The tricky part is connecting the sticky, thinker brain to a cold, ready-to-scratch computer, getting information through your thick skull – or mine, or anyone else. The entire goal of the skull, after all, is to keep the brain safely separated from it [waves hands at everything].
So if this brain isn’t your brain, the only way to know what’s going on inside it is for inference. People make informed guesses based on what the brain is asking the body to do – for example, if the body makes some sounds that you can understand (that speech) or if it is moving in a way that is recognizable. This is a problem for people trying to understand how the brain works, and it is a bigger problem for people who cannot move or speak due to injury or disease. Advanced imaging techniques such as fMRI can provide you some clues. But it would be nice if you had something more direct. For decades, technologists have been trying to get brains to interact with computer keyboards or robot arms, to get meat to communicate with silicon.
On Wednesday, a team of scientists and engineers demonstrated the results of a promising new approach. It’s common Mounting electrodes On a springy, stretchy tube called a stent, it passes through a blood vessel to the brain. In tests in two people, the researchers literally went into a vein, passed a stent-covered wire into that vein in the throat and then into a vessel near the primary motor cortex of the brain, where they appeared in the spring. The electrodes cuddled into the wall of the vessel and began to sense when people’s brains signaled their intention to move – sending those signals wirelessly to a computer, via an infrared transmitter that’s surgically inserted into people’s chest. in a Article Posted in The Journal of Interventional NeurosurgeryAustralian and American researchers describe how two people paralyzed by ALS (known as Lou Gehrig’s disease) used such a device to send texts and deception over the Internet by controlling the brain alone.
“The self-expanding stent technology has been well proven in cardiac and neurological applications to treat other conditions.“ We are only using this feature and placing electrodes on the stent, ”says Thomas Oxley, an interventional neurologist and CEO of Synchron, which hopes to commercialize the technology. It is fully implantable. Patients go home within two days. It is a “plug and play” feature.
It took practice once the subjects got home. The electrode-studded stent can pick up signals from the brain, but machine learning algorithms have to figure out what those signals represent – the imperfect reflections of the mind at work even under ideal conditions. But after a few weeks of work, patients can use the eye tracker to move the pointer and then click with an idea with the implant. It doesn’t sound like much, but that was enough for both of them to text, shop online, and perform digital daily life activities.
The Food and Drug Administration has not approved what Oxley calls a “stentrode” for widespread use yet, and the company is still chasing funding for further tests, but these preliminary results suggest it’s a working interface between the brain and the computer. The signal he receives is not very informative. Currently, all the captures are one piece of information – either the telepathic mouse click or the absence of that click. But for some applications, this may be enough. “There was a lot of talk about the data and the channels, and what should really be important is, have you introduced a product that changes a patient’s life?” Oxley says. “Just by restoring a few outputs to the patient who controls it, did we get them to take control of Windows 10.”
Lots of more ambitious brain and computer interfaces and neuroprosthetics have appeared in the news recently. Last month, Elon Musk owned Neuralink show up A wireless BCI device with over a thousand flexible electrodes, designed to be inserted directly into the brain by a specialized robotic surgeon. (The company has so far shown only short-term use in pigs.) Insertion of electrodes is difficult; While it is true that brain surgery is not an entirely blatant science, it does have risks whether or not the surgeon is a robot. Even flexible and thin electrodes like the one shown by Neuralink are invasive enough that the brain tries to defend against them, covering them with glial cells that reduce their ability to conduct the electrical impulses they are looking for. And although implanted electrodes such as those in the more common “Utah Array” can obtain clear signals from individual neurons, understanding what these signals mean is still science in progress. Plus, the brain rolls like jelly into a donut. Electrodes held in place may damage it. But if I get it right, they can do a lot more than just brain research. It has been used by “locked up” patients with ALS Successful computer and brain interfaces, Although it does require training, maintenance, surgery, etc.
Meanwhile, electrodes placed directly on the scalp can capture brain waves – an EEG, or EEG – but they lack the spatial detail of the implanted electrodes. Neuroscientists know, roughly, which part of the brain does what it does, but the more you know about the neurons that fire, the better you can tell why they fire.
The latest innovation, electrocorticography, places a network of electrodes directly on the surface of the brain. Combined with intelligent spectral processing of the signals captured by those electrodes, the ECoG is good enough to translate the movement in the part of the motor cortex that controls the lips, jaw and tongue into Text or even speech. There are other methods. CTRL LaboratoriesWhich facebook Buy For up to $ 1 billion in 2019, he’s trying to obtain motor signals from nerve cells in the wrist. nucleus It uses near-infrared spectroscopy of the head to sense brain activity.
If Oxley and co-workers continue to show good results, he will fit somewhere along the spectrum between the implanted electrodes and the EEG. Closer to the first thing than the second, its inventors hoped. But still early days. “The basic technique and the basic idea are pretty cool, but given where they get to the signals, my expectation is that this is a relatively low-resolution signal relative to other brain-machine interface strategies,” says Vikash Jilja, who runs the Transition Neuroscience Lab at UCSAN. Diego. “We know at the very least that a high-density ECG recording from the surface of the brain can convey information beyond what is shown in this paper.”
Possible problem: Tissue conducts electrical impulses, but electrodes in the stent pick up signals from the brain through blood vessel cells. Reduces signal content. “If we take those cortical surface recordings and compare them with the Utah matrix experiments – the bulk of the clinical experience with electrodes implanted – I would say that the ECoG recording method is rate limiting,” says Gilga. (Just for the sake of transparency, I must point out that Gilja has done paid work with BCI companies including Neuralink, which Synchron could theoretically compete with one day.)
So it may not be good enough for neuroscience, but it could be very beneficial for someone with paralysis who wants a low-maintenance BCI that does not require drilling into the skull. “There is a trade-off between how much intervention you want to be and at what level you are gathering information,” says Andrew Pruszynski, a neuroscientist at Western University in Canada. “This is an attempt to reach the middle, to insert a catheter near the nerve activity. It’s obviously invasive, but it’s definitely not as invasive as putting electrodes into the brain.”
There is more work to come. The Oxley team hopes to expand their study to include more human subjects. They will look for possible side effects, such as the chance that a stent may contribute to strokes (although this seems less likely because it integrates into the walls of blood vessels, a process called endometriosis). They may find better stent sites, in blood vessels adjacent to other brain regions of interest. Oxley says anywhere within 2mm of a ship large enough to accommodate the prop is fair game. The software could improve somewhat, in terms of discovering what the brain actually means when it emits its electrical bells and whistles, and some of their tests indicate that the system can pick up more informational details – such as the specific muscles users were trying to contract. This could lead to more beneficial prosthetics or control over devices beyond Windows 10. “The locomotor system, for now, is what will cure people with paralysis,” says Oxley. “But as we start to engage with other areas of the brain, you start to see how technology will unlock the brain’s processing power.” It’s hard to predict what might happen when scientists actually figure out how to get into someone’s head.
This story originally appeared wired.com.