Lecture | LACG Meetings
A tale of two spectra: Language experiences and neurocognitive adaptations
- Vincent DeLuca, Jason Rothman & Toms Voits
- Thursday 18 March 2021
- LACG Meetings
Much research over the past two decades shows that bilingualism affects brain structure, function, and potentially domain-general cognition (see e.g., Bialystok 2016; Pliatsikas 2019). The specificity of these effects, however, has become the subject of significant debate in recent years, in large part due to variability of findings across studies (see Leivada et al. 2020 for review). In this talk, we will introduce our research programs within the Psycholinguistics of Language Representation (PoLaR) lab that addresses the juxtaposition of data and argumentation. Our work is guided by the principle that although bilingual effects are existent, they are conditional. In other words, bilingualism per se is not a sufficient condition for relevant effects on neurocognition. We will review our work that is generally designed to test the hypothesis that specific experience-based factors (EBFs) variably affect neural activity and plasticity in brain regions and pathways implicated in language- and executive control across the lifespan.
We present results from a series of MRI studies showing a specificity of neural adaptations to different EBFs (DeLuca, Rothman & Pliatsikas, 2019; DeLuca, Rothman, Bialystok & Pliasikas, 2019, 2020a,b) in younger adults. We will also present data from older adults, showing similar EBF effects in healthy cognitive ageing (Voits, Robson, Rothman & Pliasikas, submitted) and with mild cognitive impairment Voits, et al. in prep.). EBFs related to duration of bilingual language use correlate to neurocognitive adaptations suggesting increased efficiency in language control, whereas those related to extent of additional language use correlate with adaptations suggesting increased control demands. Considered together, these data suggest that the brain strives to be maximally effective and efficient in language processing and control, which in turn affects domain-general cognitive processes proportionally to degree of engagement with bilingual experiences. The work in older populations leads to the conclusion that degree of engagement with bilingualism is a catalyst for cognitive/brain reserve and thus has some real-world benefits in aging. Time permitting, we will briefly present the framework of a newly submitted grant proposal, Cognitive Aging and Bilingual Experience Effects (CABEE), which seeks to push forward our work on typical and pathological cognitive aging and neurodegeneration across a series of (some new) methods and approaches, including intervention.