New research suggests teens who smoke cigarettes even for a short period of time experience morphological changes in the brain that can lead to long-term dependancy.
"Although we are not certain whether the findings represent the effects of smoking or a genetic risk factor for nicotine dependence, the results may reflect the initial effects of cigarette smoking on the brain," senior author Edythe London, a professor of psychiatry and of molecular and medical pharmacology at UCLA's Semel Institute for Neuroscience and Human Behavior and David Geffen School of Medicine, said in a news release. "This work may also contribute to the understanding of why smoking during this developmental stage has such a profound impact on lifelong smoking behavior."
The researchers found differences in the the insula of young smokers and non-smokers; the insula is the part of the brain "a part of the brain's cerebral cortex that is involved in monitoring internal states and making decisions," the news release reported. This part of the brain has been know to have a primary role in tobacco dependence.
Researchers looked at 42 participants between the ages go 16 and 22; they took the subjects' smoking histories, tobacco cravings, and insula structure into account. Out of the participants 24 were non-smokers and 18 were smokers. Those who smoke picked up the habit around the age of 15 and smoked less than seven cigarettes per day. The team assessed the cortical thickness of the participants' insula and found it was negatively related to the number of years they had been smoking. The longer someone had smoked the thinner the right side of the insula was.
"Our results suggest that participants with greater smoking exposure had more severe nicotine dependence, more cigarette craving and less insular thickness than those with less exposure," London said. "While this was a small study and needs to be replicated, our findings show an apparent effect of smoking on brain structure in young people, even with a relatively short smoking history. And that is a concern. It suggests that smoking during this critical time period produces neurobiological changes that may cause a dependence on tobacco in adulthood."
