Scientists are working on a motion sickness treatment based on brain stimulation that could one
day become an easy-to-use portable device you pick up from the pharmacy, or even apply directly from
your smartphone.
The researchers say the results show the device offers benefits that are close to those of the best travel sickness
medications available.
Researchers from
Imperial College London in UK state that the treatment – which delivers a mild electrical current to the brain – lasts for around 10 minutes,
works by applying electrodes to the scalp and appears to have no side effects.
A small trial of the device that they report in the journal Neurology shows it has promise
as a new treatment for motion sickness.
“We are confident that within 5 to 10 years people will be able to walk into the chemist and
buy an anti-seasickness device,” says lead author Dr. Qadeer Arshad, a researcher in the Department
of Medicine.
Another author, Michael Gresty, a visiting professor at Imperial and world expert on spatial
orientation and motion sickness, explains the benefit such a device could bring to people constantly
plagued by motion sickness:
“The problem with treatments for motion sickness is that the effective ones are usually tablets that
also make people drowsy. That’s all very well if you are on a short journey or a passenger, but what
about if you work on a cruise ship and need to deal with motion sickness whilst continuing to
work?”
Motion sickness is a common condition that most people have experienced at one time or another –
perhaps on a turbulent ferry crossing, or on a particularly rough rollercoaster ride. But for around 3
in 10 people, it can involve much worse symptoms such as severe nausea, vomiting, dizziness and cold
sweats.
Transcranial direct current stimulation
Nobody knows exactly what triggers motion sickness, but many scientists believe it has something to
do with the brain trying to process conflicting signals from our ears and our eyes when we are
moving.
Previous research has shown that a functioning vestibular system – the part of the inner ear that
senses movement – plays an important role in the development of motion sickness. Dr. Arshad and
colleagues decided to test what happens to symptoms of motion sickness if you dampen the signals from
the vestibular system to the brain.
One way to dampen the movement signals from the inner ear is to apply transcranial direct current
stimulation through the scalp to the brain region responsible for processing them.
Transcranial direct current stimulation (tDCS) is a non-invasive, painless treatment that uses weak,
direct electrical currents to stimulate specific parts of the brain.
There are two types of tDCS – anodal stimulation, which increases brain cell activity, and cathodal
stimulation, which inhibits or reduces it.
For their study, the researchers invited ten men and ten women to wear a cap fitted with electrodes
on their heads through which they underwent tDCS for approximately 10 minutes. They then underwent a well-tested method of simulating motion sickness where they sat in a chair that rotates and tilts at
different speeds.
Participants receiving tDCS had less nausea and recovered more quickly
The trial was a double-blind trial in that neither the participants nor the technicians
administering the treatment knew whether the tDCS being given was the type that dampens the inner ear signals
(cathodal stimulation) or not (anodal stimulation). Participants had been randomly assigned to receive
either one or the other.
The results showed that the volunteers who received the correct treatment were less likely to feel
nauseous and recovered more quickly.
Prof. Gresty says they are very excited about the potential of the device to offer an effective
alternative to current treatments with no apparent side effects. “The benefits that we saw are very close to the effects we see with the best travel sickness
medications available,” he adds.
The team is already in talks with potential industry partners about developing the device further. Other
parties have also expressed interest. One potential military use for the device, for example, would be to treat remote
control drone operators who can get motion sickness from looking at screens that show what the drone
cameras see.
In the future, Dr. Arshad foresees the development of a device similar to a TENS (transcutaneous electrical nerve stimulation) machine that is used to treat back pain, or
perhaps something even more portable:
“We hope it might even integrate with a mobile phone, which would be able to deliver the
small amount of electricity required via the headphone jack. In either case, you would temporarily
attach small electrodes to your scalp before traveling – on a cross-channel ferry, for
example.”
He says the currents involved are very weak and can see no reason to expect any adverse side effects
from short-term use. In the following video, Dr. Arshad describes the device, how the team tested it and how people might use it in the future:
Currently, tDCS is still considered an experimental form of brain stimulation – it is yet to be approved
by the US Food and Drug Administration (FDA).
However, earlier this year, Medical News Today reported that the FDA has approved a
different type of brain stimulation device that reduces Parkinson’s
disease symptoms and essential tremor by sending weak electrical pulses via electrodes implanted
in the brain.
Written by Catharine Paddock PhD
Copyright: Medical News Today
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