Brain Implants Made of Graphene - What is Possible?

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By Angela Betsaida B. Laguipo, BSN, RN

Technological advancement shows promise in various disciplines, including in the world of medicine. Over the past few years, humans have developed advanced technologies that contributed to breakthroughs improving the quality of life and performance of humans. One of these innovations is the development of the brain implant.

What are Brain Implants?

Brain implants, or neural implants, are devices directly connected to the human brain, usually on its surface. These devices are used to help patients with brain disorders by electrically stimulating, recording or blocking signals from neurons in the brain.

How Do Brain Implants Work?

Brain implants can be used in a variety of applications. These are technical systems mainly used to stimulate some parts of the brain or nervous system. As a result, the device boosts senses, memory or physical movement. They are usually used to replace damaged tissue or part of the brain.

A brain implant restores cognitive function by gathering data from one brain area, processing the information and delivering the resulting signal to another region of the brain.

Brain Implant Applications

Depression

Doctors have developed many different ways to treat depression; however, for patients who haven’t responded to treatments, deep brain stimulation (DBS), or sending electrical shocks directly to some brain areas, is recommended.

Though this method is promising, it has shown many inconsistencies. However, a new study from scientists at the University of California, San Francisco proposes the use of brain implants or electrodes. These will be attached to the lateral portion of the orbitofrontal cortex (OFC), which is an area for decision making, mood regulation and emotion processing. This area has also been linked to the development of depression.

Parkinson’ Disease

In another study, self-tuning brain implants could help treat patients with Parkinson’s disease. Researchers found that stimulating electrodes can provide deep brain stimulation (DBS) to reduce the symptoms of the neurodegenerative disease. The implant is connected to a small computer under the skin and the data is analyzed by an external device.

Memory Booster

Brain implants may help boost memory, which can help patients suffering from Alzheimer’s disease. A study has shown that brain implants that send electrical signals into the brain can help restore memory function in humans.

Brain Implant Material Issues

It has been a challenge to find the right material for use in brain implants. There is a fundamental asymmetry between the devices and the brain. For instance, smartphones and computers use electrons that are passed back and forth, whereas neurons use ions like potassium and sodium.

Another issue when it comes to determining a good material for brain implants is mechanics. Today, many use silicon-based technologies in brain implants. At first, they work very well, but in the long run they start to fail. The brain may also experience micro-motion artifacts or the small movements of the probe in the brain. This can cause inflammation, tissue damage and exacerbate scarring. Though these are just natural biological reactions, they can lead to failing signal quality, and eventually, the implant fails.

Brain Implants Made of Graphene

A promising new material to use in brain implants is graphene. Graphene is a super-thin carbon material that has shown promise in many areas of science and technology.

In a new study conducted by scientists at the Cambridge Graphene Centre, it was found that graphene can be utilized to create highly-effective and flexible brain implants. Graphene brain implants are used to prevent the loss of signal problem linked to scar tissue forming around modern electrodes made from hard substances, including tungsten and silicon.

Since the brain is made of soft tissue, the brain implant should also be flexible. Graphene can help make implants with excellent biocompatibility properties.

Another study shows that a graphene-based brain implant can record electrical activity in the brain. The implant utilizes a transistor-based architecture that can amplify the brain’s signals in situ before transferring them to the receiver. Using graphene can help support more recording sites than a regular electrode array.

Furthermore, graphene is flexible, slim and thin. Hence, it can be used over large areas of the cortex without the risk of rejection or interference with normal brain function. In the future, graphene brain implants will be capable of detecting even the slightest brain activity known to carry vital information about various events, such as the onset and progression of strokes. These implants will not only detect possible strokes, but also determine where and how seizures start and end, enabling new treatments and approaches in treating epilepsy.

Sources and Further Reading

Rao, V., Sellers, K., Wallace, D., Shanechi, M., Dawes, H., & Chang, Edward. (2018). Direct Electrical Stimulation of Lateral Orbitofrontal Cortex Acutely Improves Mood in Individuals with Symptoms of Depression. Current Biology. https://www.cell.com/current-biology/fulltext/S0960-9822(18)31355-1

National Institutes of Health. (2018). https://www.nih.gov/news-events/news-releases/self-tuning-brain-implant-could-help-treat-patients-parkinsons-disease

Hampson, R., Song, D., Robinson, B., Fetterhoff, D., Dakos, A., Roeder, B., She, X., Wicks, R., Witcher, M., Couture, D., Laxton, A., Munger-Clary, H., Popli, G., Sollman, M., Whitlow, C., Marmarelis, V., Berger, T., & Deadwyler, S.(2018). Developing a hippocampal neural prosthetic to facilitate human memory encoding and recall. Journal of Neural Engineering. https://iopscience.iop.org/article/10.1088/1741-2552/aaaed7/meta

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Masvidal-Codina, E., Illa, X., Dasilva, M., Calia, A.B., Dragojevic, T., Vidal-Rosas, E., Prats-Alfonso, E., Martinez-Aguilar, J., De la Cruz, J., Garcia-Cortagela, R., Godignon, P., Rius, G., Camassa, A., Del Corro, E., Bousquet, J., Hebert, C., Durduran, T., Villa, R., Sanchez-Vives, M., Garrido, J., & Guinera-Brunet, A. (2019). High-resolution mapping of infraslow cortical brain activity enabled by graphene microtransistors. Nature Materials. https://www.nature.com/articles/s41563-018-0249-4