Efficacy and safety of transcranial direct current stimulation over the left dorsolateral prefrontal cortex in children and adolescents with attention-deficit/hyperactivity disorder: a randomized, triple-blinded, sham-controlled, crossover trial

Rachel Silvany Quadros Guimarães; Igor D Bandeira; Bianca Lima Barretto; Thamires Wanke; Clara Oliveira Carvalho Alves; Thiago Lima Barretto; Chrissie Ferreira de Carvalho; Ingrid Dorea-Bandeira; Arthur Tolentino; Daniel H Lins-Silva; Pedro H Lucena; Rita Lucena

doi:10.3389/fpsyt.2023.1217407

Efficacy and safety of transcranial direct current stimulation over the left dorsolateral prefrontal cortex in children and adolescents with attention-deficit/hyperactivity disorder: a randomized, triple-blinded, sham-controlled, crossover trial

Front Psychiatry. 2024 Jan 10:14:1217407. doi: 10.3389/fpsyt.2023.1217407. eCollection 2023.

Affiliations

¹ Programa de Pós-Graduação em Medicina e Saúde, Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil.
² Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, United States.
³ Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil.
⁴ Instituto de Psicologia, Universidade Federal da Bahia, Salvador, Brazil.
⁵ Departamento de Psicologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil.
⁶ Escola Bahiana de Medicina e Saúde Pública, Salvador, Brazil.
⁷ Departamento de Neurociências e Saúde Mental, Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil.

^# Contributed equally.

Abstract

Introduction: Although pharmacological treatment for Attention-Deficit/Hyperactivity Disorder (ADHD) has demonstrated efficacy, several individuals persist in experiencing social and academic impairment. Additionally, the occurrence of significant side effects may render the use of psychotropic medications untenable. However, Transcranial Direct Current Stimulation (tDCS), a non-invasive brain stimulation technique, shows promising results in treating ADHD.

Objectives: To investigate the efficacy and safety of tDCS on the performance of children and adolescents with ADHD in neuropsychological tests involving visual attention, visual and verbal working memory, and inhibitory control.

Methodology: This study was a triple-blind, randomized, sham-controlled, crossover clinical trial. The intervention consisted of a daily session of tDCS (2 mA) or sham targeting the left dorsolateral prefrontal cortex (L-DLPFC), for 30 min, on five consecutive days. The primary outcome was change in the Visual Attention Test, Fourth Edition (TAVIS-4) before and after each intervention. Subjects were also evaluated pre and post-tDCS using the Digit Span subtest of the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V), the Developmental Neuropsychological Assessment, Second Edition (NEPSY-II) Inhibiting Response (IR) subtest, and the Corsi Block-Tapping Task.

Results: Fifteen individuals were included, and no statistically significant difference was observed when comparing the results of the TAVIS-4, the IR of NEPSY-II, and the intragroup Digit Span subtest of WISC-V undertaken before and after the procedure. Adverse events were mainly self-limiting and transient. The participants did not perceive any benefit from tDCS when measured on the Patient Global Impression of Improvement (PGI-I) Scale.

Conclusion: This study did not meet its primary endpoint and found no performance enhancement in any investigated neuropsychological outcomes relating to the intervention group.

Keywords: ADHD; dorsolateral prefrontal cortex; executive functions; neuromodulation; non-invasive brain stimulation; randomized controlled trial; tDCS.