Transcranial direct current stimulation effects in inhibitory control in individuals with attention deficit/hyperactivity disorder (P6.218)

Objective: To investigate the efficacy of transcranial direct current stimulation (tDCS) on the modulation of inhibitory control in adults with attention deficit/hyperactivity disorder (ADHD). Background: One of the most common executive functions affected in ADHD is inhibitory control. Therapeutic approaches directed towards enhancing behavioral inhibition and improving other cognitive symptoms remain a challenge in ADHD. tDCS has emerged as a promising tool in modulating spontaneous neural network excitability. The possibility of being able to modify prefrontal and striatal circuits may result in an improvement in executive functions and raises its potential as a therapeutic approach for ADHD. Design/Methods: A parallel, randomized, double blind, and sham-controlled study was conducted to assess the efficacy of tDCS on the modulation of inhibitory control in adults with ADHD. Sixty patients performed go/no go tasks before and after either anodal tDCS (1mA, 35cm 2 , 20 minutes) over the left dorsolateral prefrontal cortex or sham stimulation, according to the group they were assigned to by block randomization. Results: Analyses of the effects resulting from the stimulation procedure revealed no significant differences between the two groups (tDCS vs. sham) with regard to changes in the scores with respect to the correct responses (letters: t(58):−0.28, p:0.78; fruits: t(58):0.40, p:0.69), impulsivity (letters: U:0.41, p:0.68; fruits: U:0.02, p:0.98) or omission errors (letters: t(58):−0.27, p:0.79; fruits: t(58):−0.14, p:0.89) for either of the two tasks. Conclusions: The present results revealed that one single tDCS session at 1 mA exerted no significant effect on behavioral performance in ADHD patients. Taking into account that ADHD is a chronic neurodevelopmental disorder with reduced brain activation in prefrontal regions, possibly a single session of stimulation may not have been enough to improve cognitive performance in this population. For future trials, significant results may be achieved with an increased number of intervention sessions. Study Supported by: N/A Disclosure: Dr. Cosmo has nothing to disclose. Dr. Baptista has nothing to disclose. Dr. Nogueira de Araujo has nothing to disclose. Dr. do Rosario has nothing to disclose. Dr. Garcia Vivas Miranda has nothing to disclose. Dr. Camprodon has nothing to disclose. Dr. Montoya has nothing to disclose. Dr. Ponde de Sena has nothing to disclose.