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Part of
Bilingualism, Executive Function, and Beyond: Questions and insights
Edited by Irina A. Sekerina, Lauren Spradlin and Virginia Valian
[Studies in Bilingualism 57] 2019
► pp. 355–369

Chapter 21
Does bilingualism protect against cognitive aging?

Methodological issues in research on bilingualism, cognitive reserve, and dementia incidence

| University of California, San Diego
| Columbia University
| University of Michigan

Recent studies of bilingualism as a protective factor in cognitive aging have reported conflicting findings, and researchers have begun to explore the methodological complications that may explain differences across studies. This article details the current research landscape and addresses several issues relevant to the study of bilingualism and late-life cognitive function: study design, establishing causal relationships, confounding factors, operationalizing bilingualism, predicting cognitive level versus cognitive change, and incorporating brain structural variables to interrogate cognitive reserve.

Keywords: cognitive aging trajectories, bilingualism and dementia, cognitive reserve
Article outline
  • 1.Introduction
  • 2.The current research landscape of AD studies
  • 3.Study design, causal inference, and confounding factors
  • 4.Operationalizing bilingualism for research on cognitive aging and dementia
  • 5.Predicting cognitive level versus age-related cognitive change
  • 6.Incorporating brain structural variables
  • 7.Summary and methodological recommendations
  • References
Published online: 12 June 2019
DOI logo
https://doi.org/10.1075/sibil.57.21wat
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