Children with attention-deficit/hyperactivity disorder, or ADHD, notoriously fidget in the classroom. That disruptive behavior likely isn't just a symptom, but may actually boost cognitive performance, a new study finds.
Physical activity, like bouncing on a ball chair or even chewing gum, seems to allow these children to focus on difficult tasks, according to research from the University of California Davis MIND Institute, published Thursday in the online journal Child Neuropsychology.
"It's not anything conscious, but you see children use hyperactivity to boost their attention," said study co-author Julie Schweitzer, professor of psychiatry and behavioral sciences and head of the UC Davis ADHD Program.
"They go up and down the room, and jump on chairs and dive under the tables when something is very demanding or boring," she told NBC News. "When they are concentrating hard, their tongues are moving. There is always movement."
In the study, researchers did a trial-by-trial analysis of 26 teens and pre-teens diagnosed with ADHD and a control group of 18 with typical development, looking at how the intensity and frequency of movement affected their ability to do tests that demanded focus.
The children's movement was measured by a device attached to their ankles as they did a "flanker test." The test required them to pay attention to the direction of a series of arrows and to disregard distractions.
The ADHD students with the highest number of correct answers, showed the greatest degree of movement. There was no correlation between movement and cognition in children without the disorder.
Researchers say that children with ADHD are unable to modulate their arousal systems efficiently, and movement helps them compensate for that deficit.
"Sometimes they are over-aroused by irrelevant information and at other times, they are under-aroused," said Schweitzer.
About 11 percent of all children between the ages of 4 and 17 have ADHD, making it difficult for them to pay attention and control impulsive behavior, according to the Centers of Disease Control and Prevention.
Sherri Charlton, a 38-year-old mother from Westchester County, New York, said her 8-year-old son's hyperactivity has improved with both medication and a school that accommodates his need to move.
"Jack really struggled in pre-school," she told NBC News. "During circle time on the carpet, he just couldn't not touch the kid beside him, and poke their feet and lay on them and bug them."
Today, his teacher encourages him to chew gum, which helps Jack's concentration, and academically, he is thriving.
"He also has a 'silly band' wrapped on the bottom of his chair to bounce his legs on," said Charlton. "Something about keeping part of his body busy, helps keep him focused."
Dr. Dale Archer, a psychiatrist and founder of The Institute for Neuropsychiatry in Lake Charles, Louisiana, said the MIND Institute study corroborates what doctors have known anecdotally.
"Some schools have exercise as a key component of the curriculum," he told NBC News. "They have chin-up bars in the hallway and some have student do laps from building to building."
Archer, author of the book, "The ADHD Advantage: What You Thought Was a Diagnosis Could be Your Greatest Strength," said both he and his son have the disorder.
"I was always sent to the principal's office for being disruptive in class," said Archer. "I was smart, but I didn't pay attention."
He watched the same behavior in his son Trey, but discovered that movement helped, so much so, that the boy never needed medication.
"Gym class was his savior," said Archer. "After lunch and PE, the rest of the afternoon was fine."
Trey Archer, now 30 and living in China, has successfully used his ADHD to travel the world, teaching English. He said the study made sense.
"Everybody is different and all minds think differently, so why not?" he wrote in an email to NBC News. "The classroom would be more productive if they allowed students to learn the way they wanted to."
Study author Schweitzer said teachers should find ways to incorporate movement in class to help children with ADHD leverage their cognitive potential without disrupting other students.
"If a child is sleepy and having a hard time concentrating, take a walk," she said. "Don't have them go on the iPad and Google something. Do something physical for a short period of time and come back. That will help them."