We are not strangers to the unprecedented ways that new technological devices can reshape society. In the last decade, we have witnessed how things like smart phones and social media have dramatically altered how we, as humans, interact.

One of the major technological advances that will likely continue to shape our human interactions is brain computer interface (BCI) technology. In this post, I am going to delve into the history of the BCI and look at some of the current developments happening in the realm of BCI technology.

The Biology of the Brain

To understand BCIs, you must first understand the basic biology of the brain. The brain is divided into seven sections, each of which is generally responsible for a certain type of activity. For example, the brain stem controls basic functions, the hippocampus controls memory, and the cerebellum is responsible for motor control.

BCIs primarily focus on the prefrontal cortex of the brain, which is responsible for higher thinking. The prefrontal cortex makes up the outer layer of the brain, making it the most accessible for neurological research.   

Messages travel throughout the brain and to the rest of the body via a vast network of neurons. In fact, there are over 86 billion neurons in the brain alone. 

Neurons are long cells that transmit electrical impulses from one part of the body to another. One side of the neuron’s cell body has appendage-like structures called dendrites that receive messages from other nerve cells. The messages pass across the neuron to the long fiber tail on the opposite end, called the axon, which transmits the message to the dendrites of neighboring cells. 

Messages travel across a single neuron using electrical impulses. However, to get the message from one neuron to the next, the neurons rely on a chemical process called neurotransmission. In neurotransmission, the messages are passed from neuron to neuron across small junctions called synapses using chemical communication.

This neuron communication is what creates the electrical signals within the brain. When scientists detect electrical spikes within certain areas of the brain, they’re actually detecting clusters of neurons firing in a single area. This neurological communication in the brain is the basis for the BCI technology that is used today. 

The History of Brain Computer Interfaces

Humans have always been interested in the brain. In fact, nearly every early civilization has some record of research or philosophy surrounding the brain. However, early civilizations did not possess the means to obtain the knowledge they sought. It wasn’t until the late 1800s that humans developed the technology required to begin to delve into the complex functionality of the human brain.

Richard Caton, a physician in Liverpool, first determined that the brain was electrical in 1875. Using a galvanometer on rabbits and monkeys, Caton was able to detect the electrical currents in the brain. His research was corroborated by Polish physician Adolph Beck in 1890, whose research was the first to identify brainwaves. 

In 1912, Ukrainian physiologist Vladimir Pravdich-Neminsky completed the first electroencephalography (EEG) on a mammalian brain using a string galvanometer. The first EEG of a human was completed in Germany in 1924 by Hans Berger. 

An EEG is an electrophysiological method for monitoring electrical activity in the brain. Early EEGs were non-invasive, meaning measurements were taken without penetrating the skull. Sensors that measured the electrical currents of the brain were placed on the subject’s head and the results were transcribed as wave-like readouts. 

The early EEGs detected Alpha brainwaves, the brainwaves that are present in the brain’s resting state. However, in the 1930s, British neurophysiologist William Grey Walter improved the EEG machine. The upgraded machine was able to pick up Alpha brain waves as well as Delta brainwaves, the brain waves associated with deep sleep.

The use of EEGs rapidly gained popularity in the 1930s. The first practical applications used the EEGs to detect and monitor epileptic seizures. However, as the science continued to mature, psychology and neuroscience began to use the EEG for additional applications, including diagnoses of brain tumors, brain damage from injuries, and dysfunctions from inflammation, strokes, and infections. 

Walter continued to push neuroscience forward throughout his career. In 1957, he developed the first toposcope, a machine that was able to measure where in the brain different neurological responses were located. In 1964, he developed the first BCI, a machine that allowed people to move a slide projector forward simply by thinking about it. 

Walter’s research raised some of the first ethical and philosophical conversations surrounding modern neurological research. For example, in his slide projector experiments, many of the participants didn’t feel like they had made the decision to move the slide projection; they had only thought about potentially making the decision to move it. This raised the philosophical question of whether or not the brain is actually able to make concrete decisions. 

