The Devices That Will Read Your Brain—and Enhance It

That’s the future technologists imagine, and a variety of devices are being developed to enhance the brain’s performance in day-to-day life.

Right now, the market for devices that can read brain activity and translate it into actions is in its infancy. But, thanks in part to Elon Musk’s startup Neuralink, which is developing implantable brain-computer interfaces—or BCIs—that can record data from thousands of brain cells, investment and interest in these devices have soared in recent years.

New wearable devices designed to provide feedback during day-to-day activities build on implantable BCIs used for medical interventions, as well as decades of research into how the brain works. Efforts on implantable devices focus on restoring function. Applications aimed to allow communication and movement have been in development for decades to help paralyzed patients, and researchers have made major leaps with implantable devices in recent years, including giving voice back to the voiceless.

Last year, Neuralink showed that a monkey could control a cursor with its mind and type out a message. A Neuralink competitor, Synchron, showed that paralyzed patients implanted with its brain-recording device could use their brain signals to text with an iPhone.

While implants could help many patients, these devices are unlikely to become blockbuster mass-market consumer products anytime soon because of federal medical-device regulations, high costs and the inherent risks of brain surgery. Technological constraints also now limit the amount of data that can be collected from the brain. For instance, implanted devices can get hot and damage brain tissue as more data gets extracted from the brain, similar to a smartphone overheating if too many apps are running. Putting too many needlelike sensors into the brain might also cause damage.

But wearable brain-sensing devices—as opposed to implanted—could offer a broader swath of consumers cognitive feedback and other brain enhancements. That’s already happening in university and company labs. Several recent studies using simulators have shown that wearable BCIs can detect drowsiness and fatigue and give real-time, AI-powered feedback to drivers to help prevent crashes.

This tech could bust out of the lab and begin going mainstream as soon as the next year. Among the initial goals: improving concentration and helping consumers boost productivity and reduce burnout by alerting users when their attention wanders. Boston-based neurotech startup Neurable expects to sell a pair of headphones with brain-activity monitors to track focus in early 2024.

Non-implantable BCIs with sensors called fNIRS—short for functional near-infrared spectroscopy—detect changes in blood oxygen levels, which serve as a proxy for brain activity. Labs have used fNIRS devices to measure the impact of music on the brain, as well as to assess professional skills. Companies are working to make the devices easier to wear. Electroencephalogram, or EEG, sensors measure tiny differences in electrical activity at various points on the head. EEG sensors can be used to diagnose conditions like epilepsy or, as in Neurable’s case, to track focus. Brain cells, called neurons, produce billions of electrical signals that relay information across the brain and body.

Improved communication, collaboration, and social interactions are among the enhancements that BCI developers are working to realize in coming years by combining high-quality brain-activity recordings with information from activity sensors, food diaries, sleep logs, eye trackers and other data sources.

“It’s the relation of brain activity and data to the outside world—to our behavior, to our mood—that will probably push forward a huge amount [of applications] in the coming decade," said Sumner Norman, a neuroscientist and co-founder of Forest Neurotech, a company developing implantable BCIs.

Santa Barbara, Calif.-based startup Cognixion is beginning to pair brain data with other biometrics in its augmented-reality headset, which has wearable brain-monitoring and head-motion sensors and is compatible with eye-tracking sensors, according to Andreas Forsland, the company’s chief executive. The device is now sold for research purposes, but the plan is for patients with motor and speech disorders to use it to communicate with people and their devices. Forsland says the headset can already link up with Amazon’s Alexa voice assistant.

“The most important thing is to get the data out," said Matt Angle, CEO of Paradromics, which is developing implantable BCIs. “If you don’t have a lot of good data coming out of the brain, then you’re done for to begin with."

For consumer wearables, that’s a big challenge because they don’t have direct access to the brain. They detect brain activity through the skull and hair, like microphones trying to listen in on a conversation through a wall. Companies are working on building better, smaller sensors and more powerful AI algorithms to decode those lower-quality signals to enable a future in which wearable BCIs are an integral way of controlling the devices around us and learning about ourselves, experts said.

Applications for the next generation of wearable BCIs could include diagnosing mood disorders, which affect millions of people worldwide, as well as providing feedback that enhances mindfulness, deciphering product and musical preferences, and enabling touch-free typing and controlling devices with our minds, experts said.

“It’s a new way of thinking about how we interact with technology," said Nita Farahany, a neuroethicist at the Duke University School of Law, who says cognitive privacy rights are needed.

AI will fast-track the advent of this new brain-powered technological future, brain experts said. It could also supercharge the value of personal data, creating new concerns about cognitive privacy. The more information that’s collected, the more accurately AI systems could learn individual preferences and become more efficient at decoding thoughts and intentions, Farahany and others said—an advance that could hold privacy risks.

“It’s a huge untapped market," she said. “It’s not surprising that people are going after it."

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