A recent meta-analytic review indicates that childhood and adulthood Attention Deficit/Hyperactivity disorder (ADHD: DSM-IV) are characterized by compromised information processing skills including executive function demonstrated in reaction time studies [1]. These cognitive skills are traditionally associated with prefrontal lobe functioning, and indeed, brain mapping studies reported reduced activation in fronto-parietal-cerebral areas (see, e.g., the meta-analysis of Hart and colleagues [2]). Moreover, evidence is growing that cognitive skills including executive function also rely on the cooperation between the two cerebral hemispheres subserved by the corpus callosum [3–5]. This suggests that compromised information processing skills in ADHD may be associated with inefficient interhemispheric communication.