"We found that if this specific area of the brain is damaged, addiction to smoking gets wiped out," said Antoine Bechara, PhD, UI adjunct associate professor of neurology and associate professor of psychology and neuroscience at USC. "This is important because now we have identified a target for disrupting addiction, which gives us hope for developing new strategies to break the cycle of addiction."

The findings may point the way to pharmacological treatments for addiction that target the insula and also suggest that functional imaging of the insula may be a good way to monitor the success of addiction treatments. The findings are published in the Jan. 26 issue of the journal Science and in Science Express online Jan. 25.

Nasir Naqvi, an MD/PhD student in the UI Medical Scientist Training Program, is first author of the study.

The study involved 69 patients with brain damage, all of whom had smoked more than five cigarettes per day for more than two years prior to their injury. Patients with insula damage were much more likely to have quit smoking easily and without relapse than patients with damage in other brain areas. In fact, in most cases, damage to the insula caused patients to completely lose the urge to smoke.

Comparing only patients who quit smoking after brain injury, the study found that 12 of 13 patients with insula damage lost their addiction compared to four of 19 patients with non-insula damage.

Bechara believes the insula likely plays a role in maintaining addiction of any kind. He also speculates that the finding may have implications for obesity treatments.

"It is possible that disrupting insula function might disrupt learned habits like overeating," he said.

The insula helps translate bodily sensations into conscious feelings and recent functional neuroimaging studies also suggest that the insula is important for conscious urges and cravings. The results of Bechara and Naqvi's study suggest that conscious urges may play an important role in maintaining addiction.

In addition to Bechara and Naqvi, the research team included David Rudrauf, PhD, UI postdoctoral research scholar in neurology, and Hanna Damasio, MD, a distinguished adjunct professor at the UI and the Dana Dornsife Professor of Neuroscience, director of the Dana and David Dornsife Cognitive Neuroscience Imaging Center and professor of psychology, neuroscience and neurology at the University of Southern California.

The study was funded by the National Institute on Drug Abuse and the National Institute of Neurological Disorders and Stroke.

For more information:

Antoine Bechara, PhD

National Institute on Drug Abuse

National Institute of Neurological Disorders and Stroke