Cover story

A novel brain scanning technology that has created ‘neural fingerprints’ could enable early diagnosis of neurodegenerative conditions such as dementia. Stephanie Price speaks to Professor Matthew Brooks, chairman of Cerca Magnetics, which has developed the technology, to find out more.

A spinout from the University of Nottingham, Cerca Magnetics has developed a lightweight, wearable Cerca scanner - known as OPM-MEG - that utilises quantum technology.

The scanner tracks brain function and how it changes over time to support cognition. 

In a new study, the device successfully identified individuals through their unique brain pattern activity, and Brooks explains that this development has the potential to transform diagnosis of conditions such as dementia and Alzheimer’s Disease.

The scanner uses sensors called optically pumped magnetometers (OPMs) that exploit the quantum properties of atoms to measure minute magnetic fields generated by the millions of brain cells that coordinate brain activity.

Can you explain what neural fingerprints are in simple terms?

The scanner measures magnetic fields that are generated above the scalp by current flowing in neurons. Those currents actually constitute your brain activity. 

It turns out that your brain activity is unique to you - if we both measured our brain activity today and then we measured it tomorrow, we'd be able to tell who's who by just looking at the brain activity. 

Your brain activity is your own fingerprint - it's your neural print. That's where this terminology comes from. 

Listen to our interview with Professor Matthew Brooks on the NR Times podcast below:

By detecting these magnetic fields, and from that, inferring our brain activity, we are getting information about something that's unique to you.

The scanner uses something called optically pumped magnetometers and taps into quantum physics. Can you explain, for people who aren't familiar with quantum physics, how the device works and how it detects those neural fingerprints?

An Optically pumped magnetometer or an OPM, is called quantum technology because it uses the fundamental principles of quantum mechanics. In simple terms, that means it uses atoms to measure things in the real world that we wouldn't normally be able to see. 

For instance, a magnetic field is invisible - you can't see it, but by using a set of atoms and preparing them in a certain way, these invisible things suddenly become visible. 

In an OPM, you have a little gas cell, and that gas cell is full of, in our case, rubidium atoms. You can essentially talk to those rubidium atoms by shining light on them. 

If you get light of a specific frequency and you shine it onto those atoms, then those atoms will change their properties. They'll change their energy levels, and they'll change their angular momentum. You can also change the magnetic properties of that gas of atoms. 

You pump these atoms into a specific state where all of their little magnetic moments align with each other, and in that way, the gas of atoms, because of this alignment, becomes magnetic. 

If it senses a second magnetic field, like the one from our brains, then it changes its behaviour, and we can detect that. It's in that way that we can measure these very, very small magnetic fields from the brain.

Can you tell us about that and what you found in your own research so far, and the impact that the scanner can have to change healthcare?

We're particularly focused on dementia, but also conditions like epilepsy, multiple sclerosis, and Parkinson’s disease. The technology has potential applications across a wide range of neurological disorders.

One key indicator we look for is something called cortical slowing. When dementia begins to develop, there’s a noticeable shift in brain activity. The brain's electrical activity is made up of patterns known as neural oscillations, or more commonly, brain waves.

In healthy adults, these brain waves have a balance between high and low frequencies. But in people with early dementia, we see an abnormal increase in low-frequency activity and a decrease in high-frequency activity, essentially, the brain is “slowing down.”

Interestingly, this pattern is also seen in children, who naturally have more low-frequency brain activity. So, we’re trying to detect this slowing as early as possible.

If we can spot those early changes, we might be able to screen for dementia before symptoms become obvious. That opens up opportunities for earlier diagnosis, the ability to tailor treatment plans to the individual, and importantly, track the efficacy of treatments, whether it's medication or behavioural therapy.

By objectively measuring these brain signals, we can monitor whether someone is actually improving or not, which is incredibly valuable for both patients and clinicians.

How does this compare to traditional tools like MRI or EEG?

Traditional tools like MRI are excellent for structural imaging, they show you what the brain looks like. But with conditions like dementia or epilepsy, especially in early stages, the brain might look completely normal on an MRI.

With EEG, which has been around for over 100 years, you can measure brain function by placing electrodes on the scalp. But EEG has three major limitations.

It’s slow to set up, as you have to attach each electrode to make proper contact with the scalp, and the electrical signals have to pass through the skull, which distorts them and reduces spatial accuracy.

EEG is also highly susceptible to interference from other electrical activity, like muscle movements, which can obscure the signals from the brain.

Our system uses magnetoencephalography, or MEG, which detects the magnetic fields generated by brain activity. These fields aren’t distorted by the skull, so we get millimeter-level spatial resolution, we can see exactly where in the brain things are happening.

Because our scanner is wearable and quick to set up, we can start scanning within a minute of someone walking in. It’s also much less affected by movement or muscle artifacts, which is a big deal, especially for patients who struggle to stay still.

One unique aspect of this brain scanner is its mobility, people can move during a scan. Why is that such a major advancement over traditional devices?

Most brain imaging devices require the person to stay completely still, which is hard for anyone, but it’s especially difficult for children or people with neurological conditions. 

For example, with MRI, if you're scanning a child, they often have to be sedated just to stay still. But the issue there is: if you're sedated, you're no longer seeing normal brain function.

Our goal is to measure brain function in natural situations, not lying still in a tube. Think about people with Parkinson’s disease, where movement itself is impaired. We want to understand what the brain is doing as they move - walking, standing, turning - not just sitting still. That's what this wearable scanner enables us to do.

With older technologies like EEG, you could try to measure during movement, but the results get very noisy. EEG picks up a lot of muscle artifacts and has poor spatial resolution. Our system avoids those limitations. 

We’ve now scanned Parkinson’s patients while walking or turning, the very actions they struggle with, to see how their brain is behaving during those moments.

What inspired the development of this technology?

It all started about 10 years ago, during the launch of the UK’s National Quantum Technology Programme. There was a push to develop devices called atomic magnetometers - small, ultra-sensitive sensors capable of detecting magnetic fields more accurately than anything we’d seen before.

A US company called QuSpin built the first commercially available OPM. We were fortunate enough to get one of the very first units and used it to measure magnetic signals from the human brain. At that time, we could only scan a tiny region of the brain.

Over time, we scaled up, from a 13-sensor setup to eventually building a 50-channel wearable system, and now a full 384-channel head scanner. 

It’s been a decade-long journey from early simulations to a functioning, commercialised brain scanner.

What’s next? Where do you see this technology going in the future?

The next big step is clinical application, starting with epilepsy. Around a third of epilepsy patients have seizures that aren’t well controlled with medication. Some of them are candidates for surgery, but the challenge is pinpointing exactly where in the brain the seizures start.

This technology can do that with high precision, but we need medical device approval before it can be widely used, whether that's through the FDA, UK MHRA, or EU regulatory routes. Once that happens, it unlocks real-world clinical use.

From there, the potential expands to conditions like dementia, Parkinson’s, and, in the future, even harder-to-diagnose conditions like schizophrenia and depression. Those are much more complex, but we’re beginning to identify biomarkers that could help.

In short, we’re just scratching the surface. This technology opens the door to personalised treatments, better tracking of brain health, and possibly even early interventions, long before symptoms emerge.

Any final thoughts for people interested in brain science or working on similar innovations?

Keep going. The brain is still one of the biggest scientific mysteries we face - especially as the global population ages. Disorders like dementia will only become more common, and we desperately need more tools to understand, diagnose, and treat these conditions.

This technology is just one piece of the puzzle, but it’s an exciting one, and there’s still so much more to discover.