ɫɫ��

Most people tend not to think about their brain regions as they navigate the world, but Ilmoniemi clearly does. It’s humbling when you stop to consider it: all of human experience is mediated by approximately 1300–1400 g of tissue inside our skulls. As you read these words, somewhere at the back of your head, the visual cortex is active, and as you scroll down with a finger or thumb, the motor neurons near the top of your head are firing away.

Ilmoniemi has spent most of his career thinking about this neurological geography. In particular, he’s interested in ways the brain’s operations might be enhanced through technology: fixing glitches, correcting flaws and intervening when it’s failing. 

Ilmoniemi and his colleagues in the ConnectToBrain project — a collaboration between Aalto University, University of Chieti-Pescara in Italy and University of Tübingen in Germany — are world-leaders in the science of transcranial magnetic stimulation (TMS). Using magnetic coils positioned adjacent to the skull, TMS involves non-invasively zapping pulses into the head to induce electric fields within brain tissue that promote or dampen neurological activity. 

When doctors apply these pulses in clinics, TMS can effectively treat pain, severe depression and many other conditions. ‘If you stimulate many times at the same region or same spot, the brain will change,’ says Ilmoniemi. And remarkably, the effect can persist. For many conditions, drug treatment hasn’t worked or is undesirable, so TMS offers a powerful alternative. 

However, TMS is still in its infancy as a treatment. At the moment, the technique requires expert human operators. It’s time-consuming, therefore expensive, and so far the stimulation patterns tend to be relatively simple.

Elsewhere in the hospital, another team uses TMS for alleviating depression – another condition where it can be helpful to offer patients an alternative to drugs. And Vaalto also helps surgeons prepare for operations on brain tumours or epilepsy interventions by identifying areas they need to protect while operating. ‘We can make a map for the neurosurgeons and show them the important areas,’ she says. For example, TMS coils can be used to provoke indicative hand, face or leg twitches in the motor cortex or to identify the most important regions for speech by temporarily preventing people from talking clearly.

However, Vaalto is well aware that these commercial devices are basic compared with prototypes in the laboratory. As a member of the ConnectToBrain team, she works away from the hospital one day each week, helping in the design of the next generation of this technology. 

Multi-coil frontiers 

Most current commercial TMS devices have only one coil within the wand. ‘With commercial devices, you cannot adapt to changes in the brain,’ explains Victor Souza of the ConnectToBrain team. ‘If you want to, let’s say, “play together” with the brainwaves, you cannot, because you need to move – by hand – the stimulator to a different location.’

Souza, Vaalto, Ilmoniemi and their colleagues are working to change this. Their idea? Embed multiple coils of different shapes within the same device: figures of eight, loops and circles, which allow for much more intricate and flexible control. 

They started in 2017 with a simple device that had two coils superimposed over one another.

But more recently their coils have gotten more complex, with the latest device housing five different shapes.

The next step is to build a device that spans across the surface of the skull. ‘We want to expand it to the whole brain. Many brain functions come from the communication of different areas: the frontal part does something, the back of the brain does another thing and so on. So we want to be able to reach all of them fast,’ says Souza. 

Adding robotic control and machine learning algorithms to the mix creates even more possibilities. With all these technologies combined, researchers could identify entirely new ways to stimulate the brain.

Future visions

As the ConnectToBrain team’s multi-coil technology develops, underpinned by artificial intelligence, Ilmoniemi anticipates new avenues for brain stimulation and medical treatment. 

To date, there have been thousands of TMS studies conducted around the world, but almost all have used single coils pointed at single brain regions by a human operator. Ilmoniemi believes that new patterns and sequences could be waiting to be discovered by stimulating the brain at multiple points and using algorithms that can learn. 

But in principle, responding to brain state could go further. Depending on what you're doing, resting or doing motor tasks or using language, the networks will act differently,’ says Ilmoniemi. This raises a hypothesis: if people were encouraged to perform different tasks during TMS sessions – say watching a video, or saying words out loud – would it change the efficacy of the treatment? Scientists don’t yet know for sure, but it’s exciting to contemplate.

Ilmoniemi compares it to playing jazz. It’s about working with the orchestra of the brain: after all, a good musician doesn’t play over the other instruments without listening; they seek to perform in harmony. Thus, when stimulating the brain, algorithms must base their targeting and timing on its rhythms and state.

Beauty in science

Over the course of his career, Ilmoniemi has become fascinated by the possibilities of finding beauty in scientific discovery. Usually, beauty in science is reserved for elegant mathematics or awe-inspiring physics, but the professor also sees it in the brain – and in the technology of TMS.