Mind-reading sounds like a superpower reserved for superheroes in science fiction films, or illusionists in entertainment shows. However, the truth is that mind-reading devices, also known as Brain-Computer Interfaces (BCIs), exist in reality and provide solutions for patients with various neurologic and motor conditions. From granting people with paralysis the ability to move their limbs again to restoring sight to the blind – join us on a journey into the fascinating world of devices that transform the lives of many.
Cracking the Mystery of the Human Brain

At the heart of Brain-Computer Interfaces is the complex relationship between the human brain and its electrical activity. The human brain generates electric signals every time we think, move or perceive the world around us with our various senses. Brain-Computer Interfaces take advantage of this phenomenon by utilizing advanced technologies meant to identify and interpret these electric signals, then translate them to executable commands for computers or external devices.

Managing to Walk Again

One of the primary methods utilized in Brain-Computer Interface technology is the EEG test – A noninvasive technique which records brainwave patterns using electrodes placed on the scalp. EEG permits the recording of brain activity close to the scalp – in the region known as the cerebral cortex – where, among other things, most motor commands allowing control of muscles are issued. A large number of technologies were developed based on this principle in order to make it possible for paralyzed patients to restore their movement capability using a robotic exo-skeleton, to which the command to move is issued once the signal from the patient’s brain is read.

Another approach involves surgical implantation of micro-electrodes directly into the brain, providing accurate and detailed readings from deeper areas of the brain, which an EEG cannot read, as well. One of the most recent breakthroughs in this occurred in May 2023, when a group of researchers from Switzerland succeeded in restoring the walking function in a young man with a spinal cord injury, whom is paralyzed from the neck down. The researchers utilized an implant based on an array of electrodes that received signals from the patient’s brain and transmitted them to another implant in his spine – thus creating, in practice, a bypass around the damaged area.

Let There Be Light

In October 2021, the results of a clinical study which managed to restore some components of vision in a patient that lost her sight were published. This breakthrough was made possible thanks to an implant in the visual cortex region of the patient’s brain, which transmitted electrical signals into it from a computer that received images from a camera. Unlike movement restoration, where the implant receives an electric signal from the patient’s brain and transfers it to a robotic exo-skeleton to generate the movement, in visual restoration, the purpose of the implant is to generate signals in the brain based on an image captured by a computer, in order for said signals to be interpreted as visual input.

Restoring Voice

Another role of Brain-Computer Interfaces is in aiding patients who lost their ability to speak due to degenerative damage. In a study published in the scientific journal Nature in May 2021, a group of researchers created an electrode implant that successfully identified which letters a patient intended to write via brain signals, and translated them to written text on a computer.

Another study published in May 2022 presented the exciting results of the use of an implant in a young patient with ALS who lost the ability to move his facial muscles. Using a neurofeedback system, the patient had learned to generate specific brain signals translated by a computer into “yes” or “no” answers. Afterwards, researchers played back the sequence of the alphabet, and the patient selected a desired letter by sending an appropriate signal, until complete sentences were assembled by the computer.

Looking Ahead

Brain-Computer Interfaces have a significant potential to assist with a variety of conditions and restore other important functions that were lost – and technology is expected to improve, with smaller and easier to implant devices.
Alongside its massive promise, this technology is not without its challenges and raises important ethical questions that we will be required to engage with as devices continue to become more advanced.