This article was originally published in the Spring 2026 Print edition.
Researchers from King’s College London (KCL) have published new research into the treatment for attention deficit hyperactivity disorder (ADHD).
ADHD causes difficulties with concentration, impulsivity, and hyperactivity. It affects around three million people in the UK. ADHD is generally managed through lifestyle changes, talking therapies and medication.
For many children with ADHD, school becomes increasingly difficult to manage. ADHD medication can cause side effects like insomnia, headaches and appetite loss, making parents apprehensive. Thus, there is a growing need for different kinds of ADHD treatment.
Brain stimulation devices are a potential solution gaining increasing popularity. These are non-invasive with minimal side effects. One brain stimulation device is trigeminal nerve stimulation (TNS). The TNS device is worn on the head while asleep. It provides gentle electrical pulses to stimulate brain regions involved in attention and self-control.
A study by researchers at University of California, Los Angeles (UCLA) investigated TNS in children with ADHD, finding it effective in reducing ADHD symptoms. However, the study contained a major limitation – the children in the control group received no stimulation at all. This poses a risk for the placebo effect. As the children could easily tell whether or not they were receiving the treatment, the mere belief and expectation in the success of the treatment may have reduced ADHD symptoms.
Even so, the US Food and Drug Administration (FDA) approved TNS as a viable treatment option, allowing it to enter the private clinic market in the UK, at a significant cost to families affected by ADHD. But, the National Institute for Health and Care Excellence (NICE) in the UK has yet to approve the treatment in the NHS, citing a lack of strong evidence in favour of it.
Researchers under Professor Katya Rubia at KCL addressed these limitations by conducting a study on 150 children with ADHD, including a group that wore devices that looked like and provided stimulation similar to TNS devices. This ensured expectations would not influence results. Findings showed that although TNS was safe, it was not effective in reducing symptoms of ADHD.
Such research highlights the need for multiple, rigorous tests of novel treatment methods, ensuring effective solutions. This will also help counter the replication crisis, wherein many findings across science, especially in psychology, tend not to replicate.
Even though TNS might not be effective in reducing symptoms of ADHD, it sheds a light on possible avenues to investigate safe and successful treatments.