Interhemispheric connectivity upon presentation of a bilingual stimulus: A longitudinal neurolinguistic EEG study

The methods of foreign language teaching available on the market of educational services require transparent and standardized evaluation in terms of the presence of the effect claimed by their creators. Such evaluation would facilitate the таchoice of an appropriate method for both individuals and government institutions. In this study, we propose metrics that, within the framework of a more general methodology, will make it possible to reliably establish whether a particular method of foreign language teaching has an effect on the linguistic performance of students. The proposed metrics are based on measuring the connectivity between individual areas of the cerebral cortex of students when recording an electroencephalogram (EEG) during the performance of language tasks. The language tasks involve categorization of proposed translations for German sentences depending on their correctness or incorrectness and the degree of the respondent’s confidence. Based on the indicators of connectivity, one can indirectly assess the number of areas of the cerebral cortex involved in the solution of a cognitive task, as well as assess the individual and group features of the interaction between these areas which may be related to the cognitive strategies that students use to solve a linguistic problem. We analysed EEG recordings obtained during two experimental sessions (with a month-long interval between them) in two groups of subjects: the first group was taught German according to the standard method, and the second group, according to the deep semantics method of P. Y. Galperin. The epochs for the analysis contained brain responses to two novel stimuli presented at the same time: a sentence in German (to translate) and in Russian (a translation version). In this paper, we describe the testing of a method which is based on the selected metrics and aimed at accentuating the difference, at the neurophysiological level, between groups of students using different teaching approaches.