A motionless piece of hardware, meshing with the most complex biological system in the universe. Together, a technology that has the power to manipulate and control our every action, thought, and desire.
Brain-Computer Interfaces are tools of science-fiction becoming scientific realities right in front of our eyes. If you had told me about BCI’s just a couple of months ago, I would have told you that you’re out of your mind.
But in the last few weeks, I’ve learned that the idea of converting brain signals into an external, artificial output that replaces, restores, enhances, or supplements natural nervous function might not be as impossible as I had previously thought.
Yet, it is seemingly difficult to find a place to begin when discussing such a complicated technology. So let’s start at the very beginning.
Breaking Down the Nervous System
Contrary to popular belief, the nervous system doesn’t just include the brain, but rather spans the length of an individual’s body. It allows organisms to sense, organize, and react to information in the environment.
The nervous system is commonly divided into the central nervous system (CNS) and the peripheral nervous system (PNS). The central nervous system is made up of the brain, its cranial nerves, and the spinal cord. The peripheral nervous system is composed of the spinal nerves that branch from the spinal cord and the autonomous nervous system, which is divided into the sympathetic and parasympathetic nervous systems.
The brain and spinal cord of the central nervous system are protected by the vertebrae and the skull, while the nerves and cells of the peripheral nervous system are not enclosed by bones, making them more susceptible to trauma.
If we were to consider the entirety of the nervous system as an electrical grid, the central nervous system would represent the powerhouse, the peripheral nervous system would represent the cables that connected the powerhouse to the surrounding cities, bring them electricity, and bring information back to the powerhouse about their status. The cities represent limbs, glands, and organs.
Essentially, signals from the brain and spinal cord are relayed to the peripheral system by motor nerves, which tell the body to move or conduct basic life functions such as breathing, salivation, or digestion. In turn, the peripheral nervous system sends back the status of the limbs, glands, and organs by relaying information through sensory nerves.
Now we’ve broken down the nervous system, let’s focus on the part that you’ve all been waiting for.
You guessed it brainiac; let’s talk about the brain.
Bingo! The Brain
Essentially, the brain is divided into two main sections; the limbic system and the neocortex.
The limbic system is responsible for our primal urges, as well as those related to survival, such as eating and reproducing. It is responsible for reward-seeking and is stimulated by social and emotional variables.
The limbic system develops earlier and faster than the cortex, so until the growth of the cortex catches up with the limbic system in early adulthood, the desire for rewards and social pressures overrides rational thinking.
The neocortex is the brain’s most advanced area. It is involved in higher-order brain functions including sensory perception, cognition, generation of motor commands, spatial reasoning, and language, and higher-order thinking in regards to topics including technology, business, and philosophy.
The cerebral cortex is the outermost layer of the brain, made up primarily of gray matter. These are essentially processing areas of the brain that interpret signals generated in the sensory organs or in other areas of gray matter in the brain.
The cerebral cortex is the most prominent visible feature of the human brain, and although it is only a few millimeters thick, it makes up about half of the weight of the brain.
The surface of the cerebral cortex is extensively folded, forming ridges called gyri and valleys called sulci. The intricate folding allows for the surface area of the cerebral cortex to be increased significantly, making room for more neurons.
The cerebral cortex can be divided into four sections; the frontal, parietal, occipital, and temporal lobes. Each has a different function ranging from reasoning to auditory perception.
1. The Frontal Lobe
The frontal lobe is located at the front of the brain and is associated with reasoning, motor skills, higher-level cognition, and expressive language. At the back of the frontal lobe lies the motor cortex, which receives information from various lobes of the brain, and uses it to carry out body movements.
2. The Parietal Lobe
The parietal lobe is located in the middle section of the brain and is associated with processing tactile sensory information such as pressure, touch, and pain.
3. The Occipital Lobe
The occipital lobe is located at the back portion of the brain and is associated with interpreting visual stimuli and information. The occipital lobe includes the visual cortex, which receives and interprets information from the retinas of the eyes.
4. The Temporal Lobe
The temporal lobe is located on the bottom section of the brain. It is the location of the primary auditory cortex, which interprets the sounds and the language we hear. The hippocampus is also located in the temporal lobe, the portion of the brain heavily associated with the formation of memories.
