Imaging the developing brain using light at the Pears Maudsley Centre

Brain imaging has revolutionised how we understand mental health in children and young people. It reveals that these conditions have real biological foundations and that every child’s brain is unique. Brain scans also allow us to explore how children and young people develop, and what happens in the brain when development takes an unexpected turn for example, when a child or a young person experiences a mental health condition like anxiety or depression or has a developmental condition like attention deficit hyperactivity disorder (ADHD). 

Can we really study the brain using light?   

One particularly exciting way to study the brain is by using light. While it may sound like something from a science-fiction film, the way it works is probably more familiar to you than it might at first seem. In the same way that a fitness watch uses light to measure heart rate, scientists can use light to measure brain activity. This method is called functional near-infrared spectroscopy, or fNIRS. It allows us to observe how the brain functions while children take part in everyday activities, rather than only when they are lying still in a scanner. 

How does this light-based brain imaging actually work?  

Children simply wear a soft, comfortable hat (a bit like a swimming cap) with small sensors that shine harmless near-infrared light onto the head.  

Our brains need oxygen to do its work. Whenever we do something, like listening to music or solving a puzzle, certain brain regions work harder than others and then and use more oxygen than others. The body responds by increasing blood flow to those areas of the brain. Blood that carries a lot of oxygen absorbs light differently from blood with less oxygen and the fNIRS hat picks up on these subtle changes to map brain activity. By measuring how much of the light travels through the head and is absorbed at any given time, scientists can see which areas of the brain are active and how that activity shifts over time. 

Why can fNIRS be such a game-changer for studying the brain during development? 

fNIRS is one of the newest, most flexible brain-imaging tools available. Unlike many traditional brain-imaging methods, fNIRS is quiet, non-invasive and highly flexible. MRI scanners, for example, have greatly advanced our understanding of the (developing) brain, but they require people to lie still inside a noisy, enclosed space. This can be challenging or overwhelming for many children and young people, especially very young children, children with different sensory needs or those with neurodevelopmental conditions like ADHD. fNIRS lets children move more freely and behave more naturally. This opens the door to research that is more inclusive, allowing more children to participate in science studies.  This movement-friendly design also makes fNIRS very valuable for understanding behaviour in real-world situations. Researchers can observe children while they chat with their parents, explore toys, solve age-appropriate tasks or even play together. Or we can study two young people wearing fNIRS hats at the same time, allowing us to understand how the developing brain works in real-life communication. This kind of natural, real-time data is extremely difficult to gather using traditional brain imaging method.

How will fNIRS help us improve mental health care for young people?  

We are already using fNIRS in our research within the King’s Maudsley Partnership and will continue to grow its use when the Pears Maudsley Centre for Children and Young People opens next year. Enabling children who would have otherwise been excluded from participating in research to take part is central to ensuring our work will be more likely to benefit all children, not just the easiest to study. fNIRS is an example of how we are centering inclusion and equity in our research. 

Once our understanding of the developing brain in the real-world has improved we can then work as the King’s Maudsley Partnership, on bringing it into therapeutic settings / the clinic.  

We hope that fNIRS will become a key tool for advancing our mission to improve mental health care. For example, by helping us design interventions that are tailored to an individual child or young person’s specific strengths and challenges. Or by helping clinicians with choosing the most effective treatment plan, so that we can get care and support to families faster and more efficiently. 

We also hope that brain imaging studies can then not only take place in the dedicated clinical research facilities but also in school or community settings, and even in the comfort of your homes. Our goal is to make science work for and with every child and young person, so that they can thrive to the best of their ability.  

If you want to learn more about fNIRs and our work in this area please contact us on KMPCYP@slam.nhs.uk. Learn more about the Pears Maudsley Centre.

Learn more about Dr Louisa Gosse and her work.