Abstract

We present a study of the linguistic output of the German-speaking writer Robert Walser using Natural Language Processing (NLP). We curated a corpus comprising texts written by Walser during periods of sound health, and writings from the year before his hospitalization, and writings from the first year of his stay in a psychiatric clinic, all likely attributed to schizophrenia. Within this corpus, we identified and analyzed a total of 20 linguistic markers encompassing established metrics for lexical diversity, semantic similarity, and syntactic complexity. Additionally, we explored lesser-known markers such as lexical innovation, concreteness, and imageability. Notably, we introduced two additional markers for phonological similarity for the first time within this context. Our findings reveal significant temporal dynamics in these markers closely associated with Walser’s contemporaneous diagnosis of schizophrenia. Furthermore, we investigated the relationship between these markers, leveraging them for classification of the schizophrenic episode.