In recent decades, there has been a significant decline in the number of Low German native speakers, and Low German can now only be found in the context of High German-Low German bilingualism. However, the degree of endangerment of Low German depends not only on the absolute or relative number of speakers, but also on whether there is a balanced bilingualism with a division of functions between the two languages or whether one of the two languages dominates an increasing number of areas of life and the non-dominant language is only acquired to a limited extent. In particular, the question arises as to whether there has been a shift in dominance between the two languages in favour of High German over the last 2-3 generations of speakers, as the results of recent surveys suggest.

However, these survey results are based on self-reports, which are fundamentally exposed to the risk of being influenced by stereotypes and socio-cultural norms. The research project is looking for new ways of using objective data to gain a more differentiated view of the development of bilingualism in local speaker communities. Following on from research on the relationship between task complexity, cognitive stress and acoustic effects in speaking, the aim is to investigate whether acoustic effects of different stress reactions can also be found in the use of High and Low German. A difference in language proficiency should manifest itself in the fact that the use of the weaker language in complex tasks is associated with increased cognitive stress.

The acoustic effects of cognitive stress are investigated in production experiments in which bilingual speakers of three generations of speakers fulfil speech tasks that differ in their language-specific and general cognitive demand potential. The acoustic analysis includes the measurement of speaking fundamental frequency, voice quality, vowel formants and oral fluency. The study is being carried out in the municipality of Krummhörn in western East Frisia, which is one of the regions with the highest proportion of Low German speakers in northern Germany.

The project aims to make an innovative contribution to identifying different levels of language proficiency among bilingual speakers without having to refer to the achievement of a target linguistic norm. This method seems particularly suitable for assessing the status of regional and minority languages in the context of language mixing and language decline.