Impulsivity is one of the core symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD). A recent study published online ahead of print in the journal Brain Stimulation reported on the results of a sham controlled study of the potential benefit of transcranial direct current stimulation (tDCS) for adults with ADHD. The stimulation targeted the dorsolateral prefrontal cortex to promote downstream effects on cognitive control circuits in this region in order to improve impulse control.
Thirty-seven adult participants with ADHD completed two periods of three sessions of either active tDCS or sham. Sessions occurred two weeks apart in a within-subject, double-blind, counterbalanced order. Outcome measures of impulsivity were Conners Continuous Performance Task (CPT) scores and stop signal task (SST) reaction times. Measures were obtained at baseline, at the end of treatment, and 3-day post-stimulation follow-up.
Results indicated a significant stimulation condition-by-session interaction for change in CPT false positives, driven primarily by a reduction of CPT false positives at the end of treatment; this effect did not persist at 3-day follow-up. There was no significant change in CPT false negative errors, hit response time, or SST reaction time. Nonetheless, these preliminary findings suggest a potential therapeutic benefit of tDCS targeting the DLPFC for reducing impulsivity symptoms.
Note: APSARD Board Members Anthony L. Rostain, M.D. and J. Russell Ramsay, Ph.D. are co-authors on this study.
Reference: Allenby C, Falcone M, Bernardo L, Wileyto P, Rostain A, Ramsay JR, Lerman C, Loughead J (2018). Transcranial direct current brain stimulation decreases impulsivity in ADHD, Brain Stimulation, online ahead of print. doi: 10.1016/j.brs.2018.04.016