New Study Fills In Critical Gaps In Understanding Of How Stimulants Work To Treat ADHD

Science Daily reports on a new study from the University at Buffalo, published in the Journal of Child Psychology and Psychiatry, and how its findings are filling in critical gaps in the understanding of how prescription stimulant medications such as methylphenidate (MPH) reduce ADHD symptoms and improve behavior.

The article notes that stimulants are responsible for improving a number of cognitive processes.

“In the case of stimulant treatment of ADHD, improved classroom behavior and seatwork completion are well-documented clinical benefits. There’s also laboratory evidence that stimulants improve a wide range of cognitive processes, including working memory (holding and manipulating information in your mind), the ability to inhibit (such as remembering to raise your hand rather than shout out an answer) and sustained attention (staying on task for long periods of time) key problem areas for many school-aged children with ADHD…”

During the course of the study, led by Larry Hawk from the University at Buffalo, the 82 children in the study, ages nine to 12, received either a dose of stimulant medication in the low to moderate range or a placebo. The children were then instructed to complete a series of activities such as spots, crafts, and math classes designed to assess their cognitive abilities.

Researchers observed how each child responded to medication on cognitive tests in relation to how much their classroom behavior and how many math problems they solved to find out how much the medication accounted for the result. Hawk spoke on the importance of the data collected, saying that their findings are the strongest yet to suggest by which mechanisms stimulant medications are working.

“The results provide the strongest evidence to date that stimulants like methylphenidate improve classroom behavior and performance by enhancing specific cognitive processes. Specifically, the more medication helped kids hold and manipulate information in working memory (like being able to remember things in reverse order) and the more it helped children inhibit responses ‘on the fly’, the greater the classroom benefit.”

Researchers often explain the efficacy of certain medications with a good hypothesis, said Hawk, but how or why many work to treat certain conditions continues to remain a mystery. Knowing the how and the why of an effective treatment, Hawk added, can help researchers shave necessary years off of the number of 15 to 20 years it takes for a new medication to be approved for use by the general public.

“I hope that we and others are now able to take those next steps and turn these novel findings into even more practical outcomes for families.”