- Published
Lola Baird has just asked her boyfriend to pull over.
asserted
Baird → publish → boyfriend
Forty minutes into a journey and she's feeling "overwhelmed" by nausea - and can't stop herself throwing up on the ground next to his car.
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herself → feel → car
Lola, 24, from north London, had never experienced motion sickness until her boyfriend bought an electric vehicle (EV) two years ago.
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boyfriend → experience → vehicle
Ever since, she's been feeling "very nauseous" when he takes her on long car journeys.
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he → feel → journeys
It's become so severe she's even asked him to change his car.
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she → become → car
Other people told BBC News that they or their children notice feeling more car sick when sitting as a passenger in an electric vehicle.
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they → tell → vehicle
But at the same time, many EV drivers say it's not been a concern.
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it → say → time
So what could explain these reports of motion sickness?
uncertain
what → explain → sickness
Dr Irene Di Giulio, senior lecturer in anatomy and biomechanics at King's College London whose research includes motion sickness, says research so far suggests some people experience more severe motion sickness in electric vehicles than in non-electric vehicles.
uncertain
people → include → vehicles
It's something Dr Nicholas Hac, a neurologist at Northwestern Medicine in Chicago who specialises in dizziness and vertigo, has also heard from some of his patients.
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who → specialise → patients
"They just notice that they're much more likely or prone to be motion sick" in electric vehicles, he says.
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he → notice → vehicles
"I've heard about it many, many, many times," he adds, saying about two patients a month specifically reference feeling motion sick in electric vehicles.
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patients → hear → vehicles
But research into any possible link is still in its early stages, and some academics say there isn't sufficient evidence to say anything definitive.
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academics → say → anything
Dr Bill Yates, who has researched motion sickness at the University of Pittsburgh, says the body of research is "pretty sketchy at this point".
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body → research → point
"There's some anecdotal information, but not a lot of really serious, extensive studies done yet," he says.
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he → be → studies
'Wonderful to drive... but my daughter gets unwell'
When Mark Quigg was looking at options for a new car last year, an electric vehicle seemed like the best choice because of the lower running costs.
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vehicle → drive → costs
Mark, 45, from Lincolnshire, says his shiny new electric vehicle has been "wonderful" to drive - but he quickly noticed that his nine-year-old daughter's motion sickness got much worse in it.
She used to get motion sick only on their 600-mile drives to France during the school holidays, but now he says even the 30-minute drive to the nearest city makes his daughter feel unwell.
On one recent journey, he says his daughter even threw up, which had never happened before.
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which → say → journey
Motion sickness doesn't affect all EV passengers - many owners got in touch with BBC News to say they and their relatives don't get sick in electric vehicles.
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they → affect → vehicles
Others said they felt less sick in EVs compared with traditional combustion engine cars.
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they → say → cars
Vicky Edmonds, the CEO of EVA England, an association for electric vehicle drivers, says motion sickness isn't a concern among her members.
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sickness → say → members
"This has never come up as an issue," she says.
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she → come → issue
But Chinese electric vehicle maker XPeng, which has showrooms across the UK, has previously publicly addressed the issue, external, telling people who've noticed a link between electric vehicles and travel sickness that "it's a fair question, and it's not your imagination".
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it → have → vehicles
It's caused by "side effects of how electric cars are engineered," it adds.
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it → cause → effects
What could cause it?
uncertain
What → cause → it
Motion sickness is caused by "a mismatch in sensory cues," Hac says.
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Hac → cause → cues
Our bodies rely on three main sensory inputs to show that we're moving, which come from what we see, what our inner ear's balance system perceives, and what fibres in our body sense, he says.
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he → rely → body
When one of these is in conflict with the others - like if you're looking at your phone so you don't see visual signs of movement out of the window - that can cause motion sickness.
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that → look → sickness
Research suggests several reasons why it may be more severe in electric vehicles.
uncertain
it → suggest → vehicles
Humans have adapted to associate sound with movement in vehicles, experts explain.
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experts → adapt → vehicles
Because electric vehicles don't have the auditory cues and vibrations from the engine that we're used to, which indicate when the car is accelerating, this could trigger motion sickness, Di Giulio says.
uncertain
Giulio → have → sickness
Another reason is regenerative braking, the process whereby when drivers release the accelerator, the electric car starts to slow down and uses the energy to feed the battery.
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car → release → battery
However, it is a process that needs to be done smoothly with the accelerator being released gently, or it can lead to harsh deceleration.
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it → need → deceleration
"It forces the person to perhaps feel like they're rocking back and forth for that brief moment when the speed of the car suddenly changes," says Hac.
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Hac → force → car
This is something Carolyn Le, 24, from California, has noticed.
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Le → notice → California
She gets "horrendous" motion sickness when her friend drives her in his electric vehicle in busy cities, she says.
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she → get → cities
The regenerative braking means it "constantly feels like the car is stopping all the time".
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car → mean → ?
Electric vehicles can also accelerate and decelerate much more quickly than conventional combustion cars, which Di Giulio says can cause motion sickness.
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Giulio → accelerate → sickness
Edmonds, of EVA England, says developments in electric vehicle design have made them better at moderating the acceleration so they don't gain speed as rapidly.
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they → say → speed
She adds that the association thinks motion sickness in an electric vehicle is caused by "other factors" like the motorist's driving style rather than the vehicle itself.
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sickness → add → style
Some people are also just more prone to motion sickness, and genetics have the biggest influence on this, Hac says.
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Hac → have → this
…and 16 more, not listed.
The Aporia
