A new research has found that stimulating nerves in your ear
could improve the health of your heart. Researchers used a standard TENS machine to apply
electrical pulses to the tragus, the small raised flap at the front of the ear
immediately in front of the ear canal.
They found that the stimulation changed
the influence of the nervous system on the heart by reducing the nervous
signals that can drive failing hearts too hard.
"It is early days - so far we have been testing this on
healthy subjects - but we think it does have potential to improve the health of
the heart and might even become part of the treatment for heart failure,"
said Professor Jim Deuchars of the University
Researchers attached electrodes to the ears of 34 healthy
people and switched on the TENS 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
Lead researcher Dr Jennifer Clancy, said that increased
variability in subjects' heartbeats was the first positive effect.
"A healthy heart does not beat like a metronome
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. We found that when you stimulate this nerve you get about a
20 per cent increase in heart rate variability," Clancy said.
The second positive effect was in suppressing the
sympathetic nervous system, which drives heart activity using adrenaline.
Researchers measured the nerve activity directly and found that it reduced by
about 50 per cent when they stimulated the ear.
"This is significant because if you have heart disease or
heart failure, you tend to have increased sympathetic activity.
This drives your heart to work hard, constricts your
arteries and causes damage. A lot of treatments for heart failure try to stop
that sympathetic activity - beta -blockers, for instance, block the action of
the hormones that implement these signals.
Using the TENS, we saw a reduction of the nervous activity
itself," Clancy added. The study team 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.
A TENS machine is asmall, battery-operated
device that has leads connected to electrodes.
You attach the electrodes to your skin using
self-adhesive pads. When the machine is switched on, small electrical impulses
are delivered to the affected area of your body, which you feel as a
The electrical impulses can block or reduce the pain
signals going to the spinal cord and brain, which can help reduce or relieve
pain or muscle spasm. The electric currents can also stimulate the
production of endorphins, which are the body's natural painkillers.
TENS may be able to help reduce pain and muscle spasms
caused by a wide range of conditions including arthritis, back pain, sports
injuries, period pain, knee pain and neck pain. It's also sometimes used as a
method of pain relief during labour.
A metronome is any device that produces regular, metrical
ticks (beats, clicks) — settable in beats per minutes. These ticks represent
fixed, regular aural pulses; some metronomes also include synchronized visual
motion (e.g. pendulum-swing).