title: Pattern of semantic memory impairment in dementia of Alzheimer's type.
abstract: The specific pattern of semantic memory impairment in patients with dementia of Alzheimer's type (DAT) remains unclear. Specifically, the presence of a category-specific deficit for biological concepts (reflected in anomia for these concepts) has been questioned. We studied 9 DAT patients using a semantic association judgement test in which they had to decide which of the two given words was most like a target word (e.g., lamb: goat, sheep). The 150 target words were drawn from 6 categories: animals, clothing and furniture, fruits and vegetables, tools, action verbs, and abstract nouns. Age- and education-matched control subjects performed equivalently (between 86 and 90% correct) in all categories. Compared to control subjects, DAT patients made significantly more errors in abstract and biological nouns, but not in verbs and man-made artifacts. This pattern of semantic memory impairment--a sparing of verbs and a selective deficit of nouns in the biological category--has been documented in patients with temporal lobe damage, suggesting a critical dysfunction in the temporal lobes of DAT.
authors.affiliation: Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montréal, Canada.
authors.forename: T D
authors.initials: TD
authors.lastname: Fung
authors.forename: H
authors.initials: H
authors.lastname: Chertkow
authors.forename: F D
authors.initials: FD
authors.lastname: Templeman
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis* / Q000209:etiology*; D009483:Neuropsychological Tests; D012660:Semantics; D012720:Severity of Illness Index