Investigating the role of verbal and non-verbal working memory measures in complex sentence comprehension by school-aged Greek speaking children

Objectives The present study examines the role of Working Memory (WM), as a cognitive system of limited storage—processing resources, in complex sentence comprehension by typically developing children in both the verbal and non-verbal domain. In particular, the study compares non-verbal and verbal measures of WM in regard to their contribution to complex sentence comprehension. Methods Participants were 169 children aged 8 to 12 years, native speakers of Greek. A self-paced reading task was used to assess the comprehension of syntactically complex sentences. The sentences tested were object-relatives. Non-verbal short-term memory (nvSTM) and non-verbal working memory (nvWM) was measured by corsi blocks forward and corsi blocks backward, respectively. Forward digit span was used for the measurement of verbal short-term memory (vSTM) and backward digit span for the assessment of verbal working memory (vWM). Results Results showed that the only significant predictor of children’s comprehension was backward digit span. Conclusions Findings suggest an important role of vWM in the comprehension of syntactically complex structures, lending support to the view that language comprehension is underpinned by a domain-specific cognitive system specialized to verbal processing.