Abstract
Objectives
Experience-related neuroplasticity suggests that bilinguals who actively manage their two languages would develop more efficient neural organization at brain regions related to language control, which also overlap with areas involved in executive control. Our aim was to examine how active bilingualism—manifested as the regular balanced use of two languages and language switching—may be related to the different domains of executive control in highly proficient healthy older adult bilinguals, controlling for age, processing speed, and fluid intelligence.
Methods
Participants were 76 community-dwelling older adults who reported being physically and mentally healthy and showed no signs of cognitive impairment. They completed a self-report questionnaire on their language background, two computer measures for previously identified covariates (processing speed as measured by two-choice reaction time (RT) task and fluid intelligence as measured by the Raven’s Progressive Matrices), as well as a battery of computerized executive control tasks (Color-shape Task Switching, Stroop, Flanker, and Spatial 2-back task).
Results
Regression analyses showed that, even after controlling for age, processing speed, and fluid intelligence, more balanced bilingualism usage and less frequent language switching predicted higher goal maintenance (nonswitch trials RT in Color-shape Task Switching) and conflict monitoring abilities (global RT in Color-shape Task Switching and Flanker task).
Discussion
Results suggest that active bilingualism may provide benefits to maintaining specific executive control abilities in older adult bilinguals against the natural age-related declines.
A Tweaking Principle for Executive Control: Neuronal Circuit Mechanism for Rule-Based Task Switching and Conflict Resolution
