Doctors have relied on the prescription drugs Adderall and Ritalin to treat attention deficit hyperactivity disorder for decades.
More than 15 million American adults and seven million children live with the lifelong condition, which is one of the most common neurodevelopmental disorders in childhood and leaves children unable to focus or control impulsive behavior. About 3.5 million children aged three to 17 take ADHD medicine.
Now, researchers say that stimulants do not work as previously thought.
Instead of affecting the regions of the brain that control attention, the drugs primarily affect the brain’s reward and wakefulness centers, found a recent study by Washington University School of Medicine in St. researchers.
“I prescribe a lot of stimulants as a child neurologist, and I’ve always been taught that they facilitate attentional systems to give people more voluntary control over what they pay attention to,” explained Dr. Benjamin Kay, assistant professor of neurology, in a statement. “But we have shown that is not the case.”
Common medications taken by about 3.5 million American children with ADHD don’t work as well as researchers once thought (AFP/Getty)
“Rather, the improvement we observe in attention is a side effect of a child being more attentive and finding a task more rewarding, which naturally helps them pay more attention to it,” he said.
Instead of improving patients’ ability to focus, the drugs make individuals with ADHD more attentive and interested in subjects they don’t normally enjoy, the study authors said.
The researchers also found that the drugs produced patterns of brain activity that mimicked the effect of good sleep — and negated the effects of sleep deprivation for children with ADHD who didn’t get the recommended nine hours of sleep each night.
And, children on ADHD medication had better academic performance and performed better on cognitive tests.
Researchers used brain imaging data from nearly 6,000 eight- to 11-year-olds collected as part of the Adolescent Cognitive Brain Development Study — the largest long-term study of brain development and child health in the country — to compare the scans and how brain regions communicate in children who took stimulants and children who did not.
Researchers say they are concerned that ADHD stimulant use may mask children’s sleep health problems (Getty Images/iStock)
The researchers then looked at the brains of five healthy adults who did not have ADHD, who took the medication. The results of their observations were the same.
“These results also provide a potential explanation for how stimulants treat hyperactivity, which previously seemed paradoxical,” added Dr. Nico Dosenbach, the David M. & Tracy S. Holtzman Professor of Neurology.
Both researchers said more work is needed to better understand the long-term effects of the drugs on brain function.
Medicines can provide a corrective effect by removing cellular debris in the brain. Or, they can cause lasting damage by covering up chronic sleep disorders.
Previous research has linked ADHD to a lack of proper sleep.
“Sleep disturbances are incredibly common in ADHD, affecting about three out of four children and adolescents with the disorder,” said Jessica Lunsford-Avery, a professor of psychiatry and behavioral sciences at Duke University School of Medicine who was not involved in the study. The Washington Post.
“It is increasingly clear that clinicians and families should consider ADHD as a 24-hour disorder. Unfortunately, sleep problems are rarely recognized or adequately treated in children and adolescents with ADHD.”