Cognitive training for children with ADHD: Individual differences in training and transfer gains

The aim of this dissertation was to determine the efficacy of cognitive training for school-aged children with Attention-Deficit/Hyperactivity Disorder. We were mainly interested in whether the effects of training would generalize to functioning in everyday life, especially in terms of classroom behavior and academic performance. By means of a randomized controlled trial we investigated the effects of Cogmed Working Memory Training (CWMT) and a new, classroom embedded, cognitive training called ‘Paying Attention in Class’ (PAC) which contained a working memory and a compensatory executive function training. Children in both treatment groups improved on the short and long-term on multiple neurocognitive outcome measures. These results were supported by improvements found on parent and teachers executive functioning and ADHD related behavior ratings. Children did not improve on measures of academic performance, behavior in class and quality of life. Given the clinical and pathophysiological heterogeneity of ADHD, the other chapters in this thesis focused on the individual differences in treatment outcomes. It was found that several clinical and baseline neurocognitive variables influenced the treatment outcome measures, indicating that cognitive training might be more beneficial for certain subgroups. We suggest that cognitive training should be viewed as an adjunctive treatment of current guidelines, bearing in mind that it is not an one size fits all treatment. Although future research still faces many theoretical and methodological challenges before cognitive training meets the criteria as an evidence-based treatment for ADHD, this dissertation has highlighted the need to assess training and transfer gains on a more individual level.