Poster E44, Thursday, August 22, 2019, 3:45 – 5:30 pm, Restaurant Hall
Language entropy: A novel quantification of language experience among bilinguals
Jason Gullifer1,3, Shanna Kousaie1,3, Annie Gilbert1,3, Nathalie Giroud2,3, Angela Grant2,3, Kristina Coulter2,3, Denise Klein1,3, Shari Baum1,3, Natalie Phillips2,3, Debra Titone1,3;1McGill University, 2Concordia University, 3Centre for Research on Brain, Language and Music
Bilinguals vary in their language usage across communicative contexts, which holds consequences for language and executive control more broadly. Theoretical and empirical studies in the neurocognition of bilingualism capture some of this variability, but there remains a focus on static measures like age of acquisition and one-dimensional measures like current exposure to a second language. Recently, we have developed a novel measure that captures additional variability in bilingual language experience: language diversity formalized as entropy. Language entropy is computed from questionnaire data about language usage in various communicative contexts. Language entropy characterizes individuals’ language diversity on a continuum from compartmentalized (single language use; low entropy/diversity) to integrated (balanced, dual language use; high entropy/diversity). Previously, we have shown that, in the aggregate, language entropy relates to resting-state organization of functional brain networks that underlie proactive executive control abilities (Gullifer et al., 2018). Crucially, principal component analysis indicates that language entropy in professional contexts is independent from language entropy in other communicative contexts (at least for samples of bilinguals from Montreal, Canada). These independent components both relate to self-reported L2 abilities over and above classic measures alone (Gullifer and Titone, in press). Our goal here is to replicate and extend previous findings using a new sample of bilingual participants (N = 62). Participants from Montreal who speak French and English completed an expanded language history questionnaire that probes information about language usage and exposure across 16 usage contexts. These contexts may have different constraints for language control to the extent that they emphasize comprehender-driven communication (e.g., writing for an audience, speaking in a professional context, etc.) vs. speaker-driven or internal language usage (e.g., language used for dreaming, counting, etc.). A subset of the participants also completed the AX continuous performance task (AX-CPT), which measures proactive executive control abilities. Results show that language entropy for the sample can be decomposed into three components: inner/social entropy, non-interactive entropy, and professional entropy. In turn, only non-interactive and professional entropy components related to performance on the AX-CPT: higher component scores related to increased engagement of proactive executive control. Thus, the findings are compatible with previous work showing that high language entropy, reflecting balanced bilingual language usage, relates to greater engagement of proactive executive control (Gullifer et al., 2018), perhaps resulting from increased competition between the two languages for bilinguals who exhibit integrated language usage (Green & Abutalebi, 2013). These results extend previous findings by showing that some types of language usage (i.e., non-interactive and professional usage) appear to drive these results more than others. The next step is to assess how the different language entropy components relate to resting-state functional connectivity, as a subset of these participants also underwent resting-state MRI scans.
Themes: Multilingualism, Methods
Method: Behavioral