TITLE:
Positive Effect of Transcranial Direct Current Stimulation on Visual Verbal Working Memory in Patients with Attention-Deficit/Hyperactivity Disorder
AUTHORS:
Tomoko Uchida, Daisuke Matsuzawa, Tadashi Shiohama, Katsunori Fujii, Akihiro Shiina, Masamitsu Naka, Katsuo Sugita, Eiji Shimizu, Naoki Shimojo, Hiromichi Hamada
KEYWORDS:
Working Memory, Attention-Deficit/Hyperactivity Disorder, Dorsolateral Prefrontal Cortex, Transcranial Direct Current Stimulation
JOURNAL NAME:
Open Journal of Psychiatry,
Vol.14 No.4,
July
19,
2024
ABSTRACT: Background: Working memory is an executive function that plays an important role in many aspects of daily life, and its impairment in patients with attention-deficit/hyperactivity disorder (ADHD) affects quality of life. The dorsolateral prefrontal cortex (DLPFC) has been a good target site for transcranial direct current stimulation (tDCS) due to its intense involvement in working memory. In our 2018 study, tDCS improved visual-verbal working memory in healthy subjects. Objective: This study examines the effects of tDCS on ADHD patients, particularly on verbal working memory. Methods: We conducted an experiment involving verbal working memory of two modalities, visual and auditory, and a sustained attention task that could affect working memory in 9 ADHD patients. Active or sham tDCS was applied to the left DLPFC in a single-blind crossover design. Results: tDCS significantly improved the accuracy of visual-verbal working memory. In contrast, tDCS did not affect auditory-verbal working memory and sustained attention. Conclusion: tDCS to the left DLPFC improved visual-verbal working memory in ADHD patients, with important implications for potential ADHD treatments.