1. Introduction
Syntax processing has been investigated with various paradigms such as center-embedded and left- or right-branching sentences (Inui et al., 1998; Sambin et al., 2012; Santi & Grodzinsky, 2010), in which the modified head comes after or before the modifiers, respectively, and garden-path sentences (Dempsey et al., 2020; den Ouden et al., 2016). Relative clauses (RCs) have also been used in syntax research widely (Cilibrasi et al., 2019; Kovelman, Shalinsky, et al., 2008; Levy et al., 2013). Although there are different ways of classifying the RCs, one classification depends on the function of the modified word in the relative clause. If the modified word is the subject of the relative clause, then it is a subject relative clause (SRC); if it is the object of the relative clause, then it is an object relative clause (ORC). Processing difficulties of ORCs and SRCs have been compared with various methods such as electroencephalography (Bulut et al., 2018; Carreiras et al., 2010), eye-tracking (Sung et al., 2016; Traxler et al., 2002), and functional near-infrared spectroscopy (fNIRS) (Ding et al., 2021). Furthermore, different studies found that SRC processing was easier than ORC processing in different languages such as English (King & Kutas, 1995), German (Schriefers et al., 1995), and Dutch (Mak et al., 2002). Initially, it has been suggested that processing SRCs are universally easier than processing ORCs as these languages differ from each other in various linguistic features such as word order. For instance, the canonical word order in English is Subject-Verb-Object, while in Dutch and German it is Subject-Object-Verb. However, other studies carried out in Mandarin Chinese (Hsiao & MacDonald, 2013; Sung et al., 2016) and Basque (Carreiras et al., 2010) revealed easier ORC processing. Thus, it was claimed that head-directionality could be a significant factor, and SRC processing is easier in head-initial languages, in which the head of the phrase precedes the phrase such as English and German, while ORC processing is easier in head-final languages such as Basque and Mandarin Chinese (Bulut et al., 2018). Turkish is a head-final language with some flexibility (Özge et al., 2015), which implies an ORC processing advantage. In Turkish, relative clauses are prenominal structures (i.e., relative clause precedes the modified word or the head). Subject and object relative clauses are produced by adding different suffixes to the relative clause verb; “-en” for SRC (1) and “-dık” for ORC (2).
(1) Yönetmen-i beğen-en dansçıokul-a gidi-yor-du .
Director -Acc admire-SRC dancer school-Dat go-Prog-Past