Brain-Computer Interface Advances Help Reconnect the Mind and Body

In the 1870s, scientists discovered that mammalian brains carried electric current, paving the way for the field of neurophysiology.¹ Nearly a century later, Jacques Vidal, a computer scientist at the University of California, Los Angeles, published a landmark paper proposing the idea of brain-computer interfaces: a direct communication link between the brain and an external device like computers or prosthetics via the brain’s electrical activity.

The idea, which seemed like science fiction four decades ago, eventually gained momentum, with various researchers offering proofs-of-concept with real-world applications. Read on to learn how brain-computer interfaces have allowed people with motor or speech dysfunctions to control robotic limbs, communicate, and regain sensation.

Brain-Computer Interface Devices Drive Advances in Neuroscience

While brain-computer interface devices have obvious clinical applications, makers of the technology also understand its implications for better understanding the human brain. Beyond helping people with motor or speech dysfunction, recording brain activity can help scientists decode neural dynamics. With new and improved devices making it to the market, researchers can now obtain unprecedented insight into the inner workings of the brain, which can in turn improve the design of brain-computer interface devices.

Pushing for Brain-Computer Interface Technologies That Last a Lifetime

With brain-computer interfaces becoming a more practical reality for people with paralysis, bioengineers are facing logistical hurdles in designing these devices. Once implanted into the human brain, the devices experience attacks from resident immune cells, leading to fibrosis and damage to the probe. Now, researchers are exploring different materials and engineering new designs to develop technologies that will withstand these challenges. Such advances could ensure that patients do not need repeated brain surgeries to implant new devices.

The Early Success of Brain-Computer Interface Implants

A brain implant helped a man who was completely paralyzed to communicate with his family when doctors placed a chip in his brain’s motor cortex. After initial unsuccessful attempts, a team of researchers led by Niels Birbaumer, a retired neuroscientist at the University of Tübingen, decided to try a method where the man listened to a tone and learned to change the tone by thinking specific thoughts. This enabled the man to communicate single words. Eventually, he was able to compose whole, intelligible sentences, even sending a message to his son.

Brain Implant Helped a Man With Paralysis Regain Sensation

A diving accident in 2020 left Keith Thomas paralyzed from the chest down, without any sensation in his hands or wrists. Doctors implanted electrode arrays in Thomas’s brain that could read his brain activity and deliver electrical stimulation. A research team led by Chad Bouton, a bioelectronic medicine researcher at Northwell Health, recorded Thomas’s brain signals when he imagined the sensation of touch, conveying these signals to his muscles through wearable stimulation patches on his skin and into the sensory areas of his brain. Thomas regained the ability to feel touch in his right wrist about six months after the device was implanted, and he could eventually wipe his nose or scratch his mouth when using the device.

Speech Brain-Computer Interface Deciphers Users’ Thoughts

While brain-computer interface devices can help users by translating their brain activity into speech, this can also leave the users fatigued. To bridge this gap, Francis Willett, a neurosurgeon at Stanford University, and his team developed a speech brain-computer interface with the ability to decode imagined sentences. They trained machine learning algorithms to decipher neural patterns linked with imagined speech, allowing people to communicate audibly by just thinking about what they wanted to say.