A team of researchers from Dartmouth College found that smokers itch for a cigarette when they watch someone light up in a film as the action is embedded in their minds.
According to them, brain areas known to interpret and plan hand movements lit up as the smokers saw the familiar action.
However, this response wasn`t recorded in non-smokers, they said, adding that the findings could provide additional insight for people trying to overcome nicotine addiction.
"Our findings support prior studies that show smokers who exit a movie that had images of smoking are more likely to crave a cigarette, compared with ones who watched a movie without them," study co-author Dylan Wagner was quoted as saying by Daily Mail.
However, he said that more work is needed to show "whether brain activity in response to movie smoking predicts relapse for a smoker trying to quit".
For their study, the researchers recruited 17 smokers and as many as non-smokers who were asked to watch the movie "Matchstick Men". The volunteers were unaware that their reactions to smoking were being analysed through an MRI scan of their brains.
The researchers chose the movie because it prominently features smoking scenes but otherwise lacks alcohol use, violence, and sexual content.
It was found that when the volunteers viewed smoking scenes, smokers showed greater brain activity in a part of the parietal lobe called the intraparietal sulcus, as well as other areas involved in the perception and coordination of actions.
In the smokers` brains specifically, the activity corresponded to the hand they use to smoke.
"Smokers trying to quit are frequently advised to avoid other smokers and remove smoking paraphernalia from their homes, but they might not think to avoid a movie with smoking content," Wagner said.
Dr Scott Huettel of Duke University, an expert in the neuroscience of decision-making who was unaffiliated with the study, said scientists have long known that visual cues often induce drug cravings.
"This finding builds upon the growing body of evidence that addiction may be reinforced not just by drugs themselves, but by images and other experiences associated with those drugs," he said.
A study in 2003 showed that the movie industry was the biggest factor prompting adolescents to begin smoking. And in 2008, another study claimed that tobacco companies in the 1950s had secretly paid big stars to promote their products.
The new study is published in the Journal of Neuroscience.