Effects of Motivation and Medication on Electrophysiological Markers of Response Inhibition in Children with ADHD

FROM THE DESK OF MARK MINTZ, MD

An interesting study from Biological Psychiatry on the importance of behavioral approaches to ADHD. Using a “Go/No Go” task, and an electrophysiological parameter (event-related potentials), the authors provided motivational incentives (reward and/or response cost) to children with ADHD known to be medication responsive, and a control group without ADHD. They found that motivational incentives increased amplitudes (for N2 and P3) of event-related potentials correlating to attention (on-task) and response inhibition (restraining impulsive responses) of those with ADHD toward the baseline of the control group. Overall, findings implied that motivational incentives could effect those with ADHD and those without ADHD in a similar manner, and that there were additive effects of these behavioral interventions with stimulant medications.

Groom M, et al. Biological Psychiatry. 2010; 67(7): 624-631. doi:10.1016/j.biopsych.2009.09.029

Similarly, the landmark Multimodal Treatment Study of ADHD (MTA) looked at four approaches to treating ADHD: carefully monitored medication management (stimulant medication), behavior modification (a very intensive approach), combination of behavior therapy and stimulant medication, and routine community care (which included medication). Compared to community care, medication alone or the combination of behavioral and medication therapy were superior to community care or behavioral therapy alone. The combination showed additional benefits compared to medication alone, although modest.

MTA Cooperative Group. National Institute of Mental Health Multimodal Treatment Study of ADHD follow-up: 24-month outcomes of treatment strategies for attention-deficit/hyperactivity disorder. Pediatrics.2004;113:754-761.

Although there cannot be major conclusions from this small study in Bio Psych, it provides reinforcement to the fact that ADHD is a neurobiological disorder, and that adjunctive behavioral strategies are important.

By Mark Mintz