Smoking may change the brain structure in teenagers, a new study suggests.
Past studies have shown the link between smoking and a change in structure of various brain regions.
"While the results do not prove causation, they suggest that there are effects of cigarette exposure on brain structure in young smokers, with a relatively short smoking history," said senior author Edythe D. London, according to a Reuters report.
Young people ages 18 to 25 have the highest smoking rates in the United States at 30 percent, London said.
London and her UCLA team asked 42 people ages 16 to 21 about their smoking habits and mapped their brains using magnetic resonance imaging (MRI). Eighteen of these participants were smokers, having started around age 15 and smoking six to seven cigarettes a day.
MRIs of the smokers and nonsmokers showed a slight change in a region of the cerebral cortex, which is involved in decision-making. This area, called the insula, was thinner in smokers, especially those that smoked more cigarettes - perhaps not all too surprising since the insula is thought to play a central role in tobacco dependence.
"It is possible that changes in the brain from prolonged exposure help maintain dependence," London said.
Dr. Nasir H. Naqvi, a substance abuse researcher at Columbia University in New York City who was not involved in the study, says the insula acts as a "brake pedal," and gives people less control over their cravings.
"The key question is whether these changes are reversible with smoking cessation, or whether they persist," Naqvi added. "What we do know is that once you are addicted to smoking, you will always have a high likelihood of relapse, even if you are abstinent for many years."
