electrostimulation, a new solution to reach the brain without surgery?

Swiss researchers are working on a project that would make it possible to treat certain illnesses such as obsessive disorders, addictions or even apathy, without resorting to surgery. Explanations.

What if electrical stimulation tomorrow allowed doctors to reach very deep areas of the brain? With a very concrete objective: to treat certain illnesses such as obsessive disorders, addictions or even apathy, without resorting to very invasive surgery on the skull. In Switzerland, a team of neuroscientists at the Ecole Polytechnique (EPFL) in Geneva are working on this project, and have just published their first results on Wednesday May 29 in one of the journals of the prestigious American scientific magazine Nature.

For this study, Pierre Vassiliadis asks volunteers to answer tests, with fictitious rewards at stake. Here, Camilo, a science student, is scrutinized: “We look at how they make decisions based on the effort and the reward we offer“, deciphers Pierre Vassiliadis, before specifying that the “goal of the game“Here is to stimulate the striatum, the part of the brain that involves the reward circuit.

This striatum is located in the center of the skull, between the two ears. However, to achieve it, until now it was necessary to open the brain, with surgery. Here at the Ecole Polytechnique, we are testing electrostimulation in order to achieve it. To do this, the researchers placed four electrodes on our volunteer’s head which send very small electric fields: “I feel a slight vibration on the left side, but it doesn’t hurt…“, reassures Camilo.

“The two pairs of electrodes will create two magnetic fields which will make it possible to target and stimulate only a deep area of ​​the brain, such as the striatum, and not at all the rest of the brain. In fact, it’s like when you throw two stones into water: they will each create a wave. And where the waves meet, it creates interference. Here, we only stimulate the area where these two ‘waves’, these two magnetic fields meet“, deciphers Professor Friedhelm Hummel, who directs this research.

Researchers are, for the moment, only establishing proof of concept. But they hope that by electrically stimulating the striatum, we could in the future treat patients with OCD, learning disorders, addictions or even apathetic patients who lack motivation in their everyday lives. “In the perspective where the patient would come, for example, several times a day for one, two or three weeks for a treatment, we can imagine that by applying this stimulation repeatedly, we will generate plasticity and potentially lead to improvements that might persist after stimulation. That’s what we hope!“, specifies Pierre Vassiliadis.

A second team of researchers, this time from Imperial College London, is working to electrically stimulate the hippocampus in the same way, another deep area of ​​the brain, notably involved in Alzheimer’s disease.