January 5, 2025 – A new study has identified a distinctive pattern of brain activity in children with attention-deficit/hyperactivity disorder (ADHD) and demonstrated that it may be modified using an intervention combining non-invasive brain stimulation and cognitive training. 

The research, published in NeuroImage: Clinical, focuses on a subtle but powerful feature of brain signals measured by EEG, known as aperiodic activity, irregular, non-rhythmic background “noise” or scale-free fluctuations in brain signals. Unlike traditional EEG markers, which often produce mixed or inconsistent results in ADHD, this neural signature reliably distinguished children with ADHD from their typically developing peers. 

The study was led by Hebrew University of Jerusalem researchers (HU) Dr. Ornella Dakwar-Kawar and Prof. Mor Nahum in the School of Occupational Therapy and Prof. Itai Berger from the HU Faculty of Health Sciences. 

“ADHD is highly heterogeneous, and many of the neural markers we’ve relied on until now don’t consistently capture that complexity,” the researchers said, “Our findings suggest that aperiodic brain activity may offer a more sensitive window into how the ADHD brain functions.” 

Children with ADHD may exhibit a distinctive, measurable pattern of brain activity that could reflect differences in neural efficiency. The researchers focus on aperiodic EEG activity, proposing it as a potentially more consistent marker than some commonly used EEG measures. They also report that, in this study, the pattern shifted in a more typical direction following a combined intervention involving non-invasive brain stimulation and cognitive training, with changes observed even after the program ended.  

The study followed children aged 6–12, comparing behavioral performance and brain activity during attention and inhibition tasks. Children with ADHD showed elevated aperiodic EEG activity, a pattern associated with reduced neural efficiency. 

In the second phase, a subgroup of children with ADHD participated in a randomized, sham-controlled trial combining cognitive training with transcranial random noise stimulation (tRNS), a painless, non-invasive form of electrical brain stimulation. The researchers targeted frontal brain regions involved in attention and self-control. 

After ten sessions, children who received active stimulation showed a significant reduction in the atypical brain signal, along with improvements in task performance. Importantly, some of the neural effects persisted 3 weeks after the intervention ended. 

“This is not just about improving behavior in the moment,” the researchers explained. “We’re seeing changes in underlying brain dynamics that appear to move closer to typical developmental patterns.” 

ADHD is currently diagnosed and monitored primarily through behavioral reports, which can be subjective and variable. The identification of a robust, biologically grounded neural marker could help advance more precise assessment tools and guide future interventions. 

The study also strengthens the scientific basis for non-pharmacological treatments, which are increasingly sought by families and clinicians. 

“Medication remains effective for many children, but it’s not the only path,” the researchers said. “Our results suggest that targeted brain-based interventions may help rebalance neural activity in ways we can now measure objectively.” 

While the researchers emphasize that larger and longer-term studies are needed, they see this work as an important step toward personalized, mechanism-driven approaches to ADHD. 

The research paper titled “The effects of transcranial random noise stimulation on excitation/inhibition balance in ADHD” is now available in NeuroImage: Clinical and can be accessed here.

Researchers:

Dakwar-Kawar Ornellaa, Jude Ashwin Amalb, Arya Renub, Mairon Noama, Mishra Jyotic, Berger Itaid, Cohen Kadosh Roie, Balasubramani Pragathi Priyadharsinib, Nahum Mora

Institutions:

  1. School of Occupational Therapy, Hebrew University of Jerusalem, Israel
  2. Department of Cognitive Science, Indian Institute of Technology Kanpur, Kanpur 208016, India
  3. Department of Psychiatry, University of California San Diego, USA
  4. Pediatric Neurology Unit, Assuta-Ashdod University Hospital and Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
  5. School of Psychology, University of Surrey, Guildford, UK