Die Abbildung des mehrsprachigen Sprachsystems im Gehirn: Zum Einfluss verschiedener Variablen

One of the main questions in multilingualism research concerns the shared or separate representation of languages in the mind and in the brain. Behavioral data, and data from aphasia studies as well as from functional imaging studies support both hypotheses. Here, I concentrate on the functional imaging studies with healthy bi- or multilinguals in an attempt to define the variables and their influence on the representation of two or more languages in the brain. Up to date five factors can be distinguished. The modality (language production vs. language perception) and the level of language processing tested (single words, sentence, text) play an important role in this respect, so do age of acquisition and proficiency, which were the specific focus of investigation in some of the studies. Age of acquisition appears to be the more determinant factor in language production, while proficiency may have a more critical effect in language perception. In addition, some studies reveal differences in the activation patterns between languages and between groups of subjects reflecting the employment of different processing strategies.