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Cognitive Reserve Capacity: Exploring and Validating a Theoretical Model in Healthy Ageing

Published online by Cambridge University Press:  07 May 2019

Lisa McGarrigle*
Affiliation:
School of Nursing and Human Sciences, Faculty of Science and Health, Dublin City University (DCU), Dublin, Ireland Division of Geriatric Medicine, Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
Kate Irving
Affiliation:
School of Nursing and Human Sciences, Faculty of Science and Health, Dublin City University (DCU), Dublin, Ireland
Martin P.J. van Boxtel
Affiliation:
Department of Psychiatry and Neuropsychology, School of Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
Lorraine Boran
Affiliation:
School of Nursing and Human Sciences, Faculty of Science and Health, Dublin City University (DCU), Dublin, Ireland
*
*Correspondence and reprint requests to: Lisa McGarrigle, Dalhousie University, Veterans’ Memorial Building, Suite 1314, 5955 Veterans’ Memorial Lane, Halifax, Nova Scotia, B3H 2E1, Canada. E-mail: lisa.mcgarrigle@dal.ca

Abstract

Objective: Cognitive reserve (CR) capacity can be viewed as the maximum processing potential of neural systems that support adaptive cognitive performance in age-related cognitive decline. CR is a complex construct that can only be measured indirectly. Proxy measures (e.g., psychosocial/lifestyle variables) are traditionally used to reflect CR. However, strong relationships have been observed between these measures and cognitive functions (e.g., executive function [EF], processing resources [PR], fluid/crystallized abilities); therefore, the organizational structure of indicators implicated in CR remains unclear. The objective of this study was to test a hypothetical, theoretical model of CR capacity that includes both traditional CR proxy indicators and measures of cognitive function [Satz et al. (2011). Journal of Clinical and Experimental Neuropsychology, 33(1), 121–130], which remain, as yet, untested. Method: Construct validity of the model was investigated in healthy older adults through exploratory and confirmatory factor analysis (EFA and CFA) using data from the Maastricht Ageing Study (MAAS). A secondary CFA was conducted to validate the model using data from the Irish Longitudinal Study on Ageing (TILDA). Results: EFA and CFA in MAAS established a two-factor model comprising EF/PR and cumulative cognitive enrichment (CCE), which was further validated in a secondary analysis in TILDA. Convergent and discriminant validity was supported in MAAS (range of R2 = .228–.635; factor correlation confidence interval (CI) = .622, .740) and TILDA (range of R2 = .172–.899; factor correlation CI = .559, .624). Conclusions: A dual model of CR elucidated the relationships between hypothesized indicators of CR capacity and revealed a two-factor structure suggesting that both control (EF/PR) and representational processes (CCE) are involved in CR capacity.

Type
Regular Research
Copyright
Copyright © INS. Published by Cambridge University Press, 2019. 

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