Cross-linguistic differences in categorical perception: Comparison of Danish and Norwegian

Are all languages processed in the same way, or might typological variation cause systematic differences between languages? We explore this question through a cross-linguistic comparison of categorical perception in two closely related languages, Danish and Norwegian. We employ drift diffusion models to reveal cross-linguistic differences in the role of context: Danish – a more phonologically-opaque language – shows equally strong context effects of both near and distal context, while Norwegian shows stronger context effect of near than distal context. We argue that the difference is due to a processing strategy: due to the more transparent sound structure of their language, Norwegians pay more attention to local acoustic information - while Danes, due to the opaque phonology of Danish, seem to use later-occurring contextual information to a larger extent. Indeed, when forcing participants to delay their decision until the full information is available, Norwegians show choice patterns more similar to those of Danes. Our findings highlight the importance of cross-linguistic studies, as even closely related languages like Danish and Norwegian, appear to be processed differently contingent on individual properties of the specific language.