Meta's Breakthrough: Wristband Technology for Mind-Controlled Computing

Control your computer with your mind? Meta's working on that

Since the onset of the command line, the way humans have interacted with their computers has been restricted to a keyboard. Meta's new wristband seeks to change that. Last week, Reality Labs at Meta, the team responsible for developing the company's AR and VR offerings, published a paper in Nature detailing plans for a noninvasive wristband that uses electrical signals from the user's body for human-computer interactions. The wristband, meant to be wireless and comfortable, allows users to navigate the world around them in different neuromotor ways. These include 1D continuous navigation, similar to pointing a laser pointer based on their wrist posture; gesture detection, such as finger pinches; and handwriting recognition options, which allow users to draw using gestures with their neuromuscular signals, according to the paper. Also: Can Amazon finally make AI wearables happen? This buzzy new device could be its best bet Unlike other gesture-based tech, these gestures aren't read by a camera system or other sensors. Rather, it predicts the user's intent from their neuromuscular signals using a measure of muscle activation via electrical signals sent from their brain when they make certain movements. This process is known as surface electromyography (sEMG), and is also used for prosthetic control. Meta VP of research Thomas Reardon told The New York Times that with practice, just the intent of moving is enough to produce the motion necessary to make the action happen on the computer. ZDNET's Managing Reviews Editor Kerry Wan has tested many XR/VR headsets and finds that the type of wristband Meta is working on would move the space forward significantly. "A wristband accessory capable of processing muscle movement at such a granular level would greatly enhance VR/XR applications," said Wan. "These include more commercial use cases like gaming and interacting with virtual characters online, but they also expand to professional work like graphics design and content creation." Other companies are developing similar products to remove friction between users and their devices. For example, the Mudra Link is a neural wristband that leverages proprietary sensors and AI algorithms to allow users to interact with their devices hands-free. I demoed the Mudra Link at CES, and it was easy to use and a fun change of pace from touching a screen or typing into a keyboard. This seamless interaction between users and their devices is especially welcomed in VR/XR applications, where an obstacle to comfortable use is getting the hang of the gestures or the handheld controls. Beyond these uses, it could also offer new opportunities for a wider audience with greater accessibility. "We've seen an uptick in digital input accessories for VR, like the Logitech MX Ink, but to be able to make precise actions with just your fingers is the most natural, frictionless next step -- especially from an accessibility standpoint," added Wan. Meta has yet to announce an official release date.

Want to control your computer with your mind? Meta's working on that

Since the onset of the command line, the way humans have interacted with their computers has been restricted to a keyboard. Meta's new wristband seeks to change that. Last week, Reality Labs at Meta, the team responsible for developing the company's AR and VR offerings, published a paper in Nature detailing plans for a noninvasive wristband that uses electrical signals from the user's body for human-computer interactions. The wristband, meant to be wireless and comfortable, allows users to navigate the world around them in different neuromotor ways. These include 1D continuous navigation, similar to pointing a laser pointer based on their wrist posture; gesture detection, such as finger pinches; and handwriting recognition options, which allow users to draw using gestures with their neuromuscular signals, according to the paper. Also: Can Amazon finally make AI wearables happen? This buzzy new device could be its best bet Unlike other gesture-based tech, these gestures aren't read by a camera system or other sensors. Rather, it predicts the user's intent from their neuromuscular signals using a measure of muscle activation via electrical signals sent from their brain when they make certain movements. This process is known as surface electromyography (sEMG), and is also used for prosthetic control. Meta VP of research Thomas Reardon told The New York Times that with practice, just the intent of moving is enough to produce the motion necessary to make the action happen on the computer. ZDNET's Managing Reviews Editor Kerry Wan has tested many XR/VR headsets and finds that the type of wristband Meta is working on would move the space forward significantly. "A wristband accessory capable of processing muscle movement at such a granular level would greatly enhance VR/XR applications," said Wan. "These include more commercial use cases like gaming and interacting with virtual characters online, but they also expand to professional work like graphics design and content creation." Other companies are developing similar products to remove friction between users and their devices. For example, the Mudra Link is a neural wristband that leverages proprietary sensors and AI algorithms to allow users to interact with their devices hands-free. I demoed the Mudra Link at CES, and it was easy to use and a fun change of pace from touching a screen or typing into a keyboard. This seamless interaction between users and their devices is especially welcomed in VR/XR applications, where an obstacle to comfortable use is getting the hang of the gestures or the handheld controls. Beyond these uses, it could also offer new opportunities for a wider audience with greater accessibility. "We've seen an uptick in digital input accessories for VR, like the Logitech MX Ink, but to be able to make precise actions with just your fingers is the most natural, frictionless next step -- especially from an accessibility standpoint," added Wan. Meta has yet to announce an official release date.

