The dancer that the director admired was going to school.
However, RC processing studies in Turkish revealed contrary results, showing easier SRC processing (Bulut et al., 2019; Kahraman, 2015; Kahraman et al., 2010; Özge, 2010). It was also found that participants who learn Turkish as a second language process SRCs easier than ORCs (Altan, 2016; Uzundag & Küntay, 2019). On the other hand, it was claimed that there is no difference between processing SRCs and ORCS if they are given in a context (Boran, 2018). Furthermore, Özge et al. (2015) divided the stimuli sentences into different segments and compared the ORC and SRC reading performances in a self-paced reading test. The authors have reported SRC or ORC processing advantages in different segments of the sentences, but no difference between SRCs and ORCs in total reading times. To the best of our knowledge, RC processing has only been investigated with behavioral metrics in Turkish. Thus, the brain dynamics of RC processing in Turkish remained elusive.
On the other hand, RC processing was investigated with neuroimaging methods in other languages. For instance, a functional magnetic resonance imaging study showed left perisylvian cortex activity during relative clause processing tasks and that processing ORCs was more difficult, even though there were no significant differences in accuracy and reaction time measurements (Caplan et al., 2002). Kovelman, Baker, et al. (2008) have reported that activity in left and right inferior cortices (i.e., Brodmann Area (BA) 44, 45) increases during relative clause processing. Moreover, the authors found that ORC processing is more difficult than SRC processing and caused greater neuronal activity in both left and right inferior cortices, as well as BA 46 and 47 in the right hemisphere, while there was no significant difference in terms of reaction times. Another neuroimaging study showed that processing relative clauses compared to processing unintelligible speech causes an increase in the activity of both left and right dorsolateral prefrontal cortex (DLPFC) (Hassanpour et al., 2015). This study also failed to find a significant difference in terms of behavioural metrics. Lastly, Ding et al. (2021) compared syntax processing in monolingual and bilinguals with different sentence types and found that left DLPFC is amongst the active regions for processing relative clauses and ORCs induced greater neuronal activity than SRCs in both left and right DLPFC.
In summary, neuroimaging studies showed that a robust processing difference between SRCs and ORCs in various languages and that both left and right DLPFC are crucial in RC processing. The findings about the relative processing in Turkish depend solely on behavioural paradigms and are not fully consistent. As stated above, behavioural findings can fail to reveal the processing difficulty differences between SRCs and ORCs. Therefore, we aimed to investigate the prefrontal cortex hemodynamics during relative clause processing in Turkish. We hypothesized that the left DLPFC would be the primary region for neuronal activity since it covers the classical language areas (i.e., Broca’s). Furthermore, we have expected to observe processing difficulty differences between ORCs and SRCs, especially in the lateral parts of the prefrontal cortex.