The physiological and neurological sciences weren’t the only ones to get involved in the EEG craze. In 1965, Alvin Lucier performed a song, entitled “Music for Solo Performer,” using only his Alpha brainwaves. Though the song was more interesting theoretically than musically, it nonetheless began to bring attention to the potential of BCIs. 

The term “Brain Computer Interface” was finally coined by Jacques Vidal of UCLA in 1973 when he published the first peer-reviewed papers on the topic. In 1976, he used a non-invasive EEG to have participants control a cursor on a computer screen and move it through a maze. The idea of using EEG signals to control an object was expanded on and, in 1988, the first use of telekinesis to control a robot was recorded. 

In 1999, the first evasive EEG was performed. Invasive EEGs go through the skull and plant sensors directly into the brain. These EEGs hold more risk, but are also able to much more efficiently read the neurological responses of the different sections of the brain. 

The invasive EEG led to a breakthrough in prosthetics and, for the first time, a quadriplegic was able to control the basic movement of a prosthetic hand. With the invasive EEG, the field began evolving at a rapid rate. 

In 2004, a monkey was able to control a robot arm to feed itself. In 2008, the Voiceless Phone Call was designed for people who are unable to speak. An individual could use a neckband and, just by thinking a message, they were able to transmit messages using up to 150 different words.

All of these advancements that have been made since Richard Caton’s discovery in 1875 have paved the way for the BCI technology that we see today.   

Brain Computer Interface Devices Used Today

Though many people have not heard of BCIs, they have likely heard of at least one of the BCIs that are in use today. Some of the most prevalent BCIs include:

• Cochlear Implants: Cochlear implants are surgically-implanted neuroprosthetics that help people with moderate to severe hearing loss. The implants replace normal acoustic hearing with electric signals that stimulate the auditory nerve. 
• Visual Prosthesis: The visual prosthesis is an experimental vision device that was released in 2012. The goal of visual prosthesis, also known as bionic eyes, is to restore functional vision for individuals with loss of sight. 
• Deep Brain Stimulation: Deep Brain Stimulation is a neurosurgical treatment for Parkinson’s, multiple sclerosis, and dystonia. Electrodes are placed inside the brain and electrical impulses are used to regulate the area of the brain that controls movement. 
• BCI Limb Prostheses: BCI limb prostheses are prostheses that are controlled by the brain. 
• Brain-to-Brain Interfaces: Brain-to-brain interface is a new experimental technology that directly links the brains of two or more creatures to allow them to communicate directly. At this time, the technology is still in the research phase.  
• Hippocampal (or cognition) Prostheses: The hippocampal prostheses are being developed to help patients with Alzheimer’s and other neurological disorders enhance their ability to think and remember. The prosthesis will need to function like a healthy hippocampus to be successful. 

As BCI technology continues to evolve, the market continues to grow. In fact, by 2026, BCI technology is expected to be a $26B market. Given the success of the field, there are numerous start-up companies currently researching and creating BCI technology. Some of the notable startups include:

• Kernel Co. ($107M): Known for their work on hippocampal prostheses.
• MindMaze ($110M): Known for their work on 3D camera capture for patients with brain injuries to simulate motor functions during rehabilitation.
• Neuralink ($158M): Known for the Neuralink implant.

Neuralink

Neuralink Corporation is an American BCI start-up that was founded in 2016. Its association with Elon Musk, along with its well-publicized research, has made it one of the most well-known BCI companies. 

Neuralink has followed in the footsteps of BrainGate, a nonprofit organization that has done extensive research on BCI implantations. In 2006, BrainGate created a device that implanted 100 stiff electrodes under the skull to gain more information about the brain and what causes specific neural clusters to activate. Neuralink has improved on the invasive EEG technology developed by BrainGate to create the Neuralink. 

The Neuralink is a device that is installed in a mammalian brain through a 45-minute invasive surgery. The device includes 1024 implants (aka threads) that are placed in various locations throughout the brain. Each implant is approximately 1/20th the size of a hair. The implants connect to a central device that sits between the brain and the skull and transmits data to outside devices via Bluetooth communication. 