We know the different segments of the brain, but what is this tissue comprised of? Let’s zoom in a little more to look at to take a look at neurons, the basic working unit of the brain.
The Nimble Neuron
The basic functional units of the central and peripheral nervous system are neurons.
Neurons are the fundamental units of the brain and nervous system; the cells responsible for receiving sensory input from our surroundings, sending motor commands to our muscles, and transforming and relaying the electrical signals at every step in between.
The interactions between neurons, called synapses, are our working train of thought.
Their interactions define who we are as people.
Each neuron is comprised of three basic parts; the cell body, axon, and dendrites. They can be thought of as the trunk, roots, and branches of a tree, respectively.
The cell body maintains the structure of the neuron and houses the neuron’s energy source, DNA, and forms proteins that are to be transported throughout the axon and dendrites.
The axon, represented as tree roots, is the output structure of the neuron; when a neuron wants to talk to another neuron, it sends an electrical message called an action potential down the axon.
The dendrites, represented as tree branches, are where neurons receive input from other cells. Dendrites branch out as they move towards their tips, similar to tree branches.
Neurons communicate with each other and junctions between dendrites, called synapses. At the synapse, a neuron sends a message to another target neuron. Most synapses are chemical. They communicate through the transmission of neurotransmitters, chemical messengers that transmit a message from a nerve cell across the synapse to a target cell. Other synapses are electrical, where ions flow directly between cells to transmit information.
So how does this have anything to do with a Brain-Computer Interface?
What is a Brain-Computer Interface?
While there isn’t exactly a simple way to put it, a brain-computer interface is essentially a direct communication pathway between an enhanced or wired brain and an external device.
Woah. Let’s rewind.
While there isn’t exactly a simple way to put it, a brain-computer interface is essentially a direct communication pathway between an enhanced or wired brain and an external device.
How is that even possible?
BCI’s take a multi-step approach when connecting the brain with an external device.
Measure brain activity → extract features from that activity → convert those features into outputs that replace, restore, enhance, supplement, or improve human functions.
The Different Types of BCI’s
BCI’s are either invasive, noninvasive, or semi-invasive, each penetrating into the brain at various levels. Depending on the type of Brain-Computer Interface, the brain signals will be measured from a certain part of the brain.
Noninvasive — The electrodes are placed on the scalp to measure the electrical potentials produced by the brain (EEG) or the brain’s magnetic field (MEG).
Semi-invasive — The electrodes are placed on the exposed surface (dura or arachnoid) of the brain (ECoG).
Invasive — The micro-electrodes are placed directly into the cortex, measuring the activity of a single neuron.
An EEG, or an electroencephalogram, is a non-invasive BCI that detects electrical activity in the brain using electrodes, minuscule electrical conductors, attached to the scalp. It records the brain’s electrical activity from the surface of the scalp, as neurons at the surface of the brain are constantly communicating through electrical impulses.
EEG’s pick up signals through voltage shifts inside neurons. Sodium (Na+) channels open along the dendrites, causing a flood of positive electrons. The positive charge rushes down the axon, opening more sodium channels.
This electrical charge carried down the axon is discharged at the synapse and releases neurotransmitters in the process. When groups of neurons fire together, they provide enough electrical signals for us to measure from the scalp. However, EEG’s are only able to measure clusters of neurons, which are about the size of a quarter in diameter.
Despite this limitation, EEG’s still prove to be advantageous as they are portable, whereas technologies such as MEG’s require specially built rooms. In recent years an increasing number of commercial EEG systems have been released, making them more affordable and accessible to the general public.
EEG data contains rhythmic activity, which reflects neural oscillations, or brainwaves. Oscillations are rhythmic or repetitive patterns of neural activity in the central nervous system and are characterized by their frequency, power, and phase.
Incidentally, research has found associations between the frequency of neural oscillations (the rate at which they occur) and different brain states. Oscillations are categorized as either alpha, beta, delta, gamma, and theta based on their frequency.
