The thesis presents a multi-aspectual analysis of simplified fiction at the B2 and C1 levels and their original counterparts. It aims to explore the simplification and language transformation performed on authentic texts to adapt them to particular CEFR levels. The thesis also endeavors to provide an insight into whether there are common linguistic features that characterize authentic and adapted texts of different levels, thus helping teachers and learners justify their choice between original and simplified texts. Based on the theoretical framework, the thesis provides an analysis of a specialized corpus of six texts which is comprised of the first chapters of the two original novels and their simplified versions adapted to the B2 and C1 levels by two different publishers. Each sample was subjected to scrutiny of selected linguistic features, thus unveiling the tendencies in the language, discourse, and information control in the graded readers. Consequently, the results of the text analysis were contrasted with CEFR to compare the actual text complexity with its assigned CEFR level. The results of the analysis seem to indicate certain discrepancies in this respect. Keywords: CEFR, specialized corpus, graded readers, authentic texts, simplification, language control, discourse control,...

L'objectif de la présente thèse de doctorat était d'étudier la relation entre le bilinguisme et le contrôle exécutif général. Les recherches sur le bilinguisme en psycholinguistique ont montré que la co-activation permanente des langues ainsi que la nécessité de s'adapter à l'environnement linguistique peuvent produire un renforcement des capacités de contrôle chez les bilingues. Toutefois, la nature des processus de contrôle impliqués reste controversée. Trois études ont examiné cette question au niveau neuronal chez des bilingues tardifs français-allemand. Différentes tâches expérimentales mettant en jeu un conflit cognitif ont été utilisées, les unes impliquant une composante linguistique (Stroop et amorçage négatif), et une autre impliquant une composante motrice (antisaccades). Les principaux résultats sont les suivants : (1) Renforcement des processus de gestion de conflits et d'inhibition chez les bilingues, (2) Interaction entre le cortex cingulaire antérieur et le cortex préfrontal dans le contrôle cognitif plus efficace chez les bilingues que chez les monolingues et (3) Modulation du contrôle exécutif par divers facteurs linguistiques individuels inhérents au bilinguisme. Prises dans leur ensemble, ces observations corroborent l'hypothèse d'une implication de processus de contrôle général dans le bilinguisme et révèlent des capacités d'adaptation neuroplastique en fonction des contraintes linguistiques. / The present doctoral thesis aimed to study the relation between bilingualism and domain-general executive control. Psycholinguistic research on bilingualism has shown that the sustained co-activation of languages and the need to adapt to the linguistic environment lead to a reinforcement of control abilities in bilinguals. However, the nature of domain-general executive control involvement in multiple language use is a matter of debate. Three studies were conducted in order to investigate this issue at the neuronal level in French-German late bilinguals. Different experimental tasks involving a cognitive conflict were used, certain of them involving a linguistic component (Stroop and negative priming) and the other one involving a motoric component (antisaccade). The main findings collected in the present doctoral thesis showed (1) the behavioral and neurophysiological evidence of enhanced conflict monitoring and inhibition in bilinguals, (2) the more efficient dynamic interplay between the anterior cingulate cortex and the prefrontal cortex in executive control in bilinguals in comparison with monolinguals, and (3) a modulation of executive control by the individual linguistic factors inherent to bilingualism. Taken together, the present findings support psycholinguistic theories postulating domain-general control involvement in bilingualism and reveal the capacity of neuroplastic adaptation as a function of linguistic constraints.