Neurostimulators, also generally known as brain pacemakers, send electrical impulses to specific areas of the brain via special electrodes. It’s estimated that some 200,000 people worldwide at the moment are benefiting from this technology, including those that suffer from Parkinson’s disease or from pathological muscle spasms. In line with Mehmet Fatih Yanik, Professor of Neurotechnology at ETH Zurich, further research will greatly expand the potential applications: as an alternative of using them exclusively to stimulate the brain, the electrodes will also be used to exactly record brain activity and analyse it for anomalies related to neurological or psychiatric disorders. In a second step, it will be conceivable in future to treat these anomalies and disorders using electrical impulses.
To this end, Yanik and his team have now developed a brand new kind of electrode that allows more detailed and more precise recordings of brain activity over an prolonged time frame. These electrodes are product of bundles of extremely nice and versatile fibres of electrically conductive gold encapsulated in a polymer. Because of a process developed by the ETH Zurich researchers, these bundles will be inserted into the brain very slowly, which is why they don’t cause any detectable damage to brain tissue.
This sets the brand new electrodes other than rival technologies. Of those, perhaps the perfect known in the general public sphere is the one from Neuralink, an Elon Musk company. In all such systems, including Neuralink’s, the electrodes are considerably wider. “The broader the probe, even whether it is flexible, the greater the danger of harm to brain tissue,” Yanik explains. “Our electrodes are so nice that they will be threaded past the long processes that stretch from the nerve cells within the brain. They’re only around as thick because the nerve-cell processes themselves.”
The research team tested the brand new electrodes on the brains of rats using 4 bundles, each made up of 64 fibres. In principle, as Yanik explains, as much as several hundred electrode fibres could possibly be used to research the activity of a fair greater variety of brain cells. Within the study, the electrodes were connected to a small recording device attached to the top of every rat, thereby enabling them to maneuver freely.
No influence on brain activity
Within the experiments, the research team was able to verify that the probes are biocompatible and that they don’t influence brain function. Since the electrodes are very near the nerve cells, the signal quality is superb in comparison with other methods.
At the identical time, the probes are suitable for long-term monitoring activities, with researchers recording signals from the identical cells within the brains of animals for your entire duration of a ten-month experiment. Examinations showed that no brain-tissue damage occurred during this time. An extra advantage is that the bundles can branch out in numerous directions, meaning that they will reach multiple brain areas.
Human testing to start soon
Within the study, the researcher used the brand new electrodes to trace and analyse nerve-cell activity in various areas of the brains of rats over a period of several months. They were capable of determine that nerve cells in numerous regions were “co-activated.” Scientists imagine that this large-scale, synchronous interaction of brain cells plays a key role within the processing of complex information and memory formation. “The technology is of high interest for basic research that investigates these functions and their impairments in neurological and psychiatric disorders,” Yanik explains.
The group has teamed up with fellow researchers on the University College London in an effort to test diagnostic use of the brand new electrodes within the human brain. Specifically, the project involves epilepsy victims who don’t reply to drug therapy. In such cases, neurosurgeons may remove a small a part of the brain where the seizures originate. The thought is to make use of the group’s method to exactly localise the affected area of the brain prior to tissue removal.
Brain-machine interfaces
There are also plans to make use of the brand new electrodes to stimulate brain cells in humans. “This might aid the event of more practical therapies for individuals with neurological and psychiatric disorders,” says Yanik. In disorders reminiscent of depression, schizophrenia or OCD, there is commonly impairments in specific regions of the brain, which results in problems in evaluation of data and decision making. Using the brand new electrodes, it is perhaps possible to detect the pathological signals generated by the neural networks within the brain prematurely, after which stimulate the brain in a way that will alleviate such disorders. Yanik also thinks that this technology may give rise to brain-machine interfaces for individuals with brain injuries. In such cases, the electrodes is perhaps used to read their intentions and thereby, for instance, to manage prosthetics or a voice-output system.
