title: Anatomical correlates of cognitive functions in early Parkinson's disease patients.
abstract: BACKGROUND
  Cognitive deficits may occur early in Parkinson's disease (PD) but the extent of cortical involvement associated with cognitive dysfunction needs additional investigations. The aim of our study is to identify the anatomical pattern of cortical thickness alterations in patients with early stage PD and its relationship with cognitive disability.
  
  
  METHODS
  We recruited 29 PD patients and 21 healthy controls. All PD patients performed an extensive neuropsychological examination and 14 were diagnosed with mild cognitive impairment (PD-MCI). Surface-based cortical thickness analysis was applied to investigate the topographical distribution of cortical and subcortical alterations in early PD compared with controls and to assess the relationship between cognition and regional cortical changes in PD-MCI.
  
  
  RESULTS
  Overall PD patients showed focal cortical (occipital-parietal areas, orbito-frontal and olfactory areas) and subcortical thinning when compared with controls. PD-MCI showed a wide spectrum of cognitive deficits and related significant regional thickening in the right parietal-frontal as well as in the left temporal-occipital areas.
  
  
  CONCLUSIONS
  Our results confirm the presence of changes in grey matter thickness at relatively early PD stage and support previous studies showing thinning and atrophy in the neocortex and subcortical regions. Relative cortical thickening in PD-MCI may instead express compensatory neuroplasticity. Brain reserve mechanisms might first modulate cognitive decline during the initial stages of PD.
authors.affiliation: Department for Parkinson's Disease, "Fondazione Ospedale San Camillo," I.R.C.C.S., Venice, Italy. roberta.biundo@ospedalesancamillo.net
authors.forename: Roberta
authors.initials: R
authors.lastname: Biundo
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Calabrese
authors.forename: Luca
authors.initials: L
authors.lastname: Weis
authors.forename: Silvia
authors.initials: S
authors.lastname: Facchini
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Ricchieri
authors.forename: Paolo
authors.initials: P
authors.lastname: Gallo
authors.forename: Angelo
authors.initials: A
authors.lastname: Antonini
mesh_terms: D000368:Aged; D001921:Brain / Q000473:pathology*; D016022:Case-Control Studies; D003071:Cognition; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000473:pathology* / Q000523:psychology*