Resilience in the Bi-Multilingual Brain

Abstract

Bi-/multilingualism has been suggested to aid cognitive functioning across the lifespan by improving resilience to age-related cognitive decline. It has been argued that multilingual engagement places unique requirements on attentional and inhibitory control processes in the brain, which again could potentially change the structure and functional dynamics of the brain. This thesis aims to explore how multilingual diversity (MLD) can relate to cognitive performance and baseline neural activity by measuring resting-state (RS) EEG power in healthy bi/multilingual Norwegian-English adults across multiple stages of adulthood. Furthermore, behavioral data were collected using a non-linguistic flanker task to evaluate attentional control. The primary effects of MLD on EEG power in the alpha and theta frequency bands were found to be negative in the current analyses. This suggests that increased multilingual engagement may counteract the conventional age-related increases in brain baseline activity. Those of older age had significantly slower response times (RTs), however, MLD was not associated with improved flanker task performance. Results also showed no distinguishable relationship between the flanker task performance and RS EEG power. While these findings are not immediately noticeable in attentional task performance, these suggest that increased multilingual engagement has the potential to slow down age-related neural changes and assist in maintaining baseline brain activity as we age.

Bi-/multilingualism has been suggested to aid cognitive functioning across the lifespan by improving resilience to age-related cognitive decline. It has been argued that multilingual engagement places unique requirements on attentional and inhibitory control processes in the brain, which again could potentially change the structure and functional dynamics of the brain. This thesis aims to explore how multilingual diversity (MLD) can relate to cognitive performance and baseline neural activity by measuring resting-state (RS) EEG power in healthy bi/multilingual Norwegian-English adults across multiple stages of adulthood. Furthermore, behavioral data were collected using a non-linguistic flanker task to evaluate attentional control. The primary effects of MLD on EEG power in the alpha and theta frequency bands were found to be negative in the current analyses. This suggests that increased multilingual engagement may counteract the conventional age-related increases in brain baseline activity. Those of older age had significantly slower response times (RTs), however, MLD was not associated with improved flanker task performance. Results also showed no distinguishable relationship between the flanker task performance and RS EEG power. While these findings are not immediately noticeable in attentional task performance, these suggest that increased multilingual engagement has the potential to slow down age-related neural changes and assist in maintaining baseline brain activity as we age.