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Roula Khalaf, Editor of the FT, selects her favourite stories in this weekly newsletter.
Yes
“Vagus” is a Latin word meaning “wandering”, and the nerves with that name (one on the right, one on the left) meander around the body, connecting the brain to the heart, the lungs, the gut and beyond. They’re known to play a significant role in putting us in a state of rest and digest (as opposed to fight or flight), and studies have shown that vagus nerve stimulation (VNS) can calm and regulate some bodily functions. (The potential cardiac side effects of stimulating the right means that VNS concentrates almost exclusively on the left.)
I started to feel I had more energy just after the first week
Yōjō user Andrea
Most notably, VNS implants have long been used by doctors to treat epilepsy. But the vagus nerve can also be stimulated via the skin, usually in or around the left ear, using small electrical pulses that give a tingling sensation. A number of devices on the market claim to do this safely, and some have been shown to have positive effects for specific conditions. One, GammaCore, is available on the NHS to treat cluster headaches via neck-based VNS. Another, made by German firm tVNS Technologies, is being used in a £2mn study (Triceps) at Sheffield University into treating arm weakness following a stroke, funded by the NIHR Efficacy and Mechanism Evaluation board, the Association of British Neurologists and the Stroke Association.
Yōjō vagus stimulation device and subscription, £399 per year
Manufacturers indicate that the nerve’s size means that stimulating it could have wider beneficial effects relating to fatigue, digestive disorders and more. Parasym, makers of a device called Nurosym, has published more than 50 clinical studies including one showing a 32 per cent improvement in memory. Anecdotal evidence, meanwhile, is rich. “My energy levels have been such an obvious difference,” says Andrea, COO of a medical education company, who uses a device called Yōjō to treat chronic migraines. “I started to feel like I had more energy just after the first week.”
No
The word “vague” comes from the same Latin word, and could be used to describe some of the feelgood claims made for VNS devices. While users have credited them with improving sleep patterns, symptoms of IBS and much else, the reasons are not properly understood. “It might improve someone’s mental health, and if it works for them then who am I to argue, but as a doctor I can’t prescribe it,” says Professor Arshad Majid, chief investigator of the Triceps trial.
TVNS E with Legacy Electrode
Price: €3,500
BUY
Nurosym
Price: £599
BUY
“To be able to understand which device is better, we would need some sort of signal of efficacy to measure,” he continues. For its part, Yōjō pairs with an app that does a face scan via your phone’s camera to estimate blood pressure, HRV and pulse, with the aim of building up a picture of said efficacy – but in my own tests its estimation of my blood pressure was rather different to readings from a cuff.
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“Stimulating the vagus nerve pathway via the ear is biologically plausible, but there are many questions left to answer – which stimulation settings? When? For how long?” says Tiago da Silva Costa, senior research fellow in Psychiatry at Newcastle University. His colleague, Hamish McAllister-Williams, professor of affective disorders at the same institution, agrees. “I think that the main benefit that people get from some devices may be more of a placebo response. But they are probably safe, probably do not harm and may at least get people to relax for periods of the day.”
