Abstract/Summary

Data on the typical and impaired acquisition of Arabic is limited and only a few standardized Arabic language assessments are available. As a result, the identification of developmental language disorder (DLD) in Arabic is notoriously challenging. Developing new diagnostic language tools is thus imperative to facilitate early and accurate identification of DLD in Arabic-speaking children with a view to developing relevant interventions. This thesis addressed this issue by investigating potential clinical markers of DLD in Arabic through three theoretically grounded studies focusing on the linguistic and processing deficits that characterize Arabic speaking children with DLD and could be used as indicators of the presence of the disorder. Study 1 showed that the production of verb tense and subject-verb agreement is generally impaired in 5-year-old Arabic-speaking children with DLD relative to same-age peers. Study 1 showed that poor use of present tense and subject-verb feminine agreement could be potential grammatical markers of DLD in Arabic. Study 2 revealed that nonword repetition is an area of difficulty for 4 to 6-year-old Arabic-speaking children with DLD. Importantly, Study 2 found that poor nonword repetition accurately identified 93% of children with DLD and 93% of age-matched TD children, suggesting that poor nonword repetition could also be a possible clinical marker of DLD in Arabic. Study 3 reported poor sentence repetition abilities in 4 to 6- year-old Arabic-speaking children; the sentence repetition task correctly identified more than 90% of children with DLD and more than 90% of age-matched TD children. Study 3 thus suggests that poor sentence repetition may also hold promise as a potential clinical marker for the presence or absence of DLD in Arabic. The findings of this thesis could help enhance the diagnostic practices of DLD in Arabic-speaking children by focusing clinicians’ attention on relevant tasks which could aid diagnosis. The findings extend our understanding of the underlying mechanisms of DLD. Specifically, the language difficulties of Arabic-speaking children with DLD seem to reflect a combination of deficits in linguistic knowledge and processing capacity. This thesis is the first study to my knowledge to address the issue of clinical markers of DLD in Arabic and as such it paves the way and highlights the need for further research to better characterize the linguistic and non-linguistic, as well as the functional limitations in Arabic-speaking children with DLD.