Leeds researchers find that stimulating the Vagus nerve with an electric current could rebalance the nervous system and assist in healthier aging.
Ear tickling has finally hit the big time this month, with a University of Leeds team’s discovery that disorders associated with aging may be slowed by applied electrical stimulation of a nerve that terminates at the ear.
The researchers found that a short daily therapy, delivered across a period of two weeks, conferred benefits both to patient well being and physiology, improving quality of life, mood and sleep. The therapy, called transcutaneous vagus nerve stimulation (tVNS), targets one of the three divisions of the central nervous system, restoring it from imbalances that accumulate over time and, potentially, give rise to age-related conditions.
Longevity.Technology: Whether neuro-modulation takes off as a market really depends on if the rebalancing of autonomic conditions is scientifically proven to improve certain conditions. And that depends on the funding that key studies teasing out this connection (like the one here) go on to receive. We’re tipping the Leed’s team’s progress in getting new grants as a key indicator of where the market will go next.
tVNS therapy targets the autonomic nervous system, which controls many of the body’s automatic functions, like digestion, breathing, heart rate and blood pressure. The system is broadly divided between two branches, the sympathetic and parasympathetic, the former assisting in high intensity ‘fight or flight’ mechanisms, and the latter low intensity ‘rest and digest’ activity. Growing imbalances between these two branches, accumulating as we age, are what many scientists believe could contribute to increased susceptibility to disease and the breakdown of bodily function.
It is for this reason that research has focused on the vagus nerve, which has attracted a lot of clinical interest from those looking for therapies for disorders as wide-ranging as depression, epilepsy, obesity, stroke, tinnitus and heart conditions. The nerve is the major nerve of the parasympathetic system, connecting the brain stem to the major organs of the body.
It was in a previous study that the Leeds team affirmed the nerve could successfully be stimulated at key points on the outer ear (without need for invasive surgery to implant electrodes) and that this electrical stimulation successfully improved the balance of the parasympathetic nervous system with the sympathetic in healthy 30 year olds. Now, as their Aging [1] paper shows, they have been able to replicate this rebalancing act in those aged 55 and above. After exposing patients to 15 minutes of tVNS therapy over a period of two weeks, results showed a realignment of the two nervous system branches, with subjects saying they felt improvements to their mental health and sleeping patterns.
The researchers made the tVNS system themselves, using a TENS (transcutaneous electrical nerve stimulation) device.
But does positive patient feedback really indicate that nervous system rebalancing is linked to healthier aging? Or is this simply a placebo? The researchers see this as the question their next research should answer. Dr. Jim Deuchars, one of the study’s lead authors, is optimistic about his team’s prospects.“We don’t know if it’s causative. The imbalance could be a response to other disorders occurring in the body,” He told Longevity.Technology. “What we do know is, taking heart failure for example, the sympathetic nervous system increases in influence and that drives the progression of heart failure. So one treatment of heart failure is to dampen the sympathetic nervous system.” Which is exactly what tVNS does.
He continues: “We’ve published a 2014 study on normal subjects, and some people in the US with Crohn’s Disease have tried the method and seen that it seems to have helped. We’d like to do a proper study on this. People are also trying it for sleep, and for general wellness. A good one to look into would also be heart failure.”
Once the team acquire funding they hope to do begin pilot studies testing their therapy’s ability to tickle improvement into patients suffering from these conditions.
The news comes at an interesting time, our understanding of how the nervous system works and how we can develop therapies for it is very recent, but researchers and companies are steaming ahead with breakthroughs and innovations in multiple areas of investigation. Elon Musk’s Neuralink springs immediately to mind as the most bombastic example, but there are also more immediate applications – like those being pursued by the UK-based Bios, who are pursuing AI methods for interpreting and transmitting nerve signals, with applications for bionic limbs and early disease detection.
Bios founder and director Emil Hewage told Longevity.Technology [LINK]that now they have the data about how nervous systems work, “We can spend the next couple of years prototyping really advanced autonomic treatment. We call it ‘neuroceuticals’: basically, replacing a drug with an algorithm that can be delivered neurally.”
The Leeds University team’s therapy fits very neatly into this space, but on whether his work will be looked back upon as one of the first signs of a paradigm shift in treatment towards ‘neuroceuticals’, Dr. Deuchers advises a cautious approach. “I think neuro-modulation is a burgeoning market. People are only now coming to an understanding, along with providing evidence, that it actually produces a biological effect,” he told us. “There’s an increasing scientific interest. Whether it’s a cure or just an adjunctive improvement is difficult to determine.”
[1] https://www.ncbi.nlm.nih.gov/pubmed/31358702
