Cyborgs are no longer science fiction. The field of brain-machine interfaces (BMI) – which use electrodes, often implanted into the brain, to translate neuronal information into commands capable of controlling external systems such as a computer or robotic arm – have actually been around for some time. Entrepreneur Elon Musk’s company, Neuralink, is aiming to test their BMI systems on a human patient by the end of 2020.

In the long term, BMI devices may help monitor and treat symptoms of neurological disorders and control artificial limbs. But they could also provide a blueprint to design artificial intelligence and even enable direct brain-to-brain communication. However, for the time being, the main challenge is to develop BMIs that avoid damaging brain tissue and cells during implantation and operation.

BMIs have been around for over a decade, helping people who have lost the ability to control their limbs, for example. However, conventional implants – often made of silicon – are orders of magnitude stiffer than the actual brain tissue, which leads to unstable recordings and damage to surrounding brain tissue.

They can also lead to an immune response in which the brain rejects the implant. This is because our human brain is like a guarded fortress, and the neuroimmune system -– like soldiers in this closed fortress – will protect neurons (brain cells) from intruders, such as pathogens or BMI.

Flexible devices

To avoid damage and immune responses, researchers are increasingly focusing on the development of so-called “flexible BMI”. These are much softer than silicon implants and similar to actual brain tissue.