Brain Computer Interfaces: The What, The How, The Why

When I was little, my teachers, friends, camp counselors would always ask the same question: if you could have any superpower, what would it be? I would always say telekinesis or telepathy. I always wanted to be able to move things with my mind or know what other people are thinking. As a seven-year-old, that entire concept seems entirely made-up. However, with the power of Brain-Computer Interfaces, it might not be as supernatural as you might think.

What Are Brain-Computer Interfaces?

Essentially, a Brain-Computer Interface, or BCI, is a technological way to create a direct communication pathway between the brain and an external device. BCIs work by interpreting different signals’ output by the brain, each representing a different physical action. They can control machinery, operate computers, and even communicate with others telepathically.

How Does This Work On a Scientific Level?

The brain controls everything that we feel, say, and think. It is made up of billions of neurons, each of which transmits information to other neurons, nerves, muscle, or gland cells through chemical signals called neurotransmitters. The neurotransmitters also translate to electrical activity, which can then be recorded and interpreted. However, not every neuron does the same thing. Instead, the brain is separated into regions that specialize in different things such as motor skills, language skills, consciousness, etc. Therefore, neurons in a specific region will emit cohesive signals when active.

But How Does This Translate To Computers?

Three main kinds of BCIs are currently in use. Electroencephalography, electrocorticography, and neural dust. Some are invasive, and others are not.

ELECTROENCEPHALOGRAPHY (EEG)

EEGs are used to measure the electrical activity emitted by the brain’s neurons. EEG uses external electrodes placed on the scalp, not to detect individual neurons’ activity but that of a group of active neurons simultaneously. EEGs specifically measure postsynaptic potentials and changes in the neurons’ polarization of the electrical activity. For the most part, postsynaptic potentials are based on the brain’s chemical reaction to mental and physical impulses. The majority of EEG powered BCIs will look like electric caps so that the electrodes can record as much of the brain’s activity as possible.

Present Implementations of EEGs

As of now, EEGs are being used for a wide variety of projects and experiments. EEGs are being used for new kinds of prosthetic limbs, which users can use just like a normal arm or leg. EEGs are also being used to control computers and communicate with others telepathically. Companies such as Muse and NextMind produce commercially available BCIs that use EEGs or something very similar to allow consumers to use BCIs in their own homes.

ELECTROCORTICOGRAPHY (ECoG)

ECoG is a kind of BCI that utilizes direct contact between the brain and the machinery. In this case, ECoG entails placing a sheet of electrodes on the brain itself to record postsynaptic potentials instead of from the scalp. While this method is invasive, it tends to record better quality signals than EEG. Like EEG, the ECoG will translate the signals, each representing a different mental or physical action, from the brain to a computer, where they can initiate actions or be relayed onto another person.

Present Implementations of ECoGs

One of the perks of using ECoG, besides the better readings, is the ability to send signals into the brain. ECoGs are used a lot like EEGs except that they require much more equipment and have more risks (seeing that you are essentially peeling off the skull and putting things onto the brain). ECoGs are typically used to record data and monitor brain activity. However, recent breakthroughs in tandem with AI have used ECoGs to translate brain waves into text.

IMPLANTS

The last major category of BCIs is implants. This involves multiple subcategories, but is anything that is placed into the skull and is sealed in.

Present Implementations of Implants

A major subcategory is called Neural Dust. The main defining characteristic about neural dust is that it is extraordinarily small, hence neural dust. It is about as small as a grain of sand. Engineers first created the wireless sensor at UC Berkeley in 2016. It gets implanted into the brain’s nerve cells and records its electrical activity. The neural dust readings can also be transmitted using ultrasound to external facilities to be analyzed. Neural dust is another device that focuses on recording data a little bit like a tiny internal Fitbit. However, while simply recording data doesn’t seem all that important, it is. Amputees can use signals in nerves for arms or legs to control prosthetics, especially fine motor skills in the hands and feet.

Another kind of implant is Neuralink. It is a company run by Elon Musk that strives to use BCIs to solve neural and spinal problems. They use robots to perform the implantation because it is too intricate to be done by a person. The device is also implanted into the skull and is completely inconspicuous.

The last major company using implants called NeuroPace is using implants to help people with epilepsy. Epileptic seizures usually stem from unusual activity in the brain. NeuroPace has essentially created a device that is placed directly into the skull, which may sound very dangerous, but is not. It will analyze the signals coming from the brain. When it senses the seizure causing signals, it will automatically emit micro pulses to counteract the seizure before it starts, without the user’s knowledge. Otherwise, the device is entirely passive.

Future technology

In the future, BCI specialists are focusing on a variety of things for BCI. As the years progress, all BCIs will continue to get smaller like neural dust. And instead of just collecting data, many companies are focusing on also emitting signals and pulses into the body. Neural dust companies are focusing on using neural dust in more than just the brain. They hope that it can be implemented onto nerves throughout the body. They hope to use it for monitoring organ health, suppressing appetite, controlling bladder function, and treating epilepsy. As for the future of EEGs, specialists are hoping to use it with biometrics to avoid the hacking of fingerprint, voice, iris, etc. recognition based security systems. EEGs have been proven to identify biometric data just through their electrodes.

Final Thoughts

We have this amazing technology at our disposal, technology that can record our brain’s activity, power robotic prosthetic limbs, and even cure epilepsy. Later down the road, this technology can monitor our organs’ health and fortify biometric-based security. Curing epilepsy and lowering death rates by heart attacks is groundbreaking, but not everything surrounding BCIs can be as impressive. With the addition of the internet, people could find people’s credit card numbers and phone numbers so much easier. But when that happens, there are things that you can do about it. However, getting a new brain or fingerprint or iris is something you can’t get another of. Nevertheless, the truth is that BCIs won’t solve every problem, but they can solve some.

Thanks for taking the time to read my article. I hope you enjoyed it!

I am a 15 year old in high school with a passion for brain computer interfaces. In the future, I hope to write more about my adventures learning about this emerging technology.

Make sure to reach out to me with any comment, questions, or concerns at caitlinkim2024@gmail.com or on my LinkedIn.