title: The role of feature sharedness in the organization of semantic knowledge: insights from semantic dementia.
abstract: OBJECTIVE
  The present study directly evaluated the impact of feature sharedness on the differences between superordinate and basic-level concepts observed in semantic dementia (SD) patients.
  
  
  METHODS
  For this purpose, we studied a group of 6 SD patients and a group of 12 matched controls using a sentence verification task in which we orthogonally manipulated feature sharedness (more vs. less shared) and concept level (basic level vs. superordinate).
  
  
  RESULTS
  Main results showed that the superordinate advantage in SD patients was observed for more shared features but not for less shared features (p < .05, η(p)2 = .36).
  
  
  CONCLUSIONS
  These results directly support the role of feature sharedness in explaining the hierarchical organization of semantic knowledge and the specific to general pattern of knowledge deterioration in SD in particular.
authors.affiliation: Faculty of Psychology, University of Lisbon, Lisbon, Portugal. jfmarques@fp.ul.pt
authors.forename: J Frederico
authors.initials: JF
authors.lastname: Marques
authors.forename: Annik
authors.initials: A
authors.lastname: Charnallet
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D003210:Concept Formation / Q000502:physiology*; D005260:Female; D057174:Frontotemporal Lobar Degeneration / Q000503:physiopathology* / Q000523:psychology*; D006801:Humans; D019359:Knowledge; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012660:Semantics; D013702:Temporal Lobe / Q000473:pathology