Individual differences in the neural processing of sentences in Portuguese- English bilinguals: an fMRI study of reading comprehension effects on brain activation

Abstract

This article presents part of a dissertation that aimed at investigating monolingual and bilingual brains and their neuroanatomical response to the processing of written sentences. For this article, we concentrate on the objective of exploring whether individual differences, namely proficiency in the L2 and working memory capacity (WMC), modulate brain activation in 12 Brazilian Portuguese-English late bilinguals. Results corroborate the hypothesis that more proficient bilinguals would engage the usual route for comprehension (increased activation in the left superior temporal region) while lower proficient participants would resort to more right-lateralized areas. Lower WMC bilinguals, besides recruiting more right-lateralized areas, relied on less proficient processes to comprehend sentences than higher WMC bilinguals. The study adds evidence to the idea that the processing of sentences, the connections between words in the L2 and the semantic representations of the L1 strengthen as proficiency in the L2 increases.