The Neuralink implants are robotically placed in the brain to ensure that no capillaries are hit during the implantation. The robot is able to track the motion of the brain and capillaries so that it can place the implants without damaging brain tissue.  

During a Progress Update delivered in August 2020, Neuralink stated that the Neuralink device had successfully been implanted in pigs. They found that the implant could safely be left in place for at least two months, and could also be removed successfully.  

Main Challenges for Neuralink

The main challenges facing the Neuralink BCI include:

• Materials Science: The brain is such a corrosive environment that it quickly degrades any implanted material. It is a challenge to find a non-toxic, non-corrosive material that can be made thin enough to coat the implants. The probe must be protected but still able to serve its function of reading, writing, and transmitting data.
• Implants: The implanted threads must be as thin as possible to minimize impacts to the surrounding brain tissue. However, the thinner you make the thread, the more challenging signal conduction is because the cross-sectional area is smaller.  
• Access: For the technology to be successful, the implant will eventually need to access deeper areas of the brain that have not yet been reached with EEG implants. 

Neuralink Short Term Goals

Neuralink was created to eventually be a reliable and affordable device that could be used to treat a wide range of neurological problems. In the short term, the team is focusing their treatments for blindness, hearing loss, and paralysis, as all of these issues can be tackled using outer areas of the brain.  

Neuralink Long Term Goals

Long term, Neuralink hopes to continue to improve on its implantation technology to expand beyond medical applications. Some of the long term goals for the employees of Neuralink include:

• Application Programming Interfaces (API): Using the BCI implants for entertainment like playing video games and having interactive experiences. 
• Enhance and Improve Cognition: Using the BCI implants to continue to improve human cognition beyond normal capabilities. 
• Upload Our Brains: Using the implant to copy your brain so that, should something happen to your body, you could upload your brain into a new body or a robotic body. 
• Compete with Advanced AI: This objective is Elon Musk’s main objective. According to Musk, AI will eventually become intelligent enough to destroy humanity. Therefore, in a “if you can’t beat them, join them” mentality, Musk hopes to eventually merge humans with AI, thereby allowing humans to direct AI as it evolves. 

Neuralink’s 2020 Progress Update Criticisms 

Neuralink’s 2020 Progress Update was not without its fair share of criticism. Within the neuroscience community, there seemed to be a general lack of enthusiasm about what was ultimately presented. Many claimed that while the engineering was impressive, the presentation did not actually show any neurological science that hadn’t already been done before. 

There is also some bitterness towards Neuralink within the neuroscience community. In a field that has historically been relatively collaborative, many are frustrated that Neuralink is not sharing more of their data. By keeping their work private, Neuralink is potentially hindering the speed at which the field could be progressing. 

The Neuralink implant has also opened up a wide range of ethical criticisms, including:

• Security and Privacy: The Neuralink forces one to question who owns the data that will be extrapolated from the brains of the subjects. According to today’s laws, it is possible that the subjects in the studies would not actually have a legal claim to the data drawn from their brains. 
• 2-Tiered Society: Some worry that this technology will continue to polarize our society into the “haves” and the “have-nots.” If this technology is expensive, it will allow those individuals with financial access to the devices to further augment their abilities and maintain their elevated place in society.  
• Physiological Impacts: The physiological impacts of these devices will likely be studied sufficiently and are therefore not one of the larger concerns. However, their unprecedented nature does mean that the standards by which physiological impacts must be measured are not yet set. 
• Psychological and Behavioral Impacts: Imagine a world where everyone was 100 times smarter or capable of telepathy. How would that impact our behavior and psychology? We have already seen, though smartphones and social media, how technology can have unexpected impacts. It is therefore possible that the full extent of the psychological and behavioral impacts of this technology will not be fully grasped until well after the technology has established itself. 

The fascinating thing about BCI technology is that the future potential is limitless. Even within Neuralink, the employees maintained vastly different hopes and goals for their research. For example, some people were interested in medical applications, while others were interested in finding a way to store memories to keep from forgetting things. With such a vast array of potential applications, the future of BCI technology is completely undetermined.