Meta builds wristband that can control devices with a flick of the...

Forward-looking: A new chapter in human-computer interaction is unfolding at Meta, where researchers are exploring how the muscles in our arms could soon take the place of traditional keyboards, mice, and touchscreens. At their Reality Labs division, scientists have developed an experimental wristband that reads the electrical signals produced when a person intends to move their fingers. This allows users to control digital devices using only subtle hand and wrist gestures. This technology draws on the field of electromyography, or EMG, which measures muscle activity by detecting the electrical signals generated as the brain sends commands to muscle fibers. Typically, these signals have been used in medical settings, chiefly for enabling amputees to control prosthetic limbs. Meta's work, however, rekindles decades-old ideas by leveraging artificial intelligence to make EMG an intuitive interface for everyday computing. "You don't have to actually move," Thomas Reardon, Meta's vice president of research heading the project, says. "You just have to intend the move." Since experiments began, the prototype wristband has evolved beyond clunky early visions. Now, by detecting faint electrical pulses before any visible movement, the device allows actions like moving a laptop cursor, opening apps, or even writing in the air and seeing the text appear instantly on a screen. "You don't have to actually move," Thomas Reardon, Meta's vice president of research heading the project, told The New York Times. "You just have to intend the move." This distinction - where intent is enough to trigger action - a leap forward that could outpace the very fingers and hands we've long relied upon. A hardware and software platform for high-throughput recording and real-time decoding of sEMG at the wrist. Unlike some emerging neurotechnology approaches, Meta's solution is entirely noninvasive. Efforts by startups like Neuralink and Synchron are focused on brain-implanted or vascular devices to read thoughts directly, complicating adoption and raising risks. Meta sidesteps surgery: anyone can fasten this wristband and begin using it, thanks to advanced AI models trained on the muscle signals of thousands of volunteers. "The breakthrough here is that Meta has used artificial intelligence to analyze very large amounts of data, from thousands of individuals, and make this technology robust. It now performs at a level it has never reached before," Dario Farina, a bioengineering professor at Imperial College, London, who has tested the system, told The New York Times. With EMG data from 10,000 people, Meta engineered deep learning models capable of decoding intentions and gestures without user-specific training. Patrick Kaifosh, director of research science at Reality Labs and a co-founder of Ctrl Labs, which was acquired by Meta in 2019, explained that "out of the box, it can work with a new user it has never seen data for." The same AI foundations that support this wristband also drive progress in handwriting recognition and gesture control, freeing users from physical keyboards and screens. Reardon credits years of steady research, starting at Ctrl Labs, for bringing the technology to its current level. "We can see the electrical signal before your finger even moves," he said. "We can listen to a single neuron. We are working at the atomic level of the nervous system," he said. Beyond serving able-bodied users, the technology shows promise for those with limited mobility. At Carnegie Mellon University, researchers are already evaluating the wristband with people who have spinal cord injuries, allowing them to operate computers and smartphones despite impaired hand function. The system's ability to pick up faint traces of intention - sometimes before any visible movement - brings hope to those who have lost traditional motor abilities. "We can see their intention to type," said Douglas Weber, professor of mechanical engineering and neuroscience at Carnegie Mellon. Meta aims to fold this technology into consumer products in the coming years, envisioning an era when everyday tasks - from typing to sending messages - are performed invisibly, with the flick of a muscle or the mere intent to act. The company's recent study published in Nature reports that with continued AI personalization, accuracy in decoding gestures can exceed that of previous approaches, even keeping up with rapid muscle commands. The research also described a public dataset containing over 100 hours of EMG recordings, inviting the scientific community to build on their findings and accelerate progress in neuromotor interfaces. Reardon, widely recognized as the architect of Internet Explorer, now sees the challenge as making "technology robust and available to everyone." He adds: "It feels like the device is reading your mind, but it is not. It is just translating your intention. It sees what you are about to do." Permalink to story:

