Memory difficulties are a prominent feature of normal human aging, and especially of Dementia of the Alzheimer's Type (DAT). There is, however, evidence that one type of memory, semantic memory, may be relatively unaffected by normal aging. Semantic memory consists of knowledge of semantic concepts and verbal symbols, and the rules for their usage. While some studies have reported semantic memory deficits in DAT, the tasks used made heavy demands on attentional capacity, and thus, may not accurately reflect the state of semantic memory structure and function in demented persons. The studies in the present application will examine similarities and differences in the semantic memory abilities of normal young, normal elderly and demented elderly persons. The tasks will employ the theoretical constructs and methodology of cognitive psychology and are designed to involve """"""""automatic"""""""" processes that make minimal demands upon attentional capacity (e.g., semantic priming tasks). Information gained in these studies should help characterize the effects that dementia and normal aging have on various aspects of semantic memory. Any differences in the effect of normal and abnormal (i.e., Alzheimer's disease) aging on semantic memory would be helpful in differential diagnosis. If, however, semantic memory is resistant to the general cognitive deterioration seen in DAT, then in the future, measurements of semantic memory performance could serve as a useful indicator of premorbid cognitive abilities, as well as a benchmark against which to evaluate cognitive decline or improvement (e.g., with pharmacological treatment) over time.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
5R01AG004791-02
Application #
3115352
Study Section
Human Development and Aging Subcommittee 1 (HUD)
Project Start
1984-04-01
Project End
1987-03-31
Budget Start
1985-04-01
Budget End
1986-03-31
Support Year
2
Fiscal Year
1985
Total Cost
Indirect Cost
Name
University of Pittsburgh
Department
Type
Schools of Medicine
DUNS #
053785812
City
Pittsburgh
State
PA
Country
United States
Zip Code
15213
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Nebes, R D; Halligan, E M (1995) Contextual constraint facilitates semantic decisions about object pictures by Alzheimer patients. Psychol Aging 10:590-6
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Nebes, R D; Brady, C B (1992) Generalized cognitive slowing and severity of dementia in Alzheimer's disease: implications for the interpretation of response-time data. J Clin Exp Neuropsychol 14:317-26
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Nebes, R D; Brady, C B (1991) The effect of contextual constraint on semantic judgments by Alzheimer patients. Cortex 27:237-46
Nebes, R D; Brady, C B (1990) Preserved organization of semantic attributes in Alzheimer's disease. Psychol Aging 5:574-9
Nebes, R D (1989) Semantic memory in Alzheimer's disease. Psychol Bull 106:377-94

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