Dr. Onur Özsoy

Bio

I am a linguist specialising in multilingualism, heritage languages, language variation and acquisition, psycholinguistics, grammatical processing, and experimental linguistics.

My research examines how multilingual speakers produce, comprehend, and process language across different linguistic levels, from phonology and morphosyntax to discourse and narrative structure. I use behavioural, eye-tracking, and EEG/ERP methods, alongside corpus analysis and reproducible quantitative workflows in R and Python.

A central strand of my current work investigates code-switching as a natural mode of bilingual language use, including its signalling functions in production and real-time processing. I also work on multilingual language assessment, heritage-language development, individual differences, and collaborative metascience in linguistics.

Current projects

• Code-switching and predictive processing: production and EEG/ERP studies with German–English and Spanish–English bilinguals.
• Code-switching and large language models: comparing human cloze behaviour with model-generated predictions.
• Pronoun resolution in bilingual children: behavioural and eye-tracking work on Turkish–German bilingualism.
• Heritage Turkish morphosyntax: case marking, clause combining, subject realisation, and individual differences in processing.
• Multilingual language assessment: developmental, environmental, and individual predictors of language performance in multilingual children.
• ManyLanguages: collaborative and reproducible approaches to language science.

Publications

In preparation

Mattiauda, E., & Özsoy, O. Narrative macrostructure in English school-aged children in the UK.

Özsoy, O., Vuong, M., Torregrossa, J., & Kaan, E. Signaling functions of code-switching in English–Spanish and English–German bilinguals: Evidence from production and ERP.

Vuong, M., Özsoy, O., & Torregrossa, J. Code-switching in bilingual narratives.

Özsoy, O., Golegos, A., Büyükyıldırım, N., Marinis, T., Schumacher, P., & Torregrossa, J. Pronoun resolution in bilingual Turkish–German children.

Özsoy, O., & Schmidt, A. Variation in language abilities among newly arrived children in the educational system.

Özsoy, O., Iefremenko, K., Büyükyıldırım, N., Schroeder, C., & Gagarina, N. Dynamics of change in accusative and dative realization in heritage and majority Turkishes.

Özsoy, O., & Burbelko, M. “vallah war geschockt” — Topic drop in heritage and monolingual speakers of German.

In press

Oikonomou, D., Miyagawa, S., Özsoy, O., Heycock, C., Vardakis, G., & Bektaş, R. Condition C amelioration effects in wh-movement: An interaction between pronominal type and d-linking. Proceedings of NELS 56.

Fridman, C., Özsoy, O., & Iefremenko, K. Introduction to the special issue: Heritage speakers learning languages: Looking beyond the societal language. Zeitschrift für Sprachwissenschaft.

Chakmakjian, S., & Özsoy, O. Word-final devoicing in Armeno-Turkish.

Faytak, M., Kadavá, Š., Xu, C., Özsoy, O., et al. Big Team Science for language science: Opportunities and challenges. Linguistics. Preprint.

Published

Büyükyıldırım, N., Özceçelik, Ö., Uygun, S., & Özsoy, O. (2025). Individual differences in verb aspect processing in monolinguals and bilingual heritage speakers of Turkish. Journal of Cultural Cognitive Science. DOI.

Özsoy, O., Bauer, E., Bleher, K., Cil, A., Ghaemi, T., Heitzmann, A., Rykova, E., Thillmann, J., Gagarina, N., Grimm, A., Rinker, T., & Scherger, A.-L. (2025). Comprehensive language assessment for multilingual children in Germany. Proceedings of CogSci 2025. Publication.

Özsoy, O., Rizou, V., Martynova, M., Gagarina, N., Szucsich, L., & Alexiadou, A. (2025). Null subjects in heritage Greek, Russian and Turkish. In Linguistic Dynamics in Heritage Speakers (pp. 179–217). Language Science Press. DOI.

Rizou, V., Özsoy, O., Martynova, M., Szucsich, L., Alexiadou, A., & Gagarina, N. (2025). Dynamics of verbal aspect in heritage Greek, Russian and Turkish. In Linguistic Dynamics in Heritage Speakers (pp. 219–249). Language Science Press. DOI.

Rizou, V., Papadopoulou, D., Özsoy, O., & Alexiadou, A. (2025). Novel forms for the expression of aspect in heritage Greek across majority languages. PLOS ONE, 20(5), 1–30. DOI.

Fridman, C., & Özsoy, O. (2024). Sentiments towards heritage languages in research. Heritage Language Journal. DOI.

Martynova, M., Özsoy, O., Rizou, V., Szucsich, L., Gagarina, N., & Alexiadou, A. (2024). Demonstratives in heritage Greek, Russian, and Turkish in Germany and the United States. International Journal of Bilingualism. DOI.

Mattiauda, E., Özsoy, O., Gagarina, N., & Perovic, A. (2024). Inferential abilities in Down syndrome. Proceedings of CogSci 2024. Publication.

Rizou, V., Özsoy, O., Martynova, M., Alexiadou, A., Gagarina, N., & Szucsich, L. (2024). Grammatical aspect in heritage and monolingual Greek, Russian and Turkish. REALIS. DOI.

Özsoy, O., Çiçek, B., Özal, Z., Gagarina, N., & Sekerina, I. (2023). Eye-tracking evidence for Turkish heritage speakers’ predictive use of case-marking in German and Turkish. Frontiers in Psychology, 14. DOI.

Özsoy, O., & Blum, F. (2023). Exploring individual variation in Turkish heritage speakers’ complex linguistic productions: Evidence from discourse markers. Applied Psycholinguistics. DOI.

Özsoy, O., Iefremenko, K., & Schroeder, C. (2022). Shifting clause-combining strategies in heritage Turkishes. Languages, 7(3). DOI.