Meta Unveils Wristband For Controlling Computers With Hand Gestures

When you write your name in the air, you can see the letters appear on your smartphone. The prototype looks like a giant rectangular wristwatch. But it doesn't tell the time: It lets you control a computer from across the room simply by moving your hand. With a gentle turn of the wrist, you can push a cursor across your laptop screen. If you tap your thumb against your forefinger, you can open an app on your desktop computer. And when you write your name in the air, as if you were holding a pencil, the letters will appear on your smartphone. Designed by researchers at Meta, the tech giant that owns Facebook, Instagram and WhatsApp, this experimental technology reads the electrical signals that pulse through your muscles when you move your fingers. These signals, generated by commands sent from your brain, can reveal what you are about to do even before you do it, as the company detailed in a research paper published on Wednesday in the journal Nature. With a little practice, you can even move your laptop cursor simply by producing the right thought. "You don't have to actually move," Thomas Reardon, the Meta vice president of research who leads the project, said in an interview. "You just have to intend the move." Meta's wristband is part of a sweeping effort to develop technologies that let wearers control their personal devices without touching them. The aim is to provide simpler, quicker and less awkward ways of interacting with everything from laptops to smartphones -- and maybe even to develop new digital devices that replace what we all use today. Most of these technologies are years away from widespread use. They typically involve tiny devices surgically implanted in the body, which is a complicated and risky endeavor. These implants are tested solely with disabled people who cannot move their arms and hands, and need new ways of using computers or smartphones. Neuralink, a Silicon Valley start-up founded by Elon Musk, aims to implant chips under the skull, beside the brain. Synchron, run by an Australian neurologist, hopes to implant devices inside blood vessels in the neck. These efforts, like those of many other start-ups, aim to read brain activity directly -- an enormously complex process that must be tailored to the individual. Meta is taking a simpler approach. Its technology does not require surgery. Anyone can strap on the device and start using it. Using artificial intelligence techniques, Dr. Reardon and his team have identified common electrical signals that appear when a person moves a finger, wrist or thumb. "This idea -- this kind of technology -- is not new, it is decades old," said Dario Farina, a professor of bioengineering at Imperial College, London, who has tested the technology but was not involved in the research. "The breakthrough here is that Meta has used artificial intelligence to analyze very large amounts of data, from thousands of individuals, and make this technology robust. It now performs at a level it has never reached before." Meta's wristband uses a technique called electromyography, or EMG, to gather electrical signals from muscles in the forearm. These signals are produced by neurons in the spinal cord -- called alpha motor neurons -- that connect to individual muscle fibers. Because these neurons connect directly to the muscle fibers, the electrical signals are particularly strong -- so strong that they can be read from outside the skin. The signal also moves much faster than the muscles. If a device like Meta's wristband can read the signals, it can type much faster than your fingers. "We can see the electrical signal before you finger even moves," Dr. Reardon said. EMG has long provided a way for amputees to control prosthetic hands. But technologies that use the technique as a computer interface are only beginning to mature. In 2012, three Canadian entrepreneurs founded a company called Thalmic Labs, which built an armband called Myo that sent simple computer commands using hand gestures. With the swipe of a hand, for instance, you could switch to a new slide in a PowerPoint presentation. But the company discontinued the product several years later. Dr. Reardon started similar research after founding a company called Ctrl Labs with two other neuroscientists he had met in a Ph.D. program at Columbia University. In 2019, the start-up was acquired by Meta, where it now operates within a research operation called Reality Labs. Although Dr. Reardon and his colleagues have been privately demonstrating their technology for years, they are only now beginning to publicly share their work because it is now mature enough for the marketplace. The key development is the use of A.I. techniques to analyze the EMG signals. After collecting these signals from 10,000 people who agreed to test the prototype, Dr. Reardon used a machine learning system called a neural network -- the same breed of A.I. that drives ChatGPT -- to identify common patterns in this data. Now, it can look for these same patterns even when a different person is using the device. "Out of the box, it can work with a new user it has never seen data for," said Patrick Kaifosh, director of research science at Reality Labs and one of the neuroscientists that founded Ctrl Labs. According to Dr. Reardon, who is also known as the founding father of the Internet Explorer web browser at Microsoft, Meta plans to fold the technology into products over the next few years. Last fall, the company demonstrated how its wristband could be used to control an experimental version of its smart glasses, which can take photos, record videos, play music and verbally describe the world around you. Like technologies from Neuralink and Synchron, Meta's wristband could also provide new options for disabled people. Researchers at Carnegie Mellon are testing the wristband with people who have spinal cord injuries, allowing them to use smartphones and computers even though they do not have full use of their arms or hands. Most people with these types of injuries retain the ability to activate at least some of their muscle fibers. This allows the device to read what their brain is trying to do, even though their bodies can't actually make it happen. "We can see their intention to type," said Douglas Weber, a professor of mechanical engineering and neuroscience at Carnegie Mellon. In a similar way, Meta's wristband lets you control a computer with the appropriate thought. Merely thinking about a movement is not enough. But if you intend to make a movement, the wristband can pick up on what you aim to do -- even if you do not physically move. "It feels like the device is reading your mind, but it is not," Dr. Reardon said. "It is just translating your intention. It sees what you are about to do." When you move your arm or hand or finger, the number of muscle fibers you activate varies depending on how big or how small the movement is. If you practice using the wristband long enough, you can learn to activate a tiny number of fibers without actually moving your fingers. "We can listen to a single neuron. We are working at the atomic level of the nervous system."

