An RCT into the effects of neurofeedback, methylphenidate and physical activity on ERPs in children with ADHD

Objective: EEG neurofeedback is considered a non-pharmacological alternative for medication in attention-deficit/hyperactivity disorder (ADHD). Comparisons of the behavioral efficacy of neurofeedback and medication have produced inconsistent results. EEG measures can provide insight into treatment mechanisms, but have received little consideration. In this randomized controlled trial (RCT), effects of neurofeedback (NF) were compared with methylphenidate (MPH), and physical activity (PA) in children with ADHD on event-related potential (ERP) indices of response inhibition, which are involved in ADHD psychopathology. Methods: Using a multicenter three-way parallel group RCT design, 112 children with a DSM-IV diagnosis of ADHD, aged between 7-13 years, were initially included. NF training consisted of 30 sessions theta/beta training at Cz over a 10-week period. PA training was a semi-active control group, matched in frequency and duration. Methylphenidate was titrated using a double-blind placebo controlled procedure in 6 weeks, followed by a stable dose for 4 weeks. ERP measures of response inhibition, N2 and P3, were available for 81 children at preand post-intervention (n=32 NF, n=25 MPH, n=24 PA). Results: Only the medication group showed a specific increase in P3 amplitude compared to neurofeedback (ηp2=.121) and physical activity (ηp2=.283), which was related to improved response inhibition. Source localization of medication effects on P3 amplitude indicated increased activation primarily in thalamic and striatal nuclei. Conclusions: This is the first study that simultaneously compared neurofeedback with stimulant treatment and a semi-active control group. Only stimulant treatment demonstrated specific improvements in brain function related to response inhibition. These results are in line with recent doubts on the efficacy and specificity of neurofeedback as treatment for ADHD. Neural mechanisms of treatment in ADHD: ERPs