Attention deficit hyperactivity disorder, better known as ADHD, is a neurodevelopmental disorder that’s usually diagnosed during childhood and can last into adulthood. Though millions of Americans are diagnosed with the disorder, scientists disagree about its characteristics, outcomes, and causes. Naturally, misdiagnosis is a major concern — especially because it makes it easier to access Adderall, a common medication for ADHD that’s also a popular recreational drug.

On Wednesday, however, scientists publishing a paper in the journal Radiology make the case that they have an objective way to diagnose ADHD: brain scans.

Brain scans taken using magnetic resonance imaging (MRI), the West China Hospital at Sichuan University scientists write, can improve the accuracy of ADHD diagnosis, which in turn will speed up the process identifying and treating them. In their study, they were able to identify ADHD patients using MRIs with 74 percent accuracy as well as tell the difference between inattentive ADHD and other subtypes of the disorder with 80 percent accuracy.

In addition to treating ADHD, Adderall is also a popular recreational drug.

If MRIs do become the standard of diagnosing ADHD, it has the potential to change the way Adderall is circulated among people who don’t have ADHD. Research has shown that millions of American adults who don’t have ADHD but want to use the drug as a stimulant are prescribed Adderall annually. A 2014 study, published by the American Academy of Pediatrics, showed that out of 815 doctors, 59 percent believed their patients were using their Adderall for something besides ADHD, whether that be partying, working, or studying.

Using any medication for off-label uses is, of course, generally unsafe. While Adderall can help treat ADHD’s symptoms of inattention, hyperactivity, and impulsive behavior, its effects can be dangerous for people without the disorder. The number of young adults who had to go to the emergency room because of Adderall-related reasons rose by 156 percent between 2006 and 2011.

MRIs can measure how brains are different.

In the new study, led by Qiyong Gong, M.D., Ph.D., 83 children between the ages of 7 and 14 received an MRI. These children were all newly diagnosed with ADHD and had never been treated. For comparison, the researchers also took MRIs of a group of 87 children who did not have ADHD. The MRIs use had a new feature, which the study authors say allowed them to examine for more than 3,100 features of the brain.

They didn’t see any differences in the total brain volume and total gray and white matter volumes between the two groups, but they did find alterations in the shape of three brain regions of people with ADHD: the temporal lobe, bilateral cuneus, and the areas around the left central sulcus. They also found that the children with ADHD had different patterns of activity in their default mode network, the regions of the brain that are active when a person is not engaged in a task, and in their insular cortex, which is linked to self-control.

“The results of this study provide preliminary evidence that cerebral morphometric alterations can allow discrimination between patients with ADHD and control subjects, and also between the most common ADHD subtypes,” the researchers write.

“By identifying features relevant for diagnosis and subtyping, these findings may advance the understanding of neurodevelopmental alterations related to ADHD.”