Semantic memory, or general knowledge about objects and events in the world, appears to be severely affected in most patients with Alzheimer's Disease (AD). The goal of the proposed research is a deeper understanding of semantic processing in AD. In overview, the following issues concerning semantic memory will be addressed. First of all, is semantic memory impaired, or does the appearance of impairment come from an attentional impairment? Second, are certain types of semantics knowledge more vulnerable to AD, and if so, why? Third, can an impairment of semantic memory account for other problems that seem, on the face things, not semantic but perceptual or lexical? Fourth, what is the relation between semantic impairments and visual impairments in the confrontation naming difficulties of AD patients? Finally, what is the status of the visual-semantic process of mental imagery in AD? The methods to be used include empirical studies of patients with AD and normal subjects, and computer simulation. We have drawn on the theoretical framework of cognitive psychology in designing studies of semantic memory, vision, and mental imagery in AD. In addition, concepts from parallel distributed processing (PDP) have guided the formulation of hypotheses concerning semantic memory in AD, and PDP computer simulations will provide tests of the computational adequacy of these hypotheses. In addition, new predictions of the computational hypotheses have been derived and will form the basis of further empirical tests with human subjects.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
1R01AG014082-01
Application #
2002014
Study Section
Human Development and Aging Subcommittee 3 (HUD)
Project Start
1997-09-30
Project End
2002-08-31
Budget Start
1997-09-30
Budget End
1998-08-31
Support Year
1
Fiscal Year
1997
Total Cost
Indirect Cost
Name
University of Pennsylvania
Department
Psychiatry
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Tippett, Lynette J; Meier, Sandra L; Blackwood, Kirsty et al. (2007) Category specific deficits in Alzheimer's disease: fact or artefact? Cortex 43:907-20
Gillihan, Seth J; Kessler, Jennifer; Farah, Martha J (2007) Memories affect mood: evidence from covert experimental assignment to positive, neutral, and negative memory recall. Acta Psychol (Amst) 125:144-54
Gillihan, Seth J; Farah, Martha J (2005) Is self special? A critical review of evidence from experimental psychology and cognitive neuroscience. Psychol Bull 131:76-97
Fellows, Lesley K; Farah, Martha J (2005) Dissociable elements of human foresight: a role for the ventromedial frontal lobes in framing the future, but not in discounting future rewards. Neuropsychologia 43:1214-21
Tippett, Lynette J; Gendall, Angela; Farah, Martha J et al. (2004) Selection ability in Alzheimer's disease: investigation of a component of semantic processing. Neuropsychology 18:163-73
Addis, Donna Rose; Tippett, Lynette J (2004) Memory of myself: autobiographical memory and identity in Alzheimer's disease. Memory 12:56-74
Fellows, Lesley K; Farah, Martha J (2003) Ventromedial frontal cortex mediates affective shifting in humans: evidence from a reversal learning paradigm. Brain 126:1830-7
Wilson, Kevin D; Farah, Martha J (2003) When does the visual system use viewpoint-invariant representations during recognition? Brain Res Cogn Brain Res 16:399-415
Tippett, Lynette J; Blackwood, Kirsty; Farah, Martha J (2003) Visual object and face processing in mild-to-moderate Alzheimer's disease: from segmentation to imagination. Neuropsychologia 41:453-68
Thompson-Schill, S L; Aguirre, G K; D'Esposito, M et al. (1999) A neural basis for category and modality specificity of semantic knowledge. Neuropsychologia 37:671-6

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