The brain's dopamine system, which has long been associated with reward learning and reward-related behavior, works differently in treated and untreated attention deficit hyperactivity disorder (ADHD) individuals, according to a study presented by German researchers at SNM's 53rd Annual Meeting in San Diego.
"The significant difference we found between treated and untreated ADHD patients provides an important hint on the effect of the most commonly prescribed drug for this disease, which has long baffled and frustrated parents and physicians," noted Felix M Mottaghy, research fellow at University Ulm in Germany. Until this study, there has been no direct evidence pointing to the beneficial effect of methylphenidate (drugs like Ritalin) on the body's dopamine system, added the co-author of "Midbrain, Striatal and Amygdalar Dopaminergic Dysfunction in Attention Deficit Hyperactivity Disorder (ADHD)." For years, researchers have speculated that methylphenidate calms people with ADHD by amplifying the release of the neurotransmitter dopamine, improving attention and focus in those who have weak dopamine signals. "This is a very preliminary basic science study, initiated by Andrea G. Ludolph from the child and youth psychiatry department of the University Ulm; however, future studies of the dopamine system could aid differential diagnosis in hyperactive children," said Mottaghy.