Executive Functions and Self-Regulation Among Children With and Without ADHD in Germany and Taiwan

For a deeper understanding of the mechanism underlying the effects of MPH and implementation intentions, neurophysiological data (with a special interest on the P300 component) during a Go/NoGo task will be assessed additionally to the behavioral performance (i.e., response times and error rates). Meanwhile, the information may contribute to a better understanding of a potential influence of culture on the effect of implementation intentions. The effect may be equally effective in the cultures, but the underlying processes might still differ. On the other hand, differences between the two cultural groups might be explained by different neurophysiological activity during the tasks.

Two primary research questions arise: (1) Are MPH and implementation intentions (i.e., if-then plans) effective in enhancing the performance of executive function tasks measured by the Go/NoGo task in children and adolescents with ADHD compared with those without ADHD within each culture? (2) Does culture play a role in moderating the effect of implementation intentions on executive function tasks in children and adolescents with ADHD, respectively? Based on the research questions, two hypotheses are formulated. First, after the treatment of MPH and the self-regulation strategy of forming implementation intentions, it would result in less inhibition errors and more increased amplitudes of NoGo P300 and NoGominusGo P300 in children and adolescents with ADHD. Second, participants with ADHD in Taiwan may benefit more from the self-regulation strategy, which is reflected in more increased amplitudes of NoGo P300 and NoGominusGo P300 than found in their counterparts in Germany. However, since this is the first study to compare the effects of forming implementation intentions in a cross-cultural way, this latter analysis is more exploratory.

Inclusion criteria

• Participants with ADHD have to meet the criteria of ICD-10 (WHO, 1991) before enrolment.
• Participants with ADHD are diagnosed with ADHD combined subtype.
• Ages range from 10 to 14 when we conduct the study.
• IQ full score ≥ 80.

Exclusion criteria

• The subjects will be excluded from the study if they currently meet criteria or have a history of the following condition as defined by DSM-IV: Schizophrenia, Schizoaffective Disorder, Organic Psychosis, Mental Retardation, or Pervasive Developmental Disorder. Moreover, the subjects will be excluded from the control group if have a history of the following condition as defined by DSM-IV: ADHD or ASD in addition to the above exclusion criteria.