Want a healthy heart? Tickle your ears
A new study has found that tickling in ears stimulates the nerves which could perk up the health of your heart.
A team at the University of Leeds used a standard TENS machine like those designed to relieve labour pains to apply electrical pulses to the tragus, the small raised flap at the front of the ear immediately in front of the ear canal.
The stimulation changed the influence of the nervous system on the heart by reducing the nervous signals that can drive failing hearts too hard.
The researchers applied electrodes to the ears of 34 healthy people and switched on the TENS (Transcutaneous electrical nerve stimulation) machines for 15-minute sessions. They monitored the variability of subjects' heartbeats and the activity of the part of the nervous system that drives the heart. Monitoring continued for 15 minutes after the TENS machine was switched off.
Lead researcher Dr Jennifer Clancy said that the first positive effect observed was the increased variability in subjects' heartbeats. A healthy heart does not beat like a metronome. It is continually interacting with its environment, getting a little bit faster or a bit slower depending on the demands on it. An unhealthy heart is more like a machine constantly banging out the same beat. They found that when this nerve was stimulated, there was around 20 percent increase in heart rate variability.
The second positive effect was in suppressing the sympathetic nervous system, which drives heart activity using adrenaline. They measured the nerve activity directly and found it reduced by about 50 percent when the ear was stimulated.
The researchers found significant residual effects, with neither heart rate variability or sympathetic nerve activity returning to the baseline 15 minutes after the TENS machine had been switched off.
The technique works by stimulating a major nerve called the vagus, which has an important role in regulating vital organs such as the heart. There was a sensory branch of the vagus in the outer ear and, by sending electrical current down the nerves and into the brain, researchers were able to influence outflows from the brain that regulate the heart.
(Posted on 20-08-2014)