| Author: | Li, Xiaolin |
| Title: | The effectiveness of combining TDCS with cognitive training in children with Attention Deficit Hyperactivity Disorder |
| Advisors: | Han, Yvonne (RS) |
| Degree: | DHSc |
| Year: | 2025 |
| Department: | Faculty of Health and Social Sciences |
| Pages: | vii, 127 pages : color illustrations |
| Language: | English |
| Abstract: | Background: Attention deficit hyperactivity disorder (ADHD) is a chronic neuropsychological condition. The symptoms negatively impact the academic, occupational, and social functioning of school-age children with ADHD, greatly affecting and limiting their development. While there are various therapeutic approaches for managing ADHD, psychostimulants have side effects, and the effectiveness of other interventions is limited. Studies have shown that transcranial direct current stimulation (tDCS) can improve symptoms in ADHD patients, offering a new direction for treatment. The current study explored the potential of combining tDCS with cognitive training (CT) as a more effective intervention. Objective: The purpose of this study is to investigate the effects of tDCS combined with cognitive training on the executive function performance of children with ADHD. Methods: This was a two-armed, randomized, double-blind, controlled clinical trial. Sixty-four children with ADHD were recruited and randomly assigned to two groups. The experimental group received active tDCS combined with cognitive training, while the control group received sham-tDCS with cognitive training. The anode electrode was positioned over the left dorsolateral prefrontal cortex (DLPFC), while the cathode electrode was placed on the right orbitofrontal cortex (OFC). The training sessions lasted 20 minutes each, with 10 sessions conducted over 2 weeks. Outcome measures included the Wisconsin Card Sorting Test (WCST), Continuous Performance Task (CPT), Stroop task, Go/No-Go task, and ADHD Rating Scale-IV (ADHD-RS-IV) scores, assessed at baseline (T0), post-intervention (T1), and 4 weeks after the intervention (T3). Results: A total of sixty-four participants completed the study (22% dropout rate). There was no significant Group × Time interaction for ADHD-RS-IV (or SNAP-IV, where available). On the Go/No-Go task, accuracy showed significant Group × Time interactions (higher Go-correct and No-Go-correct in the tDCS+CT group), whereas reaction time did not. For the CPT, a significant interaction was observed for omission errors only; hit rate, commission errors, and reaction time showed no interactions. All four WCST indices exhibited significant Group × Time interactions favoring the tDCS+CT group (lower overall error percentage, fewer perseverative and non-perseverative errors, and higher correct responses). No significant Group × Time interactions were observed for Stroop accuracy or reaction time. Conclusion: tDCS combined with cognitive training produced selective cognitive benefits, enhanced inhibitory control (Go/No-Go accuracy), reduced CPT omission errors, and improved cognitive flexibility across all WCST indices—without significant advantages on symptom ratings or Stroop performance, and with no effects on reaction-time measures. These findings support domain-specific rather than generalized effects of the combined intervention. Larger, longer trials are needed to confirm durability, examine individual differences in responsiveness, and optimize protocols to target specific cognitive outcomes. |
| Rights: | All rights reserved |
| Access: | restricted access |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| 8656.pdf | For All Users (off-campus access for PolyU Staff & Students only) | 6.29 MB | Adobe PDF | View/Open |
Copyright Undertaking
As a bona fide Library user, I declare that:
- I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
- I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
- I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.
By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.
Please use this identifier to cite or link to this item:
https://theses.lib.polyu.edu.hk/handle/200/14203