Meta reveals wrist device that could replace mice and keyboards with hand gestures

Meta is working on some interesting things. Credit: Chesnot/Getty Images Researchers at Meta have developed a wristwatch-style tool that can interact with devices using hand gestures -- or even a thought. As the company detailed in a blog post, the Bluetooth device lets users control a computer with their "hand resting comfortably at [their] side." It allows the user to do obvious things like move a cursor around, but users can also type out messages by writing out the letters in the air. The device operates using "surface electromyography," a non-invasive way to track the electrical activity of muscles. "Based on our findings, we believe that surface electromyography (sEMG) at the wrist is the key to unlocking the next paradigm shift in human-computer interaction (HCI)," the company said in the blog post. Meta researchers also published a research paper about the device in the Nature science journal, which explained the new technology in slightly more complex terms -- "Here, we describe the development of a generic non-invasive neuromotor interface that enables computer input decoded from surface electromyography (sEMG)." According to Meta researchers, this breakthrough is possible in large part because of machine learning and AI. "Our neural networks are trained on data from thousands of consenting research participants, which makes them highly accurate at decoding subtle gestures across a wide range of people," the Meta blog post stated. In fact, Meta said this process was so effective that the device can even recognize your intent to perform a gesture, which could let you control a device simply by thinking. As Thomas Reardon, one of the authors of the Meta research paper, told the New York Times, "You don't have to actually move...You just have to intend the move." The wrist device could make computers more accessible to people with mobility challenges. That's because the device seems much less invasive than something like Neuralink, given that Meta's device doesn't require something to be implanted directly in your brain. Of course, Meta's blog post didn't give the device a name, price, or release date. It seems much more experimental in nature than something that's intended for mass market adoption in the near future. We'll keep you posted if that changes.

