Moderating effect of cognitive reserve on brain integrity and cognitive performance

Monica E Nelson; Britney M Veal; Ross Andel; Julie Martinkova; Katerina Veverova; Hana Horakova; Zuzana Nedelska; Jan Laczó; Martin Vyhnalek; Jakub Hort

doi:10.3389/fnagi.2022.1018071

Moderating effect of cognitive reserve on brain integrity and cognitive performance

Front Aging Neurosci. 2022 Nov 3:14:1018071. doi: 10.3389/fnagi.2022.1018071. eCollection 2022.

Authors

Affiliations

¹ School of Aging Studies, University of South Florida, Tampa, FL, United States.
² Edson College of Nursing and Health Innovation, Arizona State University, Phoenix, AZ, United States.
³ Department of Neurology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czechia.

Abstract

Background: Dementia syndrome is one of the most devastating conditions in older adults. As treatments to stop neurodegeneration become available, accurate and timely diagnosis will increase in importance. One issue is that cognitive performance sometimes does not match the corresponding level of neuropathology, affecting diagnostic accuracy. Cognitive reserve (CR), which can preserve cognitive function despite underlying neuropathology, explains at least some variability in cognitive performance. We examined the influence of CR proxies (education and occupational position) on the relationship between hippocampal or total gray matter volume and cognition.

Methods: We used data from the Czech Brain Aging Study. Participants were clinically confirmed to be without dementia (n = 457, including subjective cognitive decline and amnestic mild cognitive impairment) or with dementia syndrome (n = 113).

Results: For participants without dementia, higher education magnified the associations between (a) hippocampal volume and executive control (b = 0.09, p = 0.033), (b) total gray matter volume and language (b = 0.12, p < 0.001), and (c) total gray matter volume and memory (b = 0.08, p = 0.018). Similarly, higher occupational position magnified the association between total gray matter volume and (a) attention/working memory (b = 0.09, p = 0.009), (b) language (b = 0.13, p = 0.002), and (c) memory (b = 0.10, p = 0.013). For participants with dementia, the associations between hippocampal (b = -0.26, p = 0.024) and total gray matter (b = -0.28, p = 0.024) volume and visuospatial skills decreased in magnitude with higher education.

Conclusion: We found that the association between brain volume and cognitive performance varies based on CR, with greater CR related to a stronger link between brain volume and cognition before, and a weaker link after, dementia diagnosis.

Keywords: MRI; attention/working memory; executive control; language; visuospatial skills.