Worlds shaped by words: A cross-linguistic investigation into the neural mechanisms of lexico-syntactic feature production.

The dissertation Worlds shaped by words. A cross-linguistic investigation into the neural mechanisms of lexico-syntactic feature production examines the neurocognitive mechanisms underlying the processing of lexico-syntactic features during language production. The work focuses on two widespread yet typologically distinct nominal classification systems: grammatical gender in German and classifier systems in Mandarin Chinese. In addition, the dissertation addresses the processing of such features in second language acquisition and in non-canonical lexical categories. The thesis is guided by four central research questions. First, it investigates whether and how classifiers are activated during Mandarin noun phrase production. Second, it examines the extent to which semantic properties of classifiers—particularly visual shape features—are involved in this process. Third, it explores whether late learners of German with Mandarin as their first language can process grammatical gender, despite the absence of this feature in their L1. Fourth, the dissertation assesses whether semi-lexical nouns activate lexico-syntactic features in the same way as prototypical content words. To address these questions, the author reports a series of experimental studies combining established psycholinguistic paradigms, such as the Picture–Word Interference paradigm and the Blocked Cyclic Naming paradigm, with behavioural measures and electrophysiological recordings (EEG). Across studies, the results consistently show that classifiers in Mandarin are activated during speech production and that their processing involves semantic features such as visual shape. These effects are reflected not only in naming latencies but also in electrophysiological markers, including N400 effects associated with semantic processing. The studies on second language production demonstrate that Mandarin-speaking learners of German exhibit neural signatures of grammatical gender processing, even though grammatical gender is absent in their native language. This finding suggests that adult L2 learners can acquire and process novel functional features at the neural level, albeit potentially with reduced automaticity compared to native speakers. Furthermore, the investigation of semi-lexical nouns reveals that these items can engage lexico-syntactic feature activation despite their reduced semantic content, supporting the view that lexical categories form a continuum rather than a strict dichotomy between content and function words. Overall, the dissertation makes a substantial contribution to psycholinguistic and neurolinguistic research by demonstrating that lexico-syntactic feature processing is supported by shared cognitive mechanisms across languages, while at the same time being strongly modulated by semantic transparency, language-specific structures, and language learning experience. By integrating behavioural and electrophysiological evidence within a cross-linguistic framework, the work extends existing models of language production and provides a nuanced account of how linguistic systems shape cognitive and neural processes.