Does bilingualism influence neuropsychological test performance in older adults? A systematic review

Abstract

Objective: Using standardized tests which have been normed on monolinguals for the assessment of bilinguals presents challenges to the accurate characterization of cognitive profile as the literature provides compelling evidence for the influence of bilingualism on cognitive abilities. However, little is known about the generalizability of these findings to clinical neuropsychology. The aim of this review was to address this gap by summarizing current evidence on the performance of bilingual older adults on standardized tests routinely used in clinical practice. Method: A systematic search of Web of Science, PsycINFO and PubMed was conducted. 27 crosssectional and longitudinal studies which use at least one standardized neuropsychological test for cognitive impairment were included in the review. Potential demographic (cultural/linguistic background of the participants, immigrant status), clinical (diagnostic status), and methodological confounders (language of test administration, components of bilingualism) were also examined. The review protocol was registered at the PROSPERO International Prospective Register of Systematic Review with registration number CRD42018114658. Results: The results of this review revealed some bilingual advantage on measures of inhibitory control and bilingual disadvantage on measures of verbal fluency in cross-sectional studies. Bilingualism status was not associated with test performance in longitudinal studies. However, findings lack consistency due to demographic variables and methodological differences across studies. Conclusion: Neuropsychological tests assessing language domains and, to some extent executive function act as clinically relevant features of bilingualism for neuropsychological evaluation. However, immigration status, acculturation level and language of test administration needs to be taken into account when assessing bilingual older adults.

Effects of Sociodemographic Variables and Depressive Symptoms on MoCA Test Performance in Native Germans and Turkish Migrants in Germany

“…This result indicated that the level of acculturation and integration differed (with those picking German being more integrated) and that this level was associated with cognitive performance. Another systematic review on bilingualism as an influencing factor in test performance in older adults indicates that migration status, acculturation level, and language of neuropsychological testing need to be considered when assessing bilingual older adults [ 48 ]. In line with this, the systematic review on migration and cognition conducted by Xu et al (2017) [ 9 ] demonstrated a significant association between a higher level of acculturation and better performance in cognitive functioning among migrants.…”

Geographic variability in limited English proficiency: A cross-cultural study of cognitive profiles

“…Assuming normative performance in examinees with LEP on nonverbal tests on rational grounds alone increases the risk of significant errors in the clinical interpretation of scores (Celik et al, 2020; Funes et al, 2016; Gasquoine & Gonzales, 2012). In fact, our results challenge the notion of “LEP profile” as a unitary construct.…”

“…Recent research demonstrated that LEP can be a significant confound in test result interpretation even in cognitively high-functioning examinees (Ali, Brantuo, et al, 2022; Erdodi et al, 2017a). Consequently, existing norms may not apply to individuals with LEP (Celik et al, 2020; Funes et al, 2016; Gasquoine & Gonzales, 2012), as they systematically underestimate verbal skills in general – while perhaps providing an accurate measure of English proficiency. As the world grows diverse due to migration and the percentage of bilinguals increases both in Europe and the USA (Eurostat, 2018; Ryan, 2013), so do the chances of encountering patients with LEP in clinical settings.…”

“…Recent reviews (Antoniou, 2019; Celik et al, 2020) have outlined bilinguals’ advantages and disadvantages in different cognitive tasks. The tasks’ level of verbal mediation further complicates the interpretation of cognitive profiles associated with LEP.…”

Bilingualism, assessment language, and the Montreal Cognitive Assessment in Mexican Americans

“…Studies also vary with regard to the cognitive instruments used and domains assessed. The MoCA is a relatively brief cognitive screening instrument, and may not be sensitive to detect possible subtle cognitive advantages in language and executive functioning, which may be more reliably associated with bilingual advantages when these relationships are observed 25 …”