"What we believe this means is that smokers who just quit have a more difficult time shifting gears from inward thoughts about how they feel to an outward focus on the tasks at hand," Lerman added. It is very important for people who are trying to quit, to be able to maintain activity within the control network-to be able to shift from thinking about yourself and your inner state to focus on your more immediate goals and plan, suggested Elliot Stein from NIDA.

For the study, researchers conducted brain scans on 37 healthy smokers (those who smoke more than 10 cigarettes a day) aged 19 to 61 using functional magnetic resonance imaging (fMRI) in two different sessions. Imaging showed a significantly weaker connectivity between the salience network and default mode network during abstinence. The weakened connectivity during abstinence was linked with increases in smoking urges, negative mood and withdrawal symptoms-suggesting that this weaker inter-network connectivity may make it more difficult for people to quit. The next step is to identify in advance those smokers who would have more difficultly quitting and target more intensive treatments, based on brain activity and network connectivity, said the study, published in the journal JAMA Psychiatry.

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