Neurocognitive mechanisms of mathematics vocabulary processing in L1 and L2 in South African first graders: An fNIRS study

SignificanceTo learn mathematics, young children require accurate interpretations of mathematics vocabulary. When school language differs from childrens home language, mathematics performance often decreases. Little is known about cortical activation during mathematics vocabulary processing in different languages. This insight will help us to better understand childrens mathematical learning in multilingual societies. Aim and approachWe investigated behavioral and brain responses (fNIRS) of 42 isiZulu and Sesotho (L1) first graders (6.75-7.83 years, 22 girls) who learn mathematics in English (L2) at school when they encounter mathematics vocabulary in L2 compared to L1; and mathematics vocabulary compared to object recognition in L1. ResultsThe results show that higher accuracy in the L1 mathematics vocabulary, as compared to the L2 mathematics vocabulary, comes with the costs of higher cognitive demands in the right superior and middle frontal gyri for first graders. Mathematics vocabulary required longer response time than object recognition and a higher activation in the right superior frontal gyrus. No parietal difference was observed between conditions. ConclusionsFirst graders with no automatization of mathematics vocabulary processing, still demand frontal cognitive resources. This study is a good example of how educational neuroimaging compliments our interpretation of behavioral outcomes and environmental factors such as multilingualism.