SEMANTIC MEMORY IN NORMAL AGING AND ALZHEIMER TYPE DEMENTIA.
Item
-
Title
-
SEMANTIC MEMORY IN NORMAL AGING AND ALZHEIMER TYPE DEMENTIA.
-
Identifier
-
AAI8611365
-
identifier
-
8611365
-
Creator
-
MASUR, DAVID M.
-
Contributor
-
Jeffrey Rosen
-
Date
-
1986
-
Language
-
English
-
Publisher
-
City University of New York.
-
Subject
-
Psychology, Experimental | Gerontology
-
Abstract
-
Semantic memory is purported to be that aspect of memory specifically concerned with the representation and organization of word meanings. The present study investigated the structure of semantic memory in a group of normal elderly individuals (mean age = 81.5 years), and in a group of individuals diagnosed as having mild Alzheimer Type Dementia primarily through the administration of a timed sentence verification task. This task required subjects to decide as quickly as possible whether sentences consisting of various exemplar-category relationships were true or false. The original version of this task was introduced by McCloskey and Glucksberg (1979) and provided evidence for a model of semantic memory that is based on the processing of features in a probabilistic manner. An additional goal of the dissertation was the use of the sentence verification task to investigate changes in semantic memory in Alzheimer Type Dementia resulting from the administration of oral physostigmine, a cholinesterase inhibitor.;The results demonstrated that normal elderly subjects maintained preservation of semantic memory by producing reaction time patterns of sentence verification that were consistent with those predicted by a probabilistic semantic model. In contrast, the Alzheimer group demonstrated anomalous patterns of verification, suggestive of marked semantic disruption. However, a case by case evaluation of the subjects in the Alzheimer group revealed substantial differences in the severity of semantic disruption, despite a careful attempt to include only those subjects with mild cognitive impairment. This observation supports the notion of subgroups of Alzheimer Type Dementia having differential cognitive abilities, and suggests that there is a demonstrable pattern of decline in semantic competence within the classification of mild impairment. Finally, ingestion of oral physostigmine did not improve the overall performance of the Alzheimer group on semantic verification, but did appear to have a positive effect on the ability of these subjects to make decisions regarding certain aspects of semantic information.
-
Type
-
dissertation
-
Source
-
PQT Legacy CUNY.xlsx
-
degree
-
Ph.D.
-
Program
-
Psychology
