Brain-computer interfaces (BCI) are increasingly becoming reliable pieces of technology, changing the lives of patients, particularly of patients who suffer from paralysis or similar conditions. BCI is defined as computer technology that can interact with neural structures by decoding and translating information from thoughts (i.e., neuronal activity) into actions. BCI technology may be used for thought-to-text translation or to control movements of a prosthetic limb. The umbrella term BCI covers invasive BCI, partial invasive BCI and non-invasive BCI. Invasive BCI includes the implantation and use of technology within the human body, such as surgically placed electrodes to directly detect electrical potentials. Partial invasive BCI devices are external recorders that detect signals from superficially implanted devices. An example of partial invasive BCI is electrocorticography (ECoG), which records activity of the brain via an electrode grid that was surgically embedded. The previous example is considered “partial” because the electrode grid is placed directly on the brain, but not permanently implanted inside of the brain. Non-invasive BCI technology involves external sensors/electrodes, as seen with electroencephalography (EEG).
BCI research intends to restore and enhance neural features of the central nervous system by linking it to a computer system. A professor at the University of California, Jacques Vidal, coined the term BCI in the mid-late 1900’s. The earliest published experiment, published in the year 1977, consisted of moving a cursor on a screen based on EEG waves. This experiment was monumental for the field of BCI, because it was the first recorded successful use of BCI in the laboratory. Importantly, this work proved feasibility and paved the road for further research developments. There has been much additional research on BCI since then, including groundbreaking work that used BCI devices to assist blind people navigate their environment. Perhaps the best-known application of BCI technology is in the form of neural prosthetic devices. An example of this type of BCI is a cochlear implant.
A recent study at Stanford University highlighted why BCI technology will continue to grow in relevance to the medical field. The study describes the application of BCI technology to three paralytic patients (two with amyotrophic lateral sclerosis (ALS) and one with a spinal cord injury). In the study, these patients could successfully move an onscreen cursor by imagining the necessary hand movements. To enable this remarkable feat, each patient had electrodes implanted into their motor cortex to record brain signaling and to transmit signals to a computer.
BCI technology has also been used to help ALS patients suffering from varying degrees of “locked-in syndrome” and has provided the means for them to communicate using humanoid robots. Humanoid robots are robots that are designed to have the shape of a human body. Post-hoc analysis of the preliminary data indicates that such patients can communicate using humanoid robots to accomplish routine tasks, such as retrieve mail or pick up a plate to eat dinner from. This technology could potentially be life changing. Before this type of research, patients solely depended on a caregiver, such as family members or friends to accomplish simple tasks.
A project called “Brainternet” is generating additional excitement for the field of BCI technology by converting the brain of a user into a node for the internet of things (IoT), which allows a “plugged-in” brain to connect to the internet. A headset of electrodes is attached and action potentials are detected and then transmitted to a small receiver called a Raspberry Pi. This device acts to convert brain activity into signals uploaded to public domains on the internet. The process can be tracked in real time. Once connected, a user can communicate with other users online by using brainwaves detected via an EEG device.
The possibilities of BCI technology are nowhere near exhausted. The emergence of non-invasive BCI devices — based off an EEG — is emblematic of future mainstream accessibility of BCI technology. For example, BCI technology can allow users to create music with their thoughts. The specific device for this is called an encephalophone, which is controlled by the visual or motor cortex. The device works by receiving input from cortical signals such as the posterior dominant rhythm (PDR) from the visual cortex or the mu signal from the motor cortex. This technology can be used by people who suffer from neurodegenerative conditions, but most likely will also become a mainstream product.
In conclusion, BCI has progressively achieved several monumental milestones. The future impact of BCI in terms of patient care is slowly starting to come into focus. It is important to remember that the generation of physicians that we belong to will be in charge of knowing and integrating new technology, to provide better care to our patients.