title: [A theoretical review of category-specific impairment, its entity and the methodological problems associated with its study].
abstract: BACKGROUND
  Studies on category-specific claim to provide insights on structure and organization of semantic information. This type of phenomenon consists of the selective impairment of the information on a domain, for instance, living things (animals) but the sparing of nonliving things (tools), or vice versa. Despite the large number of studies purportedly documenting double dissociations between both domains, the lack of theoretical debate on how to empirically define such dissociations is unclear, e.g. how they should be evaluated and reported.
  
  
  METHODS
  In this work, a review of literature on category-specific and the explanatory models is showed. A critical methodological is done, on the basis of three findings: 1) lack of normal control groups in the majority of case studies; 2) the questionable utilization of double dissociations; and 3) the presence of problems due to a 'ceiling effect' in most group studies of Alzheimer disease patients.
  
  
  CONCLUSIONS
  It is claimed that while domain specificity may be a legitimate phenomenon, the critical review of literature do not provide a strong empirical foundation for the domain fractionations claimed in this literature.
authors.affiliation: School of Psychology, University of Hertfordshire, Hatfiled, Gran Bretaña.
authors.forename: K R
authors.initials: KR
authors.lastname: Laws
authors.forename: F J
authors.initials: FJ
authors.lastname: Moreno-Martínez
authors.forename: M
authors.initials: M
authors.lastname: Goñi-Imízcoz
mesh_terms: D000849:Anomia / Q000503:physiopathology*; D003072:Cognition Disorders / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008569:Memory Disorders / Q000473:pathology / Q000503:physiopathology*; D009483:Neuropsychological Tests; D021641:Recognition, Psychology; D015203:Reproducibility of Results; D012196:Review Literature as Topic; D012660:Semantics