Meta's wristband breakthrough lets you use digital devices without touching them

Could Meta be on the verge of transforming how we interact with our digital devices? If the company's latest innovation takes off, we might soon be controlling our computers, cell phones and tablets with a simple flick of the wrist. Researchers at Meta's Reality Labs division have unveiled an experimental wristband that translates hand gestures and subtle finger movements into commands that interact with a computer. This allows a user to push a cursor around a screen or open an app without needing a mouse, touchscreen or keyboard. The technology can even transcribe handwriting in the air into text (currently at a speed of 20.9 words per minute). In a paper published in Nature, the team describes how its sEMG-RD (surface electromyography research) works. The wristband uses a technique called electromyography to pick up electrical signals when the brain tells the hand to perform an action. It then converts those signals into commands that control a connected device, such as your phone. Meta's breakthrough Meta's scientists are building on decades-old ideas, but they have taken them one step further. They used artificial intelligence to analyze large amounts of data from thousands of individuals who tested the prototype, identifying common patterns. So when a user now slips on a wristband, it can look for these patterns. Therefore, unlike previous gesture-detection systems that required training on specific individuals, Meta's wristband quickly assesses signals and adapts to the wearer. "To our knowledge, this is the first high-bandwidth neuromotor interface with performant out-of-the-box generalization across people," wrote the researchers. Applying the technology While there are plenty of possible commercial applications of the technology, such as in gaming and smart home control, the team is focused on helping those with severe disabilities. They are currently working with Carnegie Mellon to explore how this technology could benefit people with spinal cord injuries. That's because Meta's wristband is so sensitive it can pick up the faintest muscle activity, even when there's no visible hand movement. The intention to move is enough for the system to translate it into a command. This could allow individuals with complete hand paralysis to use a computer or other devices. There are many new technologies being developed for hands-free control, such as Elon Musk's Neuralink, which aims to plant chips in people's brains. Most are years away from being available. Meta's wristband, on the other hand, is not only noninvasive but, according to the researchers, could be available within the next few years.

Here's how Meta's new AI wristband works

The bracelet is designed to capture the intention behind muscle movement, even if the user's hand isn't touching a screen or surface. Imagine sending a text or playing a game without lifting a finger. Or at least, without moving it very much. This wristband, developed by Meta's researchers, might just make that real. The team recently published a study on a new wrist-worn device that turns the slightest muscle twitches into commands that a computer can understand. The "neuromotor wristband" is designed to capture the intention behind the movement, even if the user's hand isn't touching a screen or surface. It can detect and decode electrical signals produced by forearm muscles using artificial intelligence (AI). In a video demonstration, a user writes the words "hello world" in mid-air, and a visualisation of the corresponding text appears alongside. Meta also showed how people can move a cursor around a screen and play games using only finger taps or tiny hand motions. "It really is a somewhat breathtaking set of discoveries we have here," Thomas Reardon, vice president of research at Meta Reality Labs, said in a company-provided video explanation. Most brain machine interfaces available today require surgery. Meanwhile, the electrodes in the wristband pick up signals sent from the brain to the muscles, instead of putting the sensors directly in the brain by drilling into the skull. "We decided to take a different approach and record from the natural output of the brain. We don't need to go into your body to listen to [it]. We can do that from the side of the body," Reardon said. The wrist and forearm are packed with muscles that control hand and finger movements. These neuromuscular signals are processed in real time and send commands to computers via Bluetooth. The Meta team collected training data from thousands of participants to build an AI that works for users with different movement styles. The team says the wristband will be able to help a wide spectrum of users, from individuals with disabilities to everyday users. "We took the approach of saying, how would we build something such that it just worked right out of the box with eight billion people?" Reardon said. "This research that we're publishing demonstrates that there are some inherent, what we call scaling laws, that allow us to build a general model for really all of civilisation, such that people can put on a band and start using their brain directly," Reardon added. "They elect those signals from their brain in a general way to control a computer". Patrick Kaifosh, director of research science at Meta Reality Labs, said he expects "the technology to go a great deal farther". "What you've seen is these scaling curves continue as you get more people, more participants, data, it gets better and better," he added. Meta says it hopes that the study offers a blueprint to the broader scientific community "to create neuromotor interfaces of their own," according to a statement. It has recently released over 100 hours of muscle signal data from more than 300 participants.

