According to the CDC, about one in ten (11.4 percent) children are diagnosed with attention deficit hyperactivity disorder (ADHD), millions of whom take prescription medications such as Ritalin and Adderall to treat symptoms such as inattention and impulsivity.
These stimulants are thought to target attention networks, but new research shows that this is not actually the case. According to researchers writing in Cell, instead, the medications target the reward and wakefulness centers of the brain, relieving ADHD symptoms by increasing arousal levels, boosting motivation, and, in some cases, mimicking the power of a good night's sleep.
“Essentially, we found that stimulants pre-reward our brains and allow us to keep working on things that don't normally interest us—like our least favorite class in school,” said Nico W. Dosenbach, the David M. and Tracy S. Holtzman Professor of Neuroscience at Washington University School of Medicine in St. Louis, in statement.
Read more: How People with ADHD Can Use Mind-Wandering and Increase Creativity
Illuminating the reward and arousal centers of the brain
To determine how the brain responds to stimulants, researchers at Washington University School of Medicine in St. Louis compared MRI scans from 5,795 children ages 8 to 11 collected as part of the Adolescent Brain Cognitive Development (ABCD) Study. These included 337 children who took stimulants on the morning of the scan and a further 76 children who had a prescription but did not take the medication that day. The rest were not prescribed stimulants or took them before the scan.
Although the study authors observed few differences between those who took stimulants and those who did not when it came to areas associated with attention (such as the dorsal attention network and prefrontal cortex), there were notable discrepancies in brain regions associated with reward and wakefulness. Instead of improving the brain's ability to concentrate, the drug may work by increasing drive and increasing motivation, the researchers say.
“As a pediatric neurologist, I prescribe many stimulants, and I have always been taught that they facilitate attentional systems by giving people more voluntary control over what they pay attention to,” Benjamin Kay, an assistant professor of neurology at Washington University School of Medicine in St. Louis, said in a statement.
“But we have shown that this is not the case. Rather, the improvement in attention we see is a secondary effect of the child becoming more attentive and finding the task more rewarding, which naturally helps him pay more attention to it,” Kay added.
A follow-up study of five adults without ADHD and without a history of prescription stimulant use seemed to confirm these results. It was the areas of the brain associated with reward and wakefulness that lit up in response to the drug.
Simulate sleep effects
Helpfully, the ABCD study also provides data on scores, sleep patterns, and cognitive test results. They revealed interesting parallels between ADHD medications and sleep.
There were two groups that seemed to benefit from stimulants: those with ADHD and those who slept less than the recommended 9 hours a night. Sleep-deprived children who took medication did better in school than sleep-deprived children who did not, regardless of whether they were diagnosed with ADHD or not. In contrast, the stimulants had no significant effect on neurotypical children who got enough sleep.
The researchers note that medications are not a suitable alternative to sleep and may simply mask certain symptoms (such as inattention) without offsetting the long-term costs of sleep deprivation.
“Lack of sleep is always bad for you, and it's especially bad for children,” Kay said.
At the same time, he urges doctors to consider the amount of sleep a child gets when making a diagnosis. ADHD.
This article does not contain medical advice and should be used for informational purposes only.
Read more: There seems to be more ADHD diagnoses online – is it really that common?
Article sources
Our writers at Discovermagazine.com use peer-reviewed research and high-quality sources for their articles, and our editors review scientific accuracy and editorial standards. Review the sources used below for this article:
