Comparing the Comprehension of Complex Relative Clauses in Dyslexic and Normal Persian Children

This study investigated and compared the comprehension of subject-subject (S-S) and subject-object (S-O) relative clauses in dyslexic and normal children. Three types of errors were analyzed. Since there is no available study on comprehension of relative clauses bydyslexic Persian children, the present research is a pioneering work in this field. This study adopted a cross-sectional, descriptive, and comparative design.In order to evaluate the comprehension of relative clauses, a multiple-choice pictorial test with four alternatives was designed. The test was administered to 30 third to fifth grade elementary dyslexic students and 30 normal ones. One of the alternatives was the correct response and the other three were distracters which contained main clause error (MCE), relative clause error (RCE), and double clause error (DCE). Datawere analyzed by Mann-Whitney U and Chi-squared tests. Results demonstrated significant differences between dyslexic and normal children in the comprehension of both types of relative clauses (p ≤0/0001). Dyslexic children performed weaker than normal children in the two kinds of relative clauses, and in their group, the percentage of all three types of errors was higher. Dyslexicand normal children had lower comprehension ofS-O relative clauses and the complexity of S-O relative clauses was confirmed on the basis ofdependence locality theory, structural distance hypothesis, linear distance hypothesis, and word order difference hypothesis. Accordingto obtained results, it was indicated that compared to normal children, in what cases the dyslexic children had more problems and in which syntactic structures they needed to have more practice.

Extended Abstract
In the past thirty years, processing relative clauses in different languages has had an important role in linguistic and psycholinguistic researches. A common theme in experimental studies has been the comparison of performance on subject and object relative clauses. Moreover, the comparison of verbal abilities in normal and dyslexic children is one of the most important issues in the interdisciplinary field of psycholinguistics. Evidence shows that dyslexic children not only have poor phonological processing, but also show compromised performance in complex syntactic processing tests as compared with normal children. This study investigated and compared the comprehension of subject-subject (S-S) and subject-object (S-O) relative clauses in children with dyslexia and normal children. The Present study tested the predictions of three hypotheses and one theory including dependence locality theory, structural hypothesis, linear hypothesis and word order difference hypothesis. This study had a cross sectional, descriptive and comparative design. The study population consisted of third to fifth grade elementary students in Kerman in 2017-2018 academic year. Participants were 60 monolingual Persian-speaking students (mean age of 10.5 years): 30 with developmental dyslexia and 30 normal children. Dyslexic children were selected by availability sampling and normal children were selected by table of random numbers. These students were evaluated by vocabulary pre-test and grammar pre-test. Two pre-tests measured comprehension of words and transitive verbs.  In order to evaluate comprehending of two types of relative clauses, a picture-matching test with four alternatives was designed. One of the alternatives was the correct response and the other three contained main clause error (MCE), relative clause error (RCE), and double clause error (DCE). The error category was designed to provide insight into misinterpretations. The first category was MCE where only the subject-verb relation in the embedded verb was interpreted correctly. The second error category was RCE, where only the subject relation in the main clause was interpreted correctly. The last category was DCE, where both subject-verb relations were erroneously interpreted. The test was designed by considering the viewpoints of experts in the Persian language. After preliminary analysis and eliminating inappropriate items, the final test was designed with eight items, which measured comprehension of S-S and S-O relative clauses. Reliability of this test was assessed by Pearson correlation coefficient. Pearson coefficient of 0.96 was obtained. The test was conducted to compare each group's performance on each relative clause type. The children were tested in a quiet room individually. They were told to read out a sentence that matched only one of the pictures and their task was to choose the picture that the sentence had described. Preliminary instructions emphasized the importance of looking carefully at all pictures and being accurate rather than fast. Children's responses were scored according to one of the four categories. One was target response and the remaining responses were errors. At the end, data was gathered from two groups and three types of errors were analyzed. Afterwards, data were analyzed by Mann-Whitney U and Chi-squared tests. Results demonstrated significant differences between dyslexic and normal groups in the comprehension of both types of relative clauses (p≤0/0001). Dyslexic children performed weaker than normal children in two types of relative clauses, and the percentage of all three types of errors was higher in them. Moreover, children with developmental dyslexia encountered more difficulties in the comprehension of S-O relative clauses, and the percentage of all three types of errors increased in them. Children with developmental dyslexia and normal children fail to comprehend only one part of relative clauses. In S-S and S-O relative clauses, the most common error related to MCE, indicating that children cannot comprehend the relationship between subjects and verbs in main clauses. In both relative clauses, the least common error related to DCE, indicating that children cannot comprehend only one part of the relative clause. The percentage of all errors in S-O relative clauses was higher in both groups. Furthermore, S-O relative clauses were more difficult tocomprehended than S-S relative clauses, which confirmed structural distance hypothesis, dependence locality theory, linear distance hypothesis and word order difference hypothesis. The noted problems may be eliminated with further and earlier training for children with developmental dyslexia. Obtained findings from this study propose that in addition to phonological awareness, the syntactic ability of Persian-speaking dyslexic children needs to be improved. Due to the intrinsic limitation of our behavioral method, it is clear that more investigation, especially brain imagining, is warranted in order to characterize the nature of the deficit in dyslexic children more specifically.