Within the world-leading deep brain stimulation program at the Hospital for Sick Children (SickKids), researchers have discovered brain signals that predict when children are likely to lose attention, and that short, targeted interventions in response to those signals can restore focus.
Their research is natural neurosciencethis is the first time this approach to controlling attention has been studied in humans.
Few elements in human experience are more essential than attention. It shapes our perceptions, memories, and interactions, but what happens when it is violated?”
Dr. George Ibrahim, first author, neurosurgeon, and senior research fellow in the Neuroscience and Mental Health Program
Fluctuations in attention are natural, but disruptions in “attentional flexibility” that occur in young people with attention-deficit/hyperactivity disorder (ADHD) can have negative behavioral, psychosocial, and academic consequences. Until now, it was not known exactly how the decline in attention occurs or which neural networks in the brain are involved, so the effects of currently used drugs are limited.
Unique research brings new insights into the brain
The study began with an attentional set-shifting task (measuring how attention shifts between stimuli) in a group of 30 children with epilepsy, which significantly increases the risk of ADHD.
The researchers performed intracranial recordings, where electrodes record directly from deep within the brain, allowing them to monitor neural activity on a millisecond-by-millisecond basis. At the same time, they used a machine learning model to predict fluctuations in attention. This is a world first. Through their model, the researchers pinpointed specific patterns of brain activity that predicted slow or fast attention shifts over several days in all children.
“We were surprised to detect a signature that occurred in the brain just before each child’s attention-shifting delay,” says lead author Nebulas Warsi, Ph.D., a pediatric neurosurgeon and scientist working in Ibrahim’s lab. “By delivering precise electrical stimulation in the moment, each child was able to stay engaged despite the difficult task and complete the task faster and more accurately.”
Children’s performance was monitored through eye tracking, reaction time, and accuracy in detecting attentional lapses during various 20- to 30-minute tasks. Brief electrical stimulation kept their attention only if it was given at a precise moment. When delivered at other times, participants performed worse.
In short, timing was everything.
Expand the scope to other children
Could we expect the same results in other children without epilepsy? To find out, the researchers used non-invasive magnetoencephalography imaging on 37 typically developing children and 25 children with ADHD.
By targeting the same signals in the brain, researchers were once again able to predict delayed attention. We then used non-invasive transcranial magnetic stimulation electroencephalography (TMS-EEG) and found that reaction time and accuracy were significantly improved when a single pulse was delivered to the target area. This time we use a simple EEG cap and TMS coil, and no intracranial brain electrodes are required.
This suggests long-term potential for non-invasive tools that can support attention when it’s needed most.
Although these technologies are still in their infancy, Ibrahim said they open up promising new directions that can advance precision child health at SickKids and around the world by understanding attention challenges and supporting each child in a personalized way.
“A lot of people study neurological and neuropsychiatric disorders in adults, but very few go into pediatrics,” says Professor Ibrahim, who is also the Abe Bresver Professor of Functional Neurosurgery. “We need to ethically advance possible treatments for children and young people, and to do that we need to understand neural circuits.
“The potential to change the lives of so many children is so important.”
This research was supported by the Canadian Institutes of Health Research (CIHR), Brain Canada through the Azrieli Future Leaders in Canada Brain Research Award, and Abe Bresver, Professor of Functional Neurosurgery at SickKids. Dr. Warsi is supported by a CIHR Vanier Fellowship, a James and Mari Rutka Surgeon-Scientist Award, and an Edward Christie Stevens Fellowship in Medicine.
sauce:
hospital for sick children
Reference magazines:
Warsi, New Mexico, others. (2026). Closed-loop stimulation modulates children’s attentional shifts. natural neuroscience. DOI: 10.1038/s41593-026-02294-0. https://www.nature.com/articles/s41593-026-02294-0
