Abstract One of the central assumptions in Cognitive Linguistics is that the cognitive mechanisms underlying our language use are domain-general and thus apply to human behavior beyond language. Examples of such cognitive mechanisms are, among others, our ability to focus attention, to memorize and categorize, as well as processes related to chunking, generalization, and inhibitory control. Testing this core assumption, however, is often difficult, as it requires us to move beyond linguistic research and to actively look for links between our language use and other areas of human cognition. This paper is an illustration of what such links could look like, particularly focusing on links between research on (Dutch-German) language contact and expert behavior. In doing so, it shows (a) that there are many shared links, for example, regarding the cognitive mechanisms of entrenchment and chunking, and (b) that these shared links (as well as potential differences across the fields) can be used to improve our linguistic theorizing. In particular, I argue that linguistic research can benefit from the insights from research on expert behavior, especially from its more advanced insights modelling individual variation, and that the shared links can help us to test the core assumption that the cognitive mechanisms underlying our language use are indeed domain-general.