Nick Carne
“Tickling” the ear with a small electrical current appears to rebalance the autonomic nervous system in older people, potentially slowing down one of the effects of ageing, a small UK study suggests.
The therapy, known as transcutaneous vagus nerve stimulation (tVNS), is used to treat clinical disorders such as epilepsy, and studies have investigated its potential in relation to everything from heart disease to tinnitus, migraines and the extinction of prepared fear.
Previous work at the University of Leeds has shown that applying an electrical stimulus to the vagus nerve at the ear improves the balance of the autonomic nervous system in healthy 30-year-olds.
In the latest study, a team led by Beatrice Bretherton wanted to see whether it could benefit over 55-year-olds, who, they say, are more likely to have out-of-balance autonomic systems that could contribute to health issues associated with ageing.
They taught 29 healthy volunteers to self-administer tVNS therapy for 15 minutes a day, for two weeks, and found that this led to an increase in parasympathetic activity and a decrease in sympathetic activity – essentially rebalancing the autonomic function towards that associated with healthy function.
Some participants also reported improvements in measures of mental health, mood, sleeping patterns and quality of life.
Significantly, the researchers found that people who had displayed the greatest imbalance at the start of the study showed the most improvement.
They suggest that in future it may be possible to identify who is most likely to benefit from the therapy, so it can be offered through a targeted approach.
They acknowledge that it was a small and short study, but are nonetheless confident in the findings and planning further studies to see if tVNS can benefit multiple disorders.
“The ear is like a gateway through which we can tinker with the body’s metabolic balance, without the need for medication or invasive procedures,” says Bretherton. “We believe these results are just the tip of the iceberg.”
The findings are reported in a paper in the journal Ageing.
