Research Information System
Psychiatry Research, vol.362, 2026 (SCI-Expanded, SSCI, Scopus)
Background and hypothesis: Schizophrenia (SZ) disrupts language in ways that may be universal across languages. This study investigated whether linguistic anomalies previously observed in SZ also occur in Turkish, a morphologically rich and agglutinative language. We hypothesised that SZ patients would differ from healthy controls (HCs) across multiple linguistic domains, including features typically sensitive to cross-linguistic variation. Methods: Speech characteristics of 50 native Turkish-speaking SZ patients were compared with 50 HCs matched for age, sex, length of education, and handedness. Speech data were collected in 15-minute interviews. The interview recordings were transcribed and analysed for various lexical, syntactic, and phonological measures using CLAN, and compared for discourse measures using fastText word embedding models. Results: The number of words produced per minute, mean length of utterance, average word frequency, the number of filled pauses, discourse coherence, and question-response similarity were lower in the patient group than in the control group. The content word-function word ratio, sentence prediction loss, type-token ratio, number of silent pauses, and silent pauses-to-total speech ratio were higher in the patient group than in the control group. Specific clinical and sociodemographic variables were identified as predictors of speech abnormalities in patients. Conclusion: The hypothesis was confirmed. Turkish-speaking SZ patients displayed speech patterns similar to those reported in other language groups, including language-sensitive variables. This supports the idea of universal linguistic disruptions in SZ. The findings are particularly valuable given the scarcity of research on Turkish, a low-resource and typologically distinct language.