Please note - a new method known as optogenetics will enable applications that were previously impossible, for example the ability for the nearly blind to see reasonably and the deaf to even hear music
Patrick Degnar, University of Newcastle
The nervous system that commands the body and controls it is a wonderful structure, but sometimes things can go wrong. Defects in our DNA can cause a variety of disorders. Accidents, old age and even poor nutrition can equally cause the destruction of the nervous system. Medicines and treatments may help but in many cases there is no treatment and even if there is, treatment for neurological disorders is less effective than for other diseases.
There are treatments that have been performed for thousands of years, for example electrical stimulation of the nervous system. Doctors in ancient Rome used electric eels to provide shock therapy for mild pain. Almost 2000 years later we use a similar electrical technique using TENS (Subcutaneous Electrical Nerve Stimulation) devices.
Advanced treatments today include the use of neuroprosthetic devices that directly link electronic systems with the nervous system to replace damaged functions. These are pacemakers and sensory prostheses that replace the senses of sight and hearing for the blind and deaf. Nearby technologies may even penetrate the autonomic nervous system to treat a variety of chronic diseases such as diabetes.
There are pacemakers today that not only provide electrical stimulation but are also wired into the autonomic nervous system to understand our unconscious emotions.
Pacemakers operating in a closed circuit stimulation method and defibrillators use this method to speed up the heart rate when the patient experiences emotions such as anxiety and excitement, thus allowing the patient to enjoy horror movies and function in important meetings.
seeing the light
Visual prostheses for the blind have the potential to change lives even more. After many decades of development, today there are devices that can be wirelessly connected to a chip in the eye connected to a camera system and processing systems. For people suffering from retinitis pigmentosa, a disease that causes the light-sensitive retinal cells in the eyes to gradually die, these devices transmit visual information to the remaining retinal cells through electrical stimulation. However, so far, they can only reproduce a raw image that looks like a handful of blinking dots.
The neuroprosthetics revolution has the potential to reach further, and unlike many innovations in this field, which come from developments in the field of electronics, this development actually comes from biological research.
In 2003, German scientists studying algae discovered a protein that can turn nerve cells into light-sensitive cells. This led to a new method known as optogenetics, which involves gene therapy designed to make the cells in the eye sensitive to light. This new technique is significantly more powerful and accurate than previous techniques and maintains high-resolution communication with the nervous system.
In the case of retinitis pigmentosa, instead of replacing the retina with cells with a chip, optogenetics allows us to restore the ability to detect light in the remaining cells, first using special electronic glasses and then they can be used to transmit optical information in a way that these new sensitive cells can understand.
The first human patients were recently treated with the gene therapy technique in the USA. If the method works as planned, there will be a real revolution in the quality of patients' lives. There are groups of researchers who claim that it will almost be possible to restore normal vision. Other groups, including mine are a little more cautious but they believe that in the medium term it will allow patients to walk without a cane, and maybe even recognize faces again. We also hope to be able to adapt the technique to a larger group of patients including those suffering from blinding glaucoma and trauma.
Similar progress, it is hoped, will also come in the field of hearing implants which today can allow patients to join small group conversations but every music sounds to them like Death Metal performed underwater. American and German teams hope to use optogenetics as a more precise way to stimulate auditory nerve cells than conventional electrical implants. They hope that this way it will be possible to produce devices that will allow listening to music almost normally.
Conversations with the mind
Optogenetics also has the potential to treat tens of millions of patients with epilepsy and other brain disorders. Part of the problem with traditional neuroprosthetic systems is that it is difficult to stimulate the nervous system and receive nerve electricity at the same time. It's like hearing someone whisper when another shouts, but using optogenetics, the nerve can be stimulated with light without affecting the electrical signals. This means that it will now be possible to have a conversation directly with the brain.
In order to successfully apply the technology to epilepsy patients, we intend to send signals to the parts of the brain that oversee behaviors such as perception and ask them to relax. We hope to be one of the first teams to try the method on an epilepsy patient in 2021. If it works, it will change the lives of patients who have had to use drugs until now.
In the coming decades we will see neuroprosthetics combined with genetic therapies such as optogenetics, and perhaps even stem cell therapies.
Even traditional pharmaceutical companies are beginning to explore the possibilities of developing bioelectronic drugs with the goal of stimulating the body's own organs to produce therapeutic biochemicals. This method has the advantage that it will allow doctors personal treatment and at least improve the conditions of certainty.
For those who grew up on movies like Blade Runner, one would expect that all humans today would have enhanced themselves by adding bionic implants. In reality we are still far from this vision of the future. On the other hand, science fiction writers are just beginning to close the gap with the reality of biology-enriched bionics. In the end, it is difficult to overcome nature, but if we can bring almost normal functions to people with disabilities, this could significantly improve their lives.
More of the topic in Hayadan:
- to hack the nervous system
- An artificial neuron that mimics a human neuron
- "In the future hackers will penetrate our brains"
Translation: Avi Blizovsky
