Typology of multilinguals’ languages and its relation to brain and cognition

Olga Kepinska : Universität Wien

Learning and using additional languages has been time and again shown to be related to functional and structural changes to the brain. One aspect of multilingualism that has not been examined systematically so far is the typology of multilinguals’ languages: Do differences and similarities between languages multilinguals know contribute to the development of their cognition and brain? In this talk, I will discuss a methodology for describing the continuum of multilingual language experience that accounts for typological distance. We applied it in two studies with groups with diverse language backgrounds. In the first, we investigated n = 162 5-6-year-olds with various language backgrounds on a monolingual-to-quintilingual continuum. Overlaps in lexical distances between participants’ languages were found to be related to aspects of their dominant-language lexical knowledge and to brain activation patters during a dominant-language lexical task. In the second study, we looked at typological distance at the level of phonology and its relation to brain structure. In particular, we investigated how neuroanatomical indices describing the transverse temporal gyrus (TTG, cortical structure housing early auditory cortex) were related to cross-linguistic phonological information of n = 136 adult participants exposed to between 1 to 7 languages. We found that language experience with phonologically distant languages was associated with cortical thickness of the second TTG. These results refine our understanding of the neural underpinnings of multilingual language experience and will be discussed in the larger context of genetic versus environmental influences on the brain.