A new way to stimulate the ear might have a lasting impact on health
Scientists have discovered that two weeks of daily therapy that stimulates the inner ear with an electric current may re-balance the autonomic nervous system for people over 55 years old, according to research a team from the University of Leeds published this week in the scientific journal Aging.
The autonomic nervous system is vital: It controls many of the body’s functions we never consciously think about, like digestion, breathing, heart rate, and blood pressure.
This therapy, called transcutaneous vagus nerve stimulation (tVNS), sends a small, painless electrical current to the ear. This delivers signals along the the vagus nerve, which stretches from the brainstem to internal organs. Patients showed improvement in their mood and sleep, as well as other physiological markers.
The research demonstrates how nerve stimulation can recalibrate the body’s nervous system to ward off diseases common to older people, like high blood pressure, heart disease and atrial fibrillation.
The autonomic nervous system has two sectors — the sympathetic and the parasympathetic — which work together to keep the body in a healthy balance. However, as we age, the body’s balance changes and the sympathetic system dominates, making us more susceptible to breakdown or disease.
Stimulating the vagus nerve recharges the parasympathetic system and bringing it back into balance with the sympathetic.
“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. We believe these results are just the tip of the iceberg,” lead author Dr. Beatrice Bretherton, from the School of Biomedical Sciences at the University of Leeds, said in a statement.
Previous studies required electrodes to be surgically implanted in order to stimulate the vagus nerve. This new therapy instead targets one branch of the nerve that in the outer part of the ear and is therefore non-invasive.
The study was conducted on 29 volunteers who were all over 55 years old, the age group most likely to have an imbalance in their autonomic nervous systems. Researchers gave each one tVNS therapy for 15 minutes per day for two weeks. Results showed an increase in parasympathetic activity and a decrease in sympathetic activity, which shows a balancing of the two sectors.
“We are excited to investigate further into the effects and potential long-term benefits of daily ear stimulation, as we have seen a great response to the treatment so far,” Dr. Bretherton added.