Brains of some smokers hardwired to quit
Brains of smokers who successfully quit the habit may be hard-wired to make them strong-willed, research has shown.
Certain brain regions, including one involved in addiction, are more connected in people who manage to stop smoking compared with those who fail, scientists say.
The evidence suggests some people are better at overriding craving signals from the insula brain region urging them to light up another cigarette.
Lead scientist Dr Merideth Addicott, from Duke University in North Carolina, US, said: "Simply put, the insula is sending messages to other parts of the brain that then make the decision to pick up a cigarette or not."
The researchers analysed the results of magnetic resonance imaging (MRI) brain scans of 85 smokers conducted one month before they tried to quit.
All the participants stopped smoking initially, but over a period of 10 weeks 41 relapsed. The brain scans of the 44 who succeeded showed they all had one thing in common - greater co-ordinated activity between the insula and somatosensory cortex, a part of the brain central to our sense of touch and motor control.
The insula, a large region within the brain's cerebral cortex, is known to be active when smokers crave cigarettes. Other studies have shown that smokers who suffer damage to the insula appear to lose interest in smoking.
Dr Joseph McClernon, another member of the Duke team, said: "There's a general agreement in the field that the insula is a key structure with respect to smoking and that we need to develop cessation interventions that specifically modulate insula function. But in what ways do we modulate it, and in whom? Our data provides some evidence on both of those fronts, and suggests that targeting connectivity between insula and somatosensory cortex could be a good strategy."