Brain scans can predict how likely someone is to quit smoking, a new study suggests. And these images do a better job at foretelling quitting success than the smokers themselves.

The study involved 28 heavy smokers who were actively attempting to quit the habit. The researchers showed the smokers a series of television ads designed to help people quit smoking , and scanned their brains with functional magnetic resonance imaging.

The results showed an association between activity in a certain region of the brain and successfully quitting smoking, even when test subjects erroneously predict the likelihood of their success.

"These results bring us one step closer to the ability to use functional magnetic resonance imaging to select the messages that are most likely to affect behavior change, both at the individual and population levels," said study researcher Emily Falk, director of the University of Michigan's Communication Neuroscience Laboratory. "It seems that our brain activity may provide information that introspection does not."

The study participants completed a questionnaire on their smoking history, degree of nicotine dependence , cravings and intentions to quit. Each was also tested for exhaled carbon monoxide (CO), a measure of recent smoking.

After seeing watching the TV ads while in the brain scanner, the participants rated how they affected their intention to quit, whether it increased their confidence about quitting and how much they related to the message.

A month after the scan, researchers contacted participants to ask how they were doing and to measure their CO levels to verify how much they were smoking .

At that point, the participants reported smoking an average of five cigarettes a day, compared with an average of 21 cigarettes a day at the start of the study, and CO levels were consistent with these self-reports, the study showed.

The researchers compared the smokers' behavior change from the start to the end of the study with activity in a particular brain region called the medial prefrontal cortex. The team's previous research had suggested changes in activity in this region may predict behavior changes.

The team found that neural activity in this region was significantly linked to reductions in smoking behavior over the month following the scan, predicting how successful people would be in reducing their smoking.

"It is possible that the brain activity we are observing predicts behavior change that is not predicted by people's self-reports, because it is tapping into something that people aren't consciously aware of when they initially see the ads," Falk said.

The study will be published in an upcoming issue of the journal Health Psychology.

Pass it on: Brain scans performed while people watch a smoking-cessation message can predict how likely they are to quit smoking.

Follow MyHealthNewsDaily on Twitter @MyHealth_MHND.