Effects of four-month-long foreign language learning on executive functions and white matter integrity in older adults
Authors: Bubbico Giovanna , Grundy John G. , Navarra Riccardo , Caporale Alessandra Stella , Candita Chiara , Bouraimis Michela , Felice Miriam , Chiacchiaretta Piero , Granzotto Alberto , Tartaro Armando , Ferretti Antonio , Perrucci Mauro Gianni 
Published: September 2023

Objective

Bilingualism has been associated with cognitive benefits and a potential protective effect against neurodegenerative conditions. Previous research has shown that bilingual individuals exhibit greater white matter integrity compared to monolinguals of the same age. However, the impact of foreign-language learning on brain structure in older adults during the initial stages of language acquisition remains uncertain. This study aimed to investigate the cognitive and structural effects of a four-month-long foreign language learning program in a group of healthy monolinguals older adult.

Materials and Methods

Thirteen Italian-speaking participants (aged 59-78) underwent a four-month intensive English course for beginners. Pre- and post-assessments were conducted to evaluate executive cognitive functions, as well as diffusion tensor imaging (DTI) to examine brain structural changes.

Results

The study findings showed substantial increases in axial, radial, and mean diffusivity during the four-month language learning period. The most prominent variations were observed in key brain regions, namely the fronto-occipital fasciculus, the superior longitudinal fasciculus, and the corpus callosum areas. Notably, brain-behaviour correlations indicated a robust positive relationship between changes in axial diffusivity and performance on the Stroop task, a well-established measure of cognitive interference inhibition.

Conclusions

These findings suggest that a four-month foreign language learning program can lead to structural changes in the brain, particularly affecting white matter integrity and that these structural changes are associated with improvements in executive functions. The study underscores the potential of brief language learning interventions to influence brain structure and enhance cognitive abilities in older adults.

Highlights

Bilingualism is associated with cognitive advantages and the potential for protection against neurodegenerative conditions, as evidenced by bilingual individuals displaying enhanced white matter integrity compared to individuals who are monolingual and of the same age.

The study investigates how a four-month foreign language learning program affects brain structure in older adults during the initial stages of language acquisition

The research reveals significant increases in axial, radial, and mean diffusivity in key brain regions, including the fronto-occipital fasciculus, superior longitudinal fasciculus, and corpus callosum, during the language learning period.

The study demonstrates a positive link between changes in axial diffusivity and performance on the Stroop task, indicating that short language learning interventions can lead to structural brain changes associated with improved executive functions in older adults.