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fNIRS Shows that Object Relative Clauses are More Difficult to Process than Subject Relative Clauses in Turkish
  • Murat Can Mutlu,
  • Resit Canbeyli,
  • Hale Saybaşılı
Murat Can Mutlu
Otto von Guericke University

Corresponding Author:[email protected]

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Resit Canbeyli
Bogazici University
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Hale Saybaşılı
Boğaziçi University
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It was suggested that processing subject relative clauses (SRCs) are universally easier than processing object relative clauses (ORCs) based on the studies carried out in head-initial languages such as English, and German. However, studies carried out in head-final languages such as Chinese and Basque refuted this claim. Turkish is also a head-final language. Existing relative clause processing literature in Turkish is based solely on behavioural metrics. Even though an ORC processing disadvantage was suggested for Turkish, the results were not conclusive. Therefore, we aimed to investigate the neural dynamics of relative clause processing in Turkish. We asked 14 native Turkish speakers to answer Yes/No questions about 24 sentences each containing either SRC or ORC while their prefrontal hemodynamic activity was recorded with fNIRS. Our findings revealed hemodynamic activity in the lateral portions of the left prefrontal cortex in both conditions. However, hemodynamic activity was more widespread in prefrontal regions for ORC than SRC. Even though the behavioural metrics failed to produce a significant difference between SRC and ORC conditions, direct ORC>SRC contrast revealed significant activity in left and right DLPFC, which are known to be involved in language processing and conflict monitoring related processes, respectively. Our findings indicate that processing ORCs are more difficult and require further prefrontal resources than processing SRCs in Turkish, thus refuting the head-directionality based explanations of relative clause processing asymmetries.
10 Nov 2022Review(s) Completed, Editorial Evaluation Pending
14 Nov 2022Editorial Decision: Revise Major
21 Jan 20231st Revision Received
22 Jan 2023Assigned to Editor
22 Jan 2023Submission Checks Completed
22 Jan 2023Review(s) Completed, Editorial Evaluation Pending
22 Jan 2023Reviewer(s) Assigned
01 Feb 2023Editorial Decision: Accept