We wanted to hear more about this exciting research and had a conversation with Dr Rylie Green to explore what might current challenges, future opportunities and visions that tell a real story of this work. Dr Green’s research has been focused on developing bioactive conducting polymers for application to medical electrodes, with a specific focus on vision prostheses and cochlear implants. Imperial Tech Foresight spoke to Dr Ryle Green to hear more about the future of living electrodes and the future of the interaction between the biological and the artificial in our bodies.
Could you explain your research on “living electrodes”? Why is your research important?
Traditionally, when we talk about implant devices, we talk about bionic implants, bionic eyes, cochlear devices or deep brain stimulators. Essentially, it is all about electrical interactions that can control nerves and the body reactions to external stimulus. We are finding more conditions that can be treated by electrical interactions. These electric implant devices are helping us to deal with obvious conditions – deafness and blindness – but also others like Parkinson, Epilepsy and ongoing degenerative conditions happening in the nervous system. Over the past 50 years, we have been limited because the technologies we’ve been working with are conventional materials that have been tested over a long time. The materials we use are inorganic and stiff. Often our body is good at recognising them as foreign creating scar tissues around them, which results in an implant that doesn’t do as good a job as it should. For most these devices are aimed to be active across a patient’s lifetime, but most of them fail within a much shorter time span. I work on “living electrodes” which aim to solve this problem, it is made by material that grows together with the nerve and becomes part of it. If we can change materials to react with body and come “alive”, then we will have better control and lifetime guarantee. We are doing this by using everything we have learnt previously from tissue regeneration in terms of stem-cells and scaffolds that we know we can use for tissue repair and integrating them within the bionic devices. We’re hybridising the abiotic it with the biological so that we end up with implants that have better control, better long-term performance and grow into the tissues rather than waiting for the nerves to respond against it and push them away. One of the ways we are doing this is by using materials that are biosynthetic hydrogel materials, such as collagen, which already are produced in the body. We then combine these with a synthetic element to control them.
Where is your research on bionic devices now and where is the field now? What can we do? And, what can’t we do?
Right now, with the living electrodes research, we work on metallic platforms, but we are transitioning to polymer technologies as they have unique benefits. At Imperial College London, we will start in-vivo work. We are bringing together different elements, one of the main ones is trying to control the differentiation of the stem-cells so that they form functional connections with the target tissue. You can form a connection, but you got to form the right synaptic connection. It’s very delicate work, one would block while the other one might activate the nerve. We can see in animal models how this turns out to be very challenging. We are not only developing the technology but also the methods and the techniques to be able to figure out what we’ve done at the same time. We branch in different directions, we are also doing interesting work on active channel microscopy with which we analyse the samples and we are trying to push boundaries in all directions, to try to bring it all back together in a cohesive animal study. Probably, at this stage of our pilot research, we’ll need 12 months before starting to have some pre-clinic trials on rodents.
On a more general outlook, the field has been interesting in itself, I am sure many have heard about the so-called Musk-onian (Elon Musk) propaganda on BMI (Brain Machine Interface) devices. Elon Musk’s Neuro-link has been causing headlines everywhere. None of the technologies he has been using are new, he just brought together different academics who had specific technologies to try get the best of each element. What I find interesting is the specific work around surgical robotics which enable very specific placements of electrodes in the brain. I think that’s the most exciting thing that he has done. All of the electrode technology he works on, essentially is based on conductive polymer electrodes, and many people including myself have been working on those for over 2 decades. We know a lot about them already. I think what he has done for the most part is bringing together the state-of-the-art of these technologies. There is definitely exciting stuff there in terms of bringing together these techniques and making strong investments – and that’s what the field needs, but the field needs also to bring together people in a more transparent way. We are definitely still far from being able to have enough electrodes to interact with the many billions of components the brain is made of.
How do you see your research evolving over the next five years?
There are some really exciting new technologies emerging, as an example we are developing entirely new ways to manufacture devices – such as laser technologies done in partnership with microscopic tech. The next stage will be around cell level connections, where we on a bulk level, with a thousand of cells, can achieve very precise control. The more we can address and control small changes in cells the better products we can build. In epilepsy, you might in this stage being able to control a seizure before it happens. At the moment stimulation is used to stop it, but often nerves are ingenious and move around to the outside to go beyond the control. The individual then still has a seizure. When you control these things on a cellular level, then you get control over the seizure. We will also get the opportunity to learn in detail about how the brain works and how we can stop these things from happening, including the gene regulation of cells.
How do you imagine the way we relate to bionic devices may change as the technology matures, especially around enhancement?
That’s probably what separates our interpretation from the one at Neura-link and from the transhumanists! I don’t think that in the near-future, we will ask to get brain surgery to enhance our cognition. We always have to understand that the reason why we are doing this to treat medical conditions, where cells are behaving in a way that cause a significant impact on the quality of your life. Nobody likes the idea of surgery unless they want to combat something. I don’t see this as a feasible scenario, at least not in a clinical perspective. There are people like the transhumanists that will always be garage technologists, but I don’t think they are going to have access to the right tech to do it well. I am yet to hear of anyone that has been capable of manipulating the brain properly. Most of these actions seem to be limited to placing things under the skin, like people who have the oyster card embedded in their skin. From the skin we can get off signals that are related to what is happening inside our body and use those to control things outside of your body, but it’s all based on wearable technologies that don’t interface directly with our nervous system, they detect neural signals or cardiac signals or muscle signals from the surface. I think that’s where you are going to get that integration of human and computer. Probably we will see such technologies popping up in the next 5 to 10 years.
If you imagine the world in 20 years, what are some of the changes that may be heralded due to your research in the field? What might be different? What may be the same?
We will see technologies rolling out more readily into remote monitoring because they will allow to translate your data immediately for doctors who are not near the patient. That will help tremendously from a monitoring point of view. From a treatment point of view, we are going to see a lot more electrical stimulation. We will definitely see more integration of bionics into humans and move closer and closer to have more bionic parts, we already see people with joint problems, they have pieces replaced such as artificial knees, etc. They turn out to be able to do so many physical activities, running, surfing… We would never have thought that was a possibility 20-30 years ago. We were at a point where our implants were rudimental and would last few years (5-10) as they were used in older adults. As bionics progresses, we are now at a point in which cochlear implants are used for children and are meant to last a long time. These systems can already provide precision in sound detection to sounds that are hardly detectable by a normal hear. You can’t underestimate the impact of the rolling out of such systems in the world. We are not going to see cyborg armies, but we will see the people who do have problems with their neural systems, very happily accepting implants on their systems as they get a benefit from them. To the point in which you will be probably hanging out with a person with tremor disorder and you wouldn’t even know it. We may get to the point where we help people who are paraplegics to walk. In one of our projects, if we can get things right, combining living bionics and regenerative stem cell technology in the spinal cord-packing it the electrodes outside of it, could give us control of the regeneration of the neural synapses and axons and reconstruct those broken connections that could help people walking around again. If that would happen I say I’d be very impressed!
Dr Rylie Green is Reader in Polymer Bioelectronics and joined the Bioengineering department at Imperial College London in 2016. Dr Green’s research has been focused on developing bioactive conducting polymers for application to medical electrodes, with a specific focus on vision prostheses and cochlear implants. Dr Green has ongoing collaborations with a range on industry partners including Galvani Bioelectronics, Boston Scientific and OxSyBio.