For example, researchers have found that commercial EEG headsets, typically measure the amount of brain activity that occurs in the alpha frequency, as they are primarily used for tasks such as meditation as alpha oscillations have slower frequencies.
The spatial resolution, or clarity of signals, being produced by an EEG is determined by the number of electrodes used. Typically, at least 32 electrodes are used, the most being around 256.
The spatial resolution for EEG is quite low compared to semi-invasive techniques such as ECoG’s and fMRI’s because the signal needs to travel through different layers up to the skull.
Nevertheless, the resolution can be improved using certain types of filters, or by combining an EEG with another technique or device, such as an fMRI.
However, more electrodes mean a longer period for setup, higher bandwidth for data collection and analysis, and more money for material. Therefore, commercial EEG headsets, available for lower prices to a larger audience, use fewer electrodes because a high spatial resolution is not necessarily needed.
ECoG, or electrocorticography, is a semi-invasive Brain-Computer Interface that uses electrodes placed on the exposed surface of the brain to measure electrical activity from the cerebral cortex.
Although it is semi-invasive, it still requires a craniotomy, a surgical opening of the skull, to implant the electrodes. Thus, ECoG’s are commonly used only when surgery is necessary for medical reasons.
ECoG’s permit for the localization of the cortical region involved in language processing by stimulation, recording, and analyzing the respective brain signals during auditory, language, memory tasks.
The electrodes are placed outside the dura mater (epidural) or under the dura mater (subdural). The strip, or grid, of 4 to 256 electrodes cover a large surface area of the cortex, allowing for a diverse range of cognitive studies.
Unlike EEG’s, ECoG a much high spatial resolution because the signal does not have to travel to reach the scalp. The spatial resolution in an ECoG is within tenths of millimeters, while it can be multiple centimeters in an EEG.
Another advantage of an ECoG over a MEG or EEG is that intracranial recordings are not nearly as susceptible to discrepancies in signals from muscle movements and eye blinks, which often impair the quality of MEG and EEG recordings, especially during speaking and writing.
In addition, ECoG’s are resistant to external noise, provide a lower clinical risk, and have a higher longevity in comparison to other BCI’s. Moreover, the ECoG recordings provide a higher amplitude within the signals collected, making the recordings more precise and easier to analyze.
The most common use of ECoG’s is within epilepsy patients. They are considered the gold standard when it comes to identifying epileptogenic zones in patients. After the patient undergoes a craniotomy, certain parts of the skull are removed and electrodes are surgically implanted.
Invasive Brain-Computer Interfaces, such as intracortical implants, are implanted directly into the brain during neurosurgery. They are either single unit BCI’s, which detect the brain signal from a single area of brain cells, or multiunit BCI’s, which detect brain signals from multiple areas. In addition, the electrodes implanted can have different lengths, often ranging from 1.5 to 10 millimeters.
While invasive BCI’s provide the highest quality of signals, it is procedurally dangerous. The risk of forming scar tissues during the process is high. The brain tissue reacts to the foreign object and builds the scar around the electrodes, causing signal deterioration. Since neurosurgery can be risky, expensive, and potentially problematic, invasive BCIs are mainly catered towards blind and paralyzed patients.
Where Are We Today?
The consumer BCI industry is growing exponentially, with more than a handful of startups and companies launching unbelievably capable and novel products at increasingly affordable prices.
While these new innovations focus primarily on customer applications, these companies are also paying mind to research applications of the technology, growing the field of BCI’s in the process.
“Innovation pushing the boundaries of neural engineering.”
Elon Musk’s Neuralink is currently aiming to offer treatments for brain and nervous system disorders, eventually leading to enhancing normally-functioning brains; for example, increasing memory and processing speed, adding a built-in cloud and internet access, expanding our senses, and telepathic communication.
“Stopping seizures at the source”
NeuroPace was founded to design, develop, manufacture, and market implantable devices for the treatment of neurological disorders with responsive stimulation.
The company’s initial focus is the treatment of epilepsy, and has developed an RNS system that actively monitors the brain’s activity 24 hours a day, recognizes and responds to unique brain patterns to stop seizures, and records brain activity for doctors to review.