Meta's wristband lets you type in the air with muscle signals

Using AI, Meta's wearable converts neuromuscular intent into real-time commands, enabling hands-free typing and gaming. Meta has engineered a wristband that enables users to type and interact with digital devices without physically touching a screen. This innovative device is designed to interpret the subtle intentions behind muscle movements, translating them into actionable commands. The core concept behind this technology involves capturing the user's intended actions by monitoring muscle activity. Meta's researchers have developed the wrist-worn device to convert slight muscle twitches into commands that computers can process, thereby creating a new interface paradigm. This approach eliminates the need for conventional input methods, such as keyboards or touchscreens, in certain applications. The wristband functions by detecting and decoding electrical signals originating from forearm muscles. Meta employs artificial intelligence (AI) algorithms to interpret these signals, enabling the device to understand the user's intended actions. The AI system is designed to discern patterns in muscle activity that correspond to specific commands or inputs. A demonstration of the wristband's capabilities featured a user writing "hello world" in mid-air. The corresponding text appeared on a screen in real-time, visualizing the translated muscle movements. This demonstration showcased the potential for the wristband to serve as a hands-free input device. Meta also demonstrated the wristband's ability to control cursor movements and facilitate gaming experiences. Using only finger taps or subtle hand motions, users could interact with on-screen elements and play games. This highlighted the device's potential for providing alternative control methods in various applications. Thomas Reardon, vice president of research at Meta Reality Labs, emphasized the significance of this development. He said, "It really is a somewhat breathtaking set of discoveries we have here," underscoring the potential impact of the technology. Apple might replace physical buttons with haptics Conventional brain-machine interfaces often require surgical procedures. In contrast, Meta's wristband offers a non-invasive approach. The device uses electrodes to detect signals transmitted from the brain to the muscles, bypassing the need for direct brain implants. Reardon explained this design choice: "We decided to take a different approach and record from the natural output of the brain. We don't need to go into your body to listen to [it]. We can do that from the side of the body." The wrist and forearm contain a concentration of muscles that govern hand and finger movements. The wristband leverages this anatomical arrangement to capture detailed neuromuscular signals. These signals are then processed in real time and transmitted to computers via Bluetooth technology, enabling seamless interaction with digital devices. To ensure the AI can accurately interpret diverse movement styles, Meta amassed training data from thousands of participants. This extensive data collection effort allows the AI to adapt to individual user characteristics, enhancing the usability and accuracy of the wristband. The Meta team envisions a wide range of applications for the wristband, extending from assisting individuals with disabilities to enhancing the experiences of everyday users. Reardon stated, "We took the approach of saying, how would we build something such that it just worked right out of the box with eight billion people?" Reardon further elaborated on the potential scalability of the technology: "This research that we're publishing demonstrates that there are some inherent, what we call scaling laws, that allow us to build a general model for really all of civilisation, such that people can put on a band and start using their brain directly. They elect those signals from their brain in a general way to control a computer." Patrick Kaifosh, director of research science at Meta Reality Labs, expressed optimism about the future development of the technology. He said he expects "the technology to go a great deal farther," suggesting ongoing improvements and expanded capabilities. Kaifosh added, "What you've seen is these scaling curves continue as you get more people, more participants, data, it gets better and better," highlighting the importance of continued data collection and research. Meta aims for this study to provide a foundation for further research in the field of neuromotor interfaces. According to a statement, Meta hopes that the study offers a blueprint to the broader scientific community "to create neuromotor interfaces of their own." As part of this commitment to open research, Meta has publicly released over 100 hours of muscle signal data obtained from more than 300 participants. This data is available to researchers and developers, fostering innovation in the field of neural interface technologies.

Meta unveils wristband for controlling computers with hand gestures - The Economic Times

