An Introduction to Neuroprosthesis and BCIs

by Rowan Whitney

We have all heard of Sci-Fi flicks where people get chips implanted into their brains to augment their capabilities, which may seem far off by today’s standards. This trope of science fiction, however, is already presenting itself as a reality. These “brain chips”, or in more scientific terms, neuroprosthetic implants or brain-computer interfaces (BCIs), are helping people with disabilities today, and in some cases, have been for decades. The future looks strong for the development of neural interfaces, so let’s take a look at several examples of neuroprosthetics that currently exist and are in the process of research and development.

We know some BCIs better as cochlear implants, retinal implants, and neurostimulators, which were devised to help with deficiencies in hearing, vision, and various mental conditions (Parkinson’s, epilepsy, chronic pain, clinical depression, and more) respectively. Neurostimulation, more specifically vagus nerve stimulation, has been in use since 1997 (Amin, 2018). The first single channel cochlear implants were released in 1972 (Brown, 2003). These dates tell us that devices connecting to the nervous system (brain-computer interfaces) have been in practice for decades, the first released being the cochlear implant, which was introduced a full half-century ago.

There are really only three functions of brain-computer interfaces: to stimulate, to record, and to block.

Here is a more in-depth delineation: 1) stimulating devices, which provide the nervous system with stimulating voltage pulses or other feedback, such as with neurostimulation) 2) recording devices, which serve mainly as observational tools for scientists (namely electrodes, electroencephalographs (EEGs), and Functional Magnetic Resonance Imaging (FMRI) machines, which afford a view of the activity of desired regions of a subject’s brain), and 3) blocking devices, which block certain stimuli or activity from occurring. (Anderson, 2008)

These devices are not cheap, however. Starting on the “affordable” side, cochlear implants in the United States, at least, are usually covered by various forms of healthcare. Retinal implants are more costly, with the Argus II Artificial Retina or “bionic eye” reaching $150,000 USD in cost, not including the cost of surgery and rehabilitation (Duffy, 2013). What’s more, these “sensory substitution” implants are only those that are available for purchase, leaving the prices of more complex, as yet commercially unavailable devices completely open to speculation. An example of a developing neuroprosthetic system is the osseointegrated (bone-anchored) prosthetic arm devised by Max Ortiz-Catalan et al. which interfaces directly with the nervous system, meaning that users can control the limb via thought, and can directly feel stimuli applied to it. (Catalan et al., 2014) It is reasonable to think that systems advancing in that direction, upon public release, garner high demand.

Now that we’re familiar with BCIs, let’s discuss their potential applications. Sensory substitution BCIs such as the implants discussed above are the first line of applications. In parallel, neurostimulators are and will continue to be used throughout the world of medicine. Next are the “bionic limbs”, or prosthetics in the same vein as that discussed in the article by Catalan et al., whose further development centers around providing more realistic and higher quality limb prosthetics. Further, labs have started developing systems to connect paralyzed patient’s brains to external prosthetic limbs, to enable them to perform movements and receive haptic feedback. (Hochberg et al., 2014) This has the potential to assist patients suffering from “locked-in” syndrome, a condition where nerve damage renders the body disconnected from the mind operating it, even though the person is fully aware of their surroundings.

Some out there might have guessed that DARPA might find its way onto this list, and rightly so.

DARPA is widely known for attempting some… unusual research. One of their projects on the weirder side has been the Hybrid Insect Micro-Electro-Mechanical Systems (HI-MEMS) program. Simply put, this program successfully integrated BCIs into the brains of juvenile cockroaches, allowing researchers to control their movements. (Anthes, 2013) Even more DARPA-esque, a little known project from the early 2000s attempted to remotely control the movements of sharks via BCIs to act as naval reconnaissance. (Highfield, 2006) Unlimited are the possibilities.

We are not DARPA. At the Carboncopies Foundation, BCIs serve to illustrate a part of the research and development we strive to promote. Every neuroprosthetic, from cochlear and retinal implants to bionic limbs and remote-controlled animals, has enabled us to understand more about brains, human and otherwise, and how to interface with them. The mission of the Carboncopies Foundation is to preserve, restore, and even improve your mental experience beyond the limits of biology. To accomplish this, it is essential to first understand the brain and the symphony of its workings. Neuroprosthetics is a fast developing field, and advances within it bring us one step closer to that understanding.

Keywords: Retinal implants, cochlear implants, brain-computer interface, neurostimulator, neuroprosthetic implants

Updated 1/21/22

References

Amin, U. (2018, July 02). Neurostimulation for the Treatment of Epilepsy. Retrieved January 01, 2019, from https://emedicine.medscape.com/article/1186123-overview

Anderson, P. (2008, July 09). Implantable Device that Blocks Brain Signals Shows Promise in Obesity. Retrieved January 01, 2019, from https://www.medscape.com/viewarticle/577292

Anthes, E. (2013, February 17). The race to create ‘insect cyborgs’. Retrieved January 20, 2019, from https://www.theguardian.com/science/2013/feb/17/race-to-create-insect-cyborgs

Duffy, M. (2013, August 19). The Argus II Retinal Prosthesis (“Bionic Eye”) Receives Medicare Approval. Retrieved January 01, 2019, from https://www.visionaware.org/blog/visionaware-blog/the-argus-ii-retinal-prosthesis-bionic-eye-receives-medicare-approval/12

Herreros_alonso I, Giovannucci A, Taub AH, Hogri R, Magal A, Bamford SA, Prueckl R and Verschure PF(2014) A cerebellar neuroprosthetic system: computational architecture and in vivo experiments. Front. Bioeng. Biotechnol. 2:14. doi:10.3389/fbioe.2014.00014 http://www.sim.me.uk/neural/JournalArticles/HerrerosEtAl2014.pdf

Hochberg, L. R., Bacher, D., Jarosiewicz, B., Masse, N. Y., Simeral, J. D., Vogel, J., Haddadin, S., Liu, J., Cash, S. S., van der Smagt, P., … Donoghue, J. P. (2012). Reach and grasp by people with tetraplegia using a neurally controlled robotic arm. Nature, 485(7398), 372-5. doi:10.1038/nature11076 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3640850/

Mahoney, P. (2007, June 21). Wireless is getting under our skin. Retrieved January 01, 2019, from https://web.archive.org/web/20080604164839/http://machinedesign.com/ContentItem/67966/Wirelessisgettingunderourskin.aspx

Ortiz-Catalan, M., Håkansson, B., & Brånemark, R. (2014, October 08). An osseointegrated human-machine gateway for long-term sensory feedback and motor control of artificial limbs. Retrieved January 17, 2019, from http://stm.sciencemag.org/content/6/257/257re6

Highfield, R. (2006, March 02). Sharks are Pentagon’s latest spy recruits. Retrieved January 27, 2019, from https://www.telegraph.co.uk/news/science/science-news/3345150/Sharks-are-Pentagons-latest-spy-recruits.html

Brown, C., Geers, A., Hermann, B., Iler Kirk, K., Tomblin, B., Waltzman, S. (2003, March) ASHA Technical Report, Working Group on Cochlear Implants. Retrieved January 21, 2022, from https://www.asha.org/policy/tr2004-00041/#:~:text=The%20first%20single%20channel%20cochlear,1980s%20including%20several%20hundred%20children.