The impact of morphological density on reading comprehension in Arabic: A comparison between typically developing and children with reading disabilities

This study examined the influence of morphological density on reading comprehension in Arabic and whether this influence differs between typical and children with reading disabilities. Morphological density in Arabic is a text feature that refers to using bound morphemes, creating dense words with more morphemes. The participants were 182 fifth-graders, both typical and children with reading disabilities. Children were assessed in reading comprehension by reading texts with low- or high-morphological density. Findings revealed that overall morphological density impacted reading comprehension performance. That is, scores were found to be higher while reading low-density text than high-density text. Moreover, an interaction of morphological density condition by reading proficiency showed no density text effect among typical developing readers. However, a difference was obtained in the children with reading disabilities whereas low-morphological density text score was higher than the score of high-morphological density text. The study highlights the importance of morphological awareness in reading comprehension in Arabic, extending that morphological density plays an important role in this process. The results are discussed in light of the lexical quality hypothesis and simple view of reading model. The findings imply the need of explicit morphological instruction for dense morphological forms.