Taken together with the genetic association of the 7-repeat (7R) variant of the human DRD4 gene with increased risk for attention deficit hyperactivity disorder (ADHD) and altered gamma-band responses (Demiralp et al., 2007; Gizer et al., 2009), these findings should renew interest in the D4R and its possible contribution to synchronization of PFC networks during cognitive tasks. This evidence concerns the gene DRD4 and attention deficit-hyperactivity disorder.