Bridging interpersonal and ecological dynamics of cognition through a systems framework of bilingualism.

Human cognition occurs within social contexts, and nowhere is this more evident than language behavior. Regularly using multiple languages is a globally ubiquitous individual experience that is shaped by social environmental forces, ranging from interpersonal interactions to ambient language exposure. Here, we develop a , where embedded layers of individual, interpersonal, and ecological sociolinguistic factors jointly predict people's language behavior. Of note, we quantify interpersonal and ecological language dynamics through the novel applications of language-tagged social network analysis and geospatial demographic analysis among 106 English-French bilingual adults in Montréal, Canada. Consistent with a Systems view, we found that people's individual language behavior, on a global level (i.e., overall language use), was jointly predicted by the language characteristics of their interpersonal social networks and the ambient linguistic patterns of their residential neighborhood environments, whereas more granular aspects of language behavior (i.e., word-level proficiency) was mainly driven by local, interpersonal social networks. Together, this work offers a novel theoretical framework, bolstered by innovative analytic techniques to quantify complex social information and empower more holistic assessments of multifaceted human behaviors and cognition, like language. (PsycInfo Database Record (c) 2022 APA, all rights reserved).