“Focus on what matters”
Using EEG sensors, Neurable has collected hundreds of hours of brain-activity to create complex algorithms to understand how the brain handles cognitive load, focus, and distractions.
For focus and EEG data, Neurable measures performance on a specific type of task associates it with brain signals, and builds a model to determine focus with brain signals.
“Measure and leverage brain data at scale”
Emotiv develops an extensive line of hardware and software headsets to be used by doctors and research professionals alike to help improve healthcare.
The company’s wireless EEG headsets can examine stress, focus, and productivity. Their products allow clinicians to build 3D models of the brain to help improve the diagnosis of brain diseases and disorders.
“Everything we are, everything we aspire to become, begins with our brain.”
Kernel is capturing memories from the hippocampus, reading them with AI, and “recording” them with up to 80% accuracy. They are currently accepting applications for their first product, Kernel Flow, which is a non-invasive BCI that records real-time, cortical hemodynamics to establish precise patterns of brain activity.
Beyond these five companies, there are many others making revolutionary strides towards developing accessible and affordable BCI devices. From Neurosity, which develops headsets specifically for coders to maximize productivity, to Muse, which sells affordable headsets for meditation and sleep, there are BCI’s being developed for brain optimization in nearly every aspect of an individual’s day to day life, from sleep, to work, to personal development.
What Is Next For BCI’s?
Brain-Computer Interfaces are revolutionary; and not just because we are connecting the most complex biological thing in the universe to a piece of hardware.
Brain-Computer Interfaces leverage neuroplasticity, the ability of the brain to change, and use operant conditioning to allow the brain to learn and heal on its own. By using the real-time measurement of brain activity, captured within milliseconds, BCI’s provide instant rewards to optimal neural activity, training the brain to maximize the essence of our being.
We are reinforcing the brain to change itself at a subconscious level. In a way that has never been done before.
Not only do BCI’s have a drastic impact on our species at an individual level, but they provide a tangible societal impact. Many researchers believe that the combination of humans and technology could be more powerful than artificial intelligence (AI) alone.
Instead of relying on human perception and reasoning, we can create and use neurotechnologies to improve our perception, as in the case of interpreting a blurry security camera image before deciding whether to take action.
In the future, perhaps the carbon-based mind will connect directly with silicon-based AI, robots, and other minds through BCI technologies to inherently develop the neurological capabilities of our population, while greatly extending our existing senses and even add new ones.
- BCI’s, or brain-computer interfaces, are devices that allow us to convert brain signals into an external output that can replace, restore, enhance, or supplement cognitive function. They establish a direct communication pathway between an enhanced or wired brain and an external device.
- There are 3 different types of BCI’s: non-invasive, semi-invasive, and invasive.
- Non-invasive BCI’s are placed on the scalp, semi-invasive BCI’s are placed on the exposed surface of the brain, and invasive BCI’s are placed inside the brain through neurosurgery. Invasive BCI’s are rarely used and come with the biggest risk.
- The field of BCI’s has been growing over the past few years; beyond Neuralink, we have seen the rise of companies like Kernel, Emotive, Muse, Neurable, Neuropace, and Neurosity, all of which are developing BCI’s for different activities from focus, to sleep, to recording memories.
- While we might not be able to expect telepathy just yet, we are on a trajectory to make unsurmountable progress towards reducing symptoms or even cure diseases like epilepsy, paralysis, and Parkinson’s Disease, as well as allow patients to regain their senses, such as their sight and hearing
Thank you very much for giving this a read! If you learned something from this article, please share it with your friends and family. Be sure to connect with me and/or message me on Linkedin and leave this article a clap 👏 if you enjoyed it!
If you’ve made it this far, I’d highly recommend checking some of these out…
- Wait But Why: Neuralink and the Brain’s Magical Future — and in-depth overview of Neuralink and the future of BCI’s told through stick figures
- HBR: What Brain-Computer Interfaces Could Mean for the Future of Work — Learn about the crazy applications of BCI’s in the workplace…. get ready to have your mind blown.
- The Next 30: The Future of Brain-Computer Interfaces — check out this video for cool analogies and a seven-minute insight into the world of BCI’s!
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