Article

Naming and Knowing in Dementia of Alzheimer's Type

University Neurology Unit, University of Cambridge, Cambridge, United Kingdom.
Brain and Language (Impact Factor: 3.31). 09/1996; 54(2):302-25. DOI: 10.1006/brln.1996.0077
Source: PubMed

ABSTRACT We studied the relationship between naming and the integrity of physical and associative knowledge in a group of patients with dementia of the Alzheimer type (DAT) and matched normal controls. All subjects named 48 line drawings and later generated verbal definitions in response to the names of a subset of the 48 items, which included a minimum of six definitions for correctly named objects and six definitions for items that the subject failed to name. A comprehensive scoring system was designed for the definitions, including physical and associative features of a general and a specific type, a superordinate label, the core concept, and various categories of errors. The definitions generated by the DAT patients, even those in the minimal group, contained significantly less correct information than those of normal subjects, and definitions corresponding to unnamed items were more impoverished than those for named items. Particularly striking was the loss of core concept for unnamed items. There was also a disproportionate reduction in physical information on unnamed compared to named items. We conclude that quantitative assessment of verbal definitions is a sensitive index of semantic memory breakdown. Our findings offer some support for the hypothesis that successful naming depends upon integrity of the subset of semantic knowledge comprising physical features.

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    • "Pour Hodges et al. (1991), la production fréquente d'hyperonymes et de cohyponymes s'expliquerait par la dégradation des informations sémantiques spécifiques tandis que les circonlocutions montreraient que les connaissances sémantiques disponibles ne sont pas suffissantes pour permettre la production de la cible. Dans cette hypothèse, les troubles de la dénomination seraient associés à des troubles sémantiques et des troubles de la compréhension lexicale (Martin & Fedio, 1983 ; Hodges et al., 1996). De nombreux auteurs parlent ainsi de troubles lexico-sémantiques, considérés comme caractéristiques de la maladie d'Alzheimer (Huff et al., 1988, Cardebat et al. 1995 ; Joannette et al., 2006). "
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    • "to 60 ( total correct TAS scores ) . Semantic category fluency task : This simple task involves specifying as many words as possible belonging to a given category such as ' animals ' , during a period of 1 min . The dependent variable Author ' s personal copy is the number of relevant non - repeated words uttered by the subject . Various authors ( Hodges et al . , 1996 ) consider this to be one of the most reliable tasks for discriminating between the initial phases of cognitive impairment . WM evaluation task ( Yuill et al . , 1989 ) : This task measures the extent of WM through the presentation of cards consisting of three numbers . The subject is required to read the numbers of each card aloud and "
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