Neural changes underlying successful second language word learning: An fMRI study

Abstract

a b s t r a c tA great deal of research has examined behavioral performance changes associated with second language learning. But what changes are taking place in the brain as learning progresses? How can we identify differences in brain changes that reflect successes of learning? To answer these questions, we conducted a functional magnetic resonance imaging (fMRI) study to examine the neural activities associated with second language word learning. Participants were 39 native English speakers who had no prior knowledge of Chinese or other tonal language, and were trained to learn a novel tonal vocabulary in a six-week training session. Functional MRI scans as well as behavioral performances were obtained from these learners at two different times (pre-and post-training). We performed region of interest (ROI) and connectivity analyses to identify effective connectivity changes associated with success in second language word learning. We compared a learner group with a control group, and also examined the differences between successful learners and less successful learners within the learner group across the two time points. Our results indicated that (1) after training, learners and non-learners rely on different patterns of brain networks to process tonal and lexical information of target L2 words; (2) within the learner group, successful learners compared to less successful learners showed significant differences in language-related regions; and (3) successful learners

On neural correlates of individual differences in novel grammar learning: An fMRI study

“…Moreover, already in the early 1900s, the left lower parietal region was delineated as the "language talent area" by the German neurologist Pötzl (1925), who pointed it out to be the site underlying the exceptionality of the brains of multilinguals (Della Rosa et al, 2013). His findings seem to converge with recent neuroimaging investigations: the inferior parietal cortex has been shown to play a crucial role in complex language functions and memory processes, phonological representation, semantic integration, and second language vocabulary learning (Della Rosa et al, 2013;Li, Legault, & Litcofsky, 2014;Mechelli et al, 2004;Yang, Gates, Molenaar, & Li, 2015). More specifically, O'Connor, Han, & Dobbins (2010) have found the angular and supramarginal gyri to act as markers of violations in memory expectations, where a violation is a sign of contradiction between retrieval outcomes and expectations, and argued for the importance of both superior and inferior aspects of the lateral parietal regions for noting a lack of correspondence between what is anticipated from memory retrieval, and what is unusual.…”

Intrinsic Functional Connectivity in the Adult Brain and Success in Second-Language Learning

“…For example, the WM microstructure of the left arcuate fasciculus, which connects the left IFG with left IPL and STG, has been associated with novel word learning (Ló pez-Barroso et al, 2013). Yang et al (2015) showed that successful compared with less successful learners of novel words had stronger connectivity within the left IFG-IPL-STG circuit during a word-picture association task. Gray matter density of the left IFG was corrected positively with L2 lexical efficiency, measured by the number of words produced in a timed verbal fluency task, whereas gray matter density of the supramarginal gyrus reflected the number of words known (Grogan et al, 2012).…”

The nature of the language input affects brain activation during learning from a natural language

“…The inferior parietal region, along with the temporal lobe, is consistently active in semantic processing tasks (Binder & Desai, 2011; Price, 2010) and the inferior parietal regions in particular become better integrated into a larger word-learning network for learners who are able to successfully associate phonological strings with meaning (Yang, Gates, Molenaar, & Li, 2015). However, our task did not provide learners with any semantic information for the words contained in the input.…”