Working Memory Training in Young ADHD Children

Inclusion Criteria: * Age between 4 years/6 months and 7 years/4 months * Diagnosis ADHD, classified by the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 2000) * A full scale IQ \>= 80 * Psychopharmaca- naïve or -free * Access to a PC with Windows Vista or Windows XP with internet connection and speakers at home Exclusion Criteria: * Currently intensive (i.e. weekly) individual or group psychotherapy * Regular use of medication * Diagnosis of one or more of the following comorbid psychiatric disorders: Major depression, Bipolar disorder, Psychotic disorder, Chronically motor tic disorder or Gilles de la Tourette, Conduct disorder, any other autism spectrum disorder except for Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS), Eating disorders, Anxiety disorders * Neurological disorders (e.g. epilepsy) currently or in the past * Cardiovascular disease currently or in the past * Serious motor or perceptual handicap * Participation in another clinical trial simultaneously * Educational level and/ or socio-economic situation that makes it unlikely for the family to fulfil this study