Oikonomou, D., Rizou, V., Bondarenko, D., Özsoy, O., & Alexiadou, A. (2022). Scalar and counterfactual approximatives: Investigating heritage Greek in the USA and Germany. Languages, 7(1). DOI.

Schäfer, F., Özsoy, O., & Bondarenko, D. (2021). On disjoint reference effects in short passives. Proceedings of WCCFL 39.

Presentations (selected)

Please email me if you would like slides from one of these or another presentation.

Özsoy, O., Vuong, M., Schumacher, P., Torregrossa, J., & Kaan, E. (2026). Signaling functions of code-switching in language: Evidence from production and ERP. AMLaP, Saarland University. Poster.

Özsoy, O., Vuong, M., Torregrossa, J., Kaan, E., Reiter, N., & Liu, Z. (2026). Signaling functions of code-switching: Evidence from human bilinguals and large language models. Multilingual Minds and Machines Meeting, MPI for Psycholinguistics, Nijmegen. Talk.

Özsoy, O., Vuong, M., Torregrossa, J., & Kaan, E. (2026). Signaling functions of code-switching in German–English and Spanish–English bilinguals. Human Sentence Processing, MIT. Poster.

Özsoy, O. (2026). Code-switching as the native mode of early bilingual heritage speakers. Departmental Colloquium, University of Konstanz. Invited talk.

Bektaş, R., Özsoy, O., Oikonomou, D., & Miyagawa, S. (2026). Condition C effects in wh-movement in Turkish: The effect of pronominal type. WAFL 19, Leibniz-ZAS, Berlin. Poster.

Özsoy, O., & Vuong, M. (2026). Code-switching experiments in bilingual narratives. IDeA Data Analysis and Writing Workshop, Frankfurt. Invited talk.

Özsoy, O., Bauer, E., Bleher, K., et al. (2025). Comprehensive language assessment for multilingual children in Germany. CogSci 2025. Poster.

Oikonomou, D., Miyagawa, S., Özsoy, O., Bektaş, R., & Vardakis, G. (2025). Condition C amelioration effects in wh-movement. NELS 56, New York University. Talk.

Özsoy, O., & Chakmakjian, S. (2025). Word-final devoicing in Armeno-Turkish. 22nd International Conference on Turkish Linguistics, İzmir. Talk.

Chakmakjian, S., & Özsoy, O. (2025). Word-final devoicing in Armeno-Turkish cookbooks. University of Vienna. Talk.

Özsoy, O. (2025). Null subjects in heritage speakers in Germany and the United States. University of Siegen. Invited talk.

Özsoy, O., Büyükyıldırım, N., & Özceçelik, Ö. (2024). Proficiency and cognitive skills modulate Turkish monolinguals’ and heritage speakers’ aspect processing and comprehension. AMLaP, University of Edinburgh. Poster.

Özsoy, O. (2024). Proficiency and cognitive skills modulate Turkish monolinguals’ and heritage speakers’ aspect processing and comprehension. University College London. Invited talk.

Teaching

• Summer 2025: Introduction to Linguistics, University of Cologne.
• Summer 2025: German in Multilingual School Contexts, University of Cologne.
• Summer 2025: Heritage Languages in Multilingual Language Acquisition: Theories and Experiments, University of Cologne.
• 2025: Introduction to Statistics with R, SPEAK research consortium.
• 2024: OLIVE-R: Open Linguistic Investigation and Variable Exploration with R, University of Crete.
• 2024: Turkish as a Heritage Language, İstanbul Bilgi University.
• 2024: Theoretical and Empirical Challenges of Multilingual Language Acquisition, Humboldt University of Berlin.
• 2023–2024: Introduction to the Linguistics of Spoken Language, Humboldt University of Berlin.
• 2022–2023: Introduction to the Linguistics of Spoken Language, Humboldt University of Berlin.
• 2023: Eye-Tracking in Language Research, Ghent University.

Academic service and leadership

• Programme Committee, 49th Annual Conference of the German Linguistic Society (DGfS), 2026–2027.
• Executive Board Member, ManyLanguages Consortium, 2025–present.
• Conference co-organiser, ICPL IV, University of Cologne, 2026.
• Ad-hoc reviewer for Journal of Language, Identity & Education, CogSci, Applied Psycholinguistics, Frontiers in Psychology, International Journal of Bilingualism, Languages, and other conferences and journals.
• PhD Representative, Leibniz-Centre General Linguistics, 2022–2024.
• Student representative on the Department Board and Teaching and Learning Committee, Humboldt University of Berlin, 2018–2020.

Scientific outreach

Özsoy, O. (2026). Multilingual development and language assessment for volunteer reading mentors. VBKI Lesepaten, Berlin.

Özsoy, O. (2023). Mehrsprachigkeit — Wie geht das? Workshop series for parents of young children, Kiezoase Schöneberg.

Özsoy, O., Büyükyıldırım, N., Linscheid, P., et al. (2023). Guckst Du noch, oder sprichst du schon? Eye-tracking und Sprachforschung zum Mitmachen. Long Night of the Sciences, Berlin.

Özsoy, O., Marimon, M., & Langus, A. (2023). Eyes as a Window into Language. Berlin Science Week.

Podcast and public engagement

Together with Frederic Blum and Ivona Ilić, I co-created InterFacing Language, a podcast about syntax, semantics, and other areas of linguistics. I was also interviewed for the Leibniz Association’s “Date a Scientist” podcast about multilingual and second language acquisition.

For students and aspiring linguists

First-generation students and students seeking support or academic networking are welcome to contact me. I am happy to discuss possible mentoring programmes, scholarships, and other resources.