename: E
authors.initials: E
authors.lastname: Artiges
authors.forename: J-L
authors.initials: JL
authors.lastname: Martinot
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000473:pathology*; D015897:Comorbidity; D005260:Female; D049673:History, 20th Century; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008607:Intellectual Disability / Q000453:epidemiology / Q000266:history / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010781:Photography; D012559:Schizophrenia / Q000266:history / Q000473:pathology*; D013064:Speech Disorders / Q000453:epidemiology / Q000266:history / Q000473:pathology*; D055815:Young Adult
keywords: cortical complexity; mental retardation; pervasive developmental disorders; schizophrenia; sulcal span index