British scientists say they have found the best way yet to analyse the effects of smoking on the brain – by taking functional magnetic resonance imaging (fMRI) scans of people while they puff on e-cigarettes.
Studies could help understand why smoking is addictive
In a small pilot study, the researchers used electronic cigarettes, or e-cigarettes, to mimic the behavioural aspects of smoking tobacco cigarettes, and say future studies could help scientists understand why smoking is so addictive.
E-cigarettes use battery-powered cartridges to produce a nicotine-laced vapour to inhale – hence the new term "vaping".
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Their use has rocketed in recent years, but there is fierce debate about the risks and benefits. Some public health experts say they could help millions quit tobacco cigarettes, while others argue they could "normalise" the habit and lure children into smoking.
While that argument rages, tobacco kills some 6 million people a year, and the World Health Organisation estimates that could rise beyond 8 million by 2030.
Matt Wall, an imaging scientist at Imperial College London who led the study using e-cigarettes, said he was not aiming to pass judgment on their rights or wrongs, but to use them to dig deeper into smoking addiction.
Hooked on more than just nicotine
The fact that other forms of nicotine replacement therapy, such as patches or gum, have had only limited success in getting hardened smokers to quit suggests they are hooked on more than just nicotine, he noted.
"There's something unique about the drug (nicotine) and the delivery system- the smoking- combined which makes it really, really addictive," he told Reuters.
And by analysing the brains of people "smoking" or "vaping" e-cigarettes, scientists can study the brain effects of what he called the "the behavioural and sensory repertoire of smoking."
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Until now, it was impossible to monitor these effects with conventional cigarettes due to the difficulty of having people smoke in the confined space of an MRI scanner.
But because e-cigarettes produce water vapour and do not burn, Wall's team could record brain activity with each drag.
Wall said the study was not large enough to draw any firm conclusions yet, although it did show interesting activity in brain areas linked to reward and addiction, and in areas involved in perception of taste and smell.
"E-cigarettes ... provide a very good simulation of traditional smoking (and) we have shown that using e-cigarettes with fMRI is an excellent paradigm for direct evaluation of the effects of smoking on human neurophysiology," he said.
Read: 1 in 4 people with lung cancer never smoked
The plan now is to conduct larger studies using "vapours".
Wall's findings were due to be presented at the Global Addiction Conference in Rio de Janeiro.
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Image: Electronic cigarette next to a cigarette from Shutterstock.