Brain network activity in monolingual and bilingual older adults. (January 2015)

• Record Type: Journal Article
• Authors: Grady, Cheryl L.; Luk, Gigi; Craik, Fergus I.M.; Bialystok, Ellen
• Is Part Of: Neuropsychologia. Volume 66(2015)
• Page Start: 170
• Page End: 181
• Publication Date: 2015-01
• Subjects: Aging -- Cognitive control -- Functional connectivity -- Frontoparietal control network -- Default mode network -- Language; Neuropsychology -- Periodicals; Neurology -- Periodicals; Psychophysiology -- Periodicals; Neuropsychologie -- Périodiques; Neuropsychology; Periodicals; Electronic journals; 616.8
• DOI: 10.1016/j.neuropsychologia.2014.10.042
• Languages: English
• ISSNs: 0028-3932

Abstract

Abstract: Bilingual older adults typically have better performance on tasks of executive control (EC) than do their monolingual peers, but differences in brain activity due to language experience are not well understood. Based on studies showing a relation between the dynamic range of brain network activity and performance on EC tasks, we hypothesized that life-long bilingual older adults would show increased functional connectivity relative to monolinguals in networks related to EC. We assessed intrinsic functional connectivity and modulation of activity in task vs. fixation periods in two brain networks that are active when EC is engaged, the frontoparietal control network (FPC) and the salience network (SLN). We also examined the default mode network (DMN), which influences behavior through reduced activity during tasks. We found stronger intrinsic functional connectivity in the FPC and DMN in bilinguals than in monolinguals. Although there were no group differences in the modulation of activity across tasks and fixation, bilinguals showed stronger correlations than monolinguals between intrinsic connectivity in the FPC and task-related increases of activity in prefrontal and parietal regions. This bilingual difference in network connectivity suggests that language experience begun in childhood and continued throughout adulthood influences brain networks in ways that may provide benefits in later life. Highlights: Functional connectivity (FC) in the frontoparietal control network is stronger in bilinguals. FC in the FPC is correlated in bilinguals with greater modulation of task-positive activity. Language experience influences brain networks in ways that may provide benefits in later life.