Testing for the myth of cognitive reserve: are the static and dynamic cognitive reserve indexes a representation of different reserve warehouses?

Serra, Laura, Petrosini, Laura, Salaris, Andrea, Pica, Lorenzo, Bruschini, Michela, Di Domenico, Carlotta, Caltagirone, Carlo, Marra, Camillo and Bozzali, Marco (2019) Testing for the myth of cognitive reserve: are the static and dynamic cognitive reserve indexes a representation of different reserve warehouses? Journal of Alzheimer's Disease, 72 (1). pp. 111-126. ISSN 1387-2877

[img] PDF - Accepted Version
Download (1MB)

Abstract

BACKGROUND
Cognitive reserve (CR) explains the individual resilience to neurodegeneration. Years of formal education express the static measure of reserve (sCR). A dynamic aspect of CR (dCR) has been recently proposed.

OBJECTIVE
The aim of the study was to compare sCR and dCR indexes, respectively, to detect brain abnormalities in Alzheimer's disease (AD) patients.

METHODS
117 individuals [39 AD, 40 amnestic mild cognitive impairment (aMCI), 38 healthy subjects (HS)] underwent neuropsychological evaluation and a 3T-MRI. T1-weighted volumes were used for manual segmentation of the hippocampus and of the parahippocampal cortices. Years of formal education were used as an index of sCR. Partial Least Square analysis was used to decompose the variance of individual MMSE scores, considered as a dCR index. In aMCI and AD patients, the brain abnormalities have been assessed comparing individuals with high and low levels of sCR and dCR in turn. Moreover, we investigated the effect of the different CR indexes in mediating the relationship between changes in brain volumes and memory performances.

RESULTS
sCR and dCR indexes classified differently individuals having high or low levels of CR. Smaller hippocampal and parahippocampal volumes in high dCR patients were found. The sCR and dCR indexes mediated significantly the relationship between brain abnormalities and memory in patients.

CONCLUSIONS
CR mediated the relationship between brain and memory dysfunctions. We hypothesized that sCR and dCR indexes are a representation of different warehouses of reserve not operating in parallel but forming a complex system, in which crystalized cognitive abilities and actual cognitive efficiency interact with brain atrophy impacting on memory.

Item Type: Article
Keywords: Alzheimer’s disease, dynamic and static cognitive reserve, hippocampus, mild cognitive impairment, parahippocampal gyrus
Schools and Departments: Brighton and Sussex Medical School > Neuroscience
Subjects: R Medicine > RC Internal medicine > RC0321 Neurosciences. Biological psychiatry. Neuropsychiatry > RC0346 Neurology. Diseases of the nervous system Including speech disorders
Related URLs:
Depositing User: Patricia Butler
Date Deposited: 18 Feb 2020 14:01
Last Modified: 18 Feb 2020 14:30
URI: http://sro.sussex.ac.uk/id/eprint/89968

View download statistics for this item

📧 Request an update