Meta has unveiled a wristband that uses AI to interpret muscle signals, allowing users to control devices with subtle movements or even intent. Unlike brain implants, it requires no surgery. The technology, years in development, promises faster, touch-free interaction and potential life-changing benefits for users with physical disabilities.The prototype looks like a giant rectangular wristwatch. But it doesn't tell the time: It lets you control a computer from across the room simply by moving your hand. With a gentle turn of the wrist, you can push a cursor across your laptop screen. If you tap your thumb against your forefinger, you can open an app on your desktop computer. And when you write your name in the air, as if you were holding a pencil, the letters will appear on your smartphone. Designed by researchers at Meta, the tech giant that owns Facebook, Instagram and WhatsApp, this experimental technology reads the electrical signals that pulse through your muscles when you move your fingers. These signals, generated by commands sent from your brain, can reveal what you are about to do even before you do it, as the company detailed in a research paper published Wednesday in the journal Nature. With a little practice, you can even move your laptop cursor simply by producing the right thought. "You don't have to actually move," Thomas Reardon, the Meta vice president of research who leads the project, said in an interview. "You just have to intend the move." Meta's wristband is part of a sweeping effort to develop technologies that let wearers control their personal devices without touching them. The aim is to provide simpler, quicker and less awkward ways of interacting with everything from laptops to smartphones -- and maybe even to develop new digital devices that replace what we all use today. Most of these technologies are years away from widespread use. They typically involve tiny devices surgically implanted in the body, which is a complicated and risky endeavour. These implants are tested solely with disabled people who cannot move their arms and hands, and need new ways of using computers or smartphones. Neuralink, a Silicon Valley startup founded by Elon Musk, aims to implant chips under the skull, beside the brain. Synchron, run by an Australian neurologist, hopes to implant devices inside blood vessels in the neck. These efforts, like those of many other startups, aim to read brain activity directly -- an enormously complex process that must be tailored to the individual. Meta is taking a simpler approach. Its technology does not require surgery. Anyone can strap on the device and start using it. Using artificial intelligence techniques, Reardon and his team have identified common electrical signals that appear when a person moves a finger, wrist or thumb. "This idea -- this kind of technology -- is not new, it is decades old," said Dario Farina, a professor of bioengineering at Imperial College, London, who has tested the technology but was not involved in the research. "The breakthrough here is that Meta has used artificial intelligence to analyze very large amounts of data, from thousands of individuals, and make this technology robust. It now performs at a level it has never reached before." Meta's wristband uses a technique called electromyography, or EMG, to gather electrical signals from muscles in the forearm. These signals are produced by neurons in the spinal cord -- called alpha motor neurons -- that connect to individual muscle fibres. Because these neurons connect directly to the muscle fibres, the electrical signals are particularly strong -- so strong that they can be read from outside the skin. The signal also moves much faster than the muscles. If a device like Meta's wristband can read the signals, it can type much faster than your fingers. "We can see the electrical signal before you finger even moves," Reardon said. EMG has long provided a way for amputees to control prosthetic hands. But technologies that use the technique as a computer interface are only beginning to mature. In 2012, three Canadian entrepreneurs founded a company called Thalmic Labs, which built an armband called Myo that sent simple computer commands using hand gestures. With the swipe of a hand, for instance, you could switch to a new slide in a PowerPoint presentation. But the company discontinued the product several years later. Reardon started similar research after founding a company called Ctrl Labs with two other neuroscientists he had met in a Ph.D. program at Columbia University. In 2019, the startup was acquired by Meta, where it now operates within a research operation called Reality Labs. Although Reardon and his colleagues have been privately demonstrating their technology for years, they are only now beginning to publicly share their work because it is now mature enough for the marketplace. The key development is the use of AI techniques to analyse the EMG signals. After collecting these signals from 10,000 people who agreed to test the prototype, Reardon used a machine learning system called a neural network -- the same breed of AI that drives ChatGPT -- to identify common patterns in this data. Now, it can look for these same patterns even when a different person is using the device. "Out of the box, it can work with a new user it has never seen data for," said Patrick Kaifosh, director of research science at Reality Labs and one of the neuroscientists that founded Ctrl Labs. According to Reardon, who is also known as the founding father of the Internet Explorer web browser at Microsoft, Meta plans to fold the technology into products over the next few years. Last fall, the company demonstrated how its wristband could be used to control an experimental version of its smart glasses, which can take photos, record videos, play music and verbally describe the world around you. Like technologies from Neuralink and Synchron, Meta's wristband could also provide new options for disabled people. Researchers at Carnegie Mellon are testing the wristband with people who have spinal cord injuries, allowing them to use smartphones and computers even though they do not have full use of their arms or hands. Most people with these types of injuries retain the ability to activate at least some of their muscle fibers. This allows the device to read what their brain is trying to do, even though their bodies can't actually make it happen. "We can see their intention to type," said Douglas Weber, a professor of mechanical engineering and neuroscience at Carnegie Mellon. In a similar way, Meta's wristband lets you control a computer with the appropriate thought. Merely thinking about a movement is not enough. But if you intend to make a movement, the wristband can pick up on what you aim to do -- even if you do not physically move. "It feels like the device is reading your mind, but it is not," Reardon said. "It is just translating your intention. It sees what you are about to do." When you move your arm or hand or finger, the number of muscle fibers you activate varies depending on how big or how small the movement is. If you practice using the wristband long enough, you can learn to activate a tiny number of fibres without actually moving your fingers. "We can listen to a single neuron. We are working at the atomic level of the nervous system."