Verbal working memory in ADHD children

According to neuropsychological models of ADHD, deficits of working memory are regarded as an essential cognitive phenotype for the disorder (Barkley, 1997; Castellanos & Tannock, 2002; Martinussen & Tannock, 2006). The primary goal of the present study was to compare the functioning of the phonological loop and the central executive system in the situation of manipulation of verbal material in children with ADHD (inattentive and mixed subtypes) and without ADHD. 132 children 9-11 years old were examined. Results revealed worse performance of tasks in ADHD children than in healthy children. It may be considered not as a result of difficulties in the performance of operations on verbal material (central executive system) but as a consequence of difficulties in the material maintained in the phonological loop of verbal working memory. There were no differences between mixed ADHD and inattentive ADHD groups.