The neurobiological origin of attention-deficit disorder (ADD), a syndrome whose causes are poorly understood, has just been confirmed by a study carried out on mice. Researchers have identified a cerebral structure, the superior colliculus, where hyperstimulation causes behavior modifications similar to those of some patients who suffer from ADD. Their work also shows noradrenaline accumulation in the affected area, shedding light on this chemical mediator having a role in attention disorders.