While it is difficult to associate dyslexia or ADHD to hyperactivity in mice it is tempting to speculate that these species-specific phenotypes may be caused by deficits in neuronal circuitries similarly affected by Nedd4-2 haploinsufficiency and Nedd4-2 heterozygous mice may serve as a model to study these human conditions. The gene discussed is NEDD4L; the disease is attention deficit-hyperactivity disorder.