News of the WeekNeurobiology

How Stimulant Drugs May Calm Hyperactivity

See allHide authors and affiliations

Science  15 Jan 1999:
Vol. 283, Issue 5400, pp. 306
DOI: 10.1126/science.283.5400.306

You are currently viewing the summary.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution


On page 397, a team of neurobiologists reports a surprising explanation for the paradoxical effectiveness of prescribing psychostimulant drugs to calm children with attention-deficit hyperactivity disorder (ADHD): Low doses may raise concentrations of the neurotransmitter serotonin, which is known to have calming effects. The researchers gave psychostimulant drugs, including methylphenidate (Ritalin), to mice that were genetically altered to have behavioral symptoms similar to those of hyperactive children and found that the mice's symptoms were relieved. Compounds that boost serotonin in the brain were found to have similar effects, a result suggesting that this neurotransmitter, rather than dopamine, as has been believed, is instead the one that tones down the animals' hyperactivity. Many ADHD researchers are not convinced that the mouse results apply to human patients. But if humans do respond in the same way as the mice, researchers might be able to design new ADHD therapies that work by mimicking serotonin's effects.