Scientists at the University of Cambridge have discovered how the brain becomes addicted to nicotine, which is the single biggest cause of cancer in the UK and responsible for over a quarter of all cancer deaths. The study involved over 800 people aged 14, 19, and 24 who were scanned to understand the impact of smoking. The researchers found that smokers were more likely to have a smaller region in the frontal lobe called the left ventromedial prefrontal cortex, which is linked to rule breaking. However, the right-hand side of the same brain region, involved in controlling willpower and triggering pleasure, shrinks in smokers. This reduction in brain grey matter volume is associated with sensation-seeking and pleasurable experiences, which reinforce and maintain future cigarette smoking, eventually leading to addiction.
The study published in Nature Communications found that nicotine was associated with significant changes after people started smoking. The researchers believe that the nicotine effect found with smoking cigarettes may also apply to e-cigarettes, as both e-cigarettes and regular cigarettes contain nicotine, which is highly addictive. The scientists believe they have discovered a "neurological mechanism" which underpins how people start smoking and what makes it so hard to quit.
The team suggests that therapies such as psychotropic drugs could stop the brain shrinking or keep the frontal lobe working normally. Brain-zapping technology could also be used as a potential treatment for addiction.
