Neuroprosthetics: Brain Interface Applied in Neurology
The brain is the fattiest organ in your body made up of 60% fat, the dry part that is. 75% of your brain is actually water which houses 100,000 miles of blood vessels that use up 20% of all your oxygen and blood. It’s an amazing piece of hardware. Of all the moonshot projects out there, the ones that relate to augmenting the brain are perhaps the most fascinating. Companies like Kernel have actually succeeded in writing long-term memories to a chip – well, at least 80% of them. When that number hits 100%, the sky is the limit to what we can do with the brain.
If you want a graphic image of what the future holds, imagine a robotic arm on top of your table (no wires) moving its fingers or trying to grab something powered only by someone’s thought. After all those Terminator movies, this could be a bit creepy. You may not get Terminator at your doorstep just yet, but someone with neuroprosthesis might just be ringing your doorbell a few years from now.
Neuroprosthetics or neuroprosthesis is a field of biomedical engineering and neuroscience concerned with the development of neural prostheses which are a series of devices that can substitute your brain’s motor, sensory or cognitive functionality that might have been damaged as a result of an injury or a disease.
We discussed before the topic of a brain-computer interface that serves to connect the brain to a computer. In this case, we want to develop a device to replace a missing biological function. Obviously, before we can do that, we need to be able to communicate with the brain. What do the regulatory authorities think about this sort of futuristic vision? In a workshop posted by the United States Food and Drug Administration (FDA), neuroprosthesis was defined as being synonymous with a brain-computer interface (BCI):
Neuroprosthesis: A device that interfaces with the central or peripheral nervous system to restore lost motor or sensory capabilities.
The definition has inadvertently classified all brain-computer interfaces as neuroprosthesis. Then again, this is just a discussion paper in aid of regulation. (It might be of some comfort that the Terminator hands that will grab your neck in some apocalyptic future are US FDA Approved.) When you explore this field in neurology, you will come across robotic prosthesis. This is still neuroprosthesis but more specifically applied to robotic limbs like arms.
The brain’s interaction with any device is dependent on two things:
- The predictable patterns or frequency indicating brain activity; and
- The signal processing happening when the brain interface captures the signal from the brain or interprets the brain’s activity.
The system of hardware and software that processes the signals or brain waves emitted by our brain and the subsequent translation of these signals into digital data is what constitutes the platform of the brain interface. This is what Kernel is working on. That same platform can be used for neuroprosthesis.
Understanding & Mapping Brain Activity
As we discussed in our last article on brain-computer interfaces, our understanding of brainwave and brain activity started when scientists discovered electroencephalography or EEG. This technology led to more understanding of brain activity that eventually became a favorite device for neurofeedback or biofeedback in psychotherapy.
When digital technology became cheaper, it was easier to map brain activity using neuroimaging which lets us see what is happening to the brain as we react or execute certain motor functions. We can now see it in “living color” on a computer monitor. Using this additional data, researchers concluded that certain stimuli or certain activities represent different levels of intensity in different areas of the brain. They started with the movement of the eye, then upper limbs and then a series of other experiments to “map” the functions of the brain.
This accumulated data or maps of the brain became a sort of dictionary for innovators to equate certain signals to certain actions which we now see as movements in robotic arms or display of text on a computer monitor when a test subject “thinks” about a word or a movement.
Interpreting and Translating the Brain’s Language
There are currently two ways to capture and to interpret brain activity:
- Capturing certain patterns of brain activity and then translating it; or
- Capturing the myoelectric signal coming from the brain traveling to the nerves that activate certain muscle groups, in most cases, muscle around our arms.
The most common approach in neuroprosthesis currently available for those with upper limb disabilities is the use of the myoelectric signal. This technology is already being used to support the needs of persons with amputated upper limbs. Physical injuries that are localized to upper limbs tend to leave the nerves connecting the brain to the bone muscles usually intact. This is the connection that is required to fire off myoelectric signals to the robotic prosthesis.
A company called MYOMO in Cambridge, Massachusetts is already deep into this technology and enabling individuals to regain the ability to use arms and hands for feeding, lifting, and reaching. Investors should take note that MYOMO is currently testing the water for an IPO and is gauging investor interest at the moment.
The next step in neuroprosthesis is to enable certain movement of the robotic prosthesis by simply thinking of the intended action. The brain interface for this technology reads the brain’s intent to execute a movement and the interface sends a signal that will stimulate the right robotic movement to execute.
BrainRobotics, a company founded by Bicheng Han in 2015, was established to develop a brain interface as a driver for the robotic prosthesis. The company is considered a great combination of cutting-edge technology and corporate social responsibility. They offer robotic prosthesis at a price range below $3,000 per kit. This is in keeping with their team slogan: “Anyone who needs it can afford it and improve their quality of life”.
Neuroprosthetics is not limited to the robotic prosthesis. It is actually a technology with many market niches which include auditory and retinal implants. These technologies can become a reality when we have the ability to directly receive signals from the brain and interpret them to execute desired movements or actions.
Allied Market Research estimates that revenues from neuroprosthesis products will hit $14 billion by 2020. The driver of the demand for neuroprosthetics is a result of the lack of preference for drugs as a primary intervention and invasive surgeries as a secondary intervention by 80% of patients.
In the coming weeks, we will be posting a follow-up article about companies actively developing and marketing the next generation of prosthesis. Make sure you sign up for our newsletter so you don’t miss out.
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