In April 2016 Manchester eScholar was replaced by the University of Manchester’s new Research Information Management System, Pure. In the autumn the University’s research outputs will be available to search and browse via a new Research Portal. Until then the University’s full publication record can be accessed via a temporary portal and the old eScholar content is available to search and browse via this archive.

Related resources

Full-text held externally

University researcher(s)

Unpicking the semantic impairment in Alzheimer's disease: qualitative changes with disease severity.

Corbett, Faye; Jefferies, Elizabeth; Burns, Alistair; Ralph, Matthew A Lambon

Behavioural neurology. 2012;25(1):23-34.

Access to files

Full-text and supplementary files are not available from Manchester eScholar. Full-text is available externally using the following links:

Full-text held externally

Abstract

Despite a vast literature examining semantic impairment in Alzheimer's disease (AD), consensus regarding the nature of the deficit remains elusive. We re-considered this issue in the context of a framework that assumes semantic cognition can break down in two ways: (1) core semantic representations can degrade or (2) cognitive control mechanisms can become impaired. We hypothesised and confirmed that the nature of semantic impairment in AD changes with disease severity. Patients at mild or severe stages of the disorder exhibited impairment across various semantic tasks but the nature of those deficits differed qualitatively for the two groups. Commensurate with early dysfunction of the cognitive control, temporoparietal-frontal-cingulate network, characteristics of deregulated semantic cognition were exhibited by the mild AD cases. In contrast, the severe AD group reproduced features of additional degradation of core semantic representations. These results suggest that spread of pathology into lateral anterior temporal lobes in later stage AD produces degradation of semantic representations, exacerbating the already deregulated system. Moreover, the dual nature of severe patients' impairment was highlighted by disproportionately poor performance on tasks placing high demand on both conceptual knowledge and control processes--e.g., category fluency.

Bibliographic metadata

Type of resource:
Content type:
Publication type:
Published date:
Journal title:
Abbreviated journal title:
ISSN:
Place of publication:
Netherlands
Volume:
25
Issue:
1
Pagination:
23-34
Digital Object Identifier:
10.3233/BEN-2012-0346
Pubmed Identifier:
22207420
Pii Identifier:
962TL159847548V5
Access state:
Active

Institutional metadata

University researcher(s):
Academic department(s):

Record metadata

Manchester eScholar ID:
uk-ac-man-scw:179446
Created by:
Burns, Alistair
Created:
16th October, 2012, 12:02:03
Last modified by:
Burns, Alistair
Last modified:
8th October, 2014, 05:33:06

Can we help?

The library chat service will be available from 11am-3pm Monday to Friday (excluding Bank Holidays). You can also email your enquiry to us.