Scientists have discovered a brain network that is connected to addiction.

Scientists have discovered a brain network that is connected to addiction.

Researchers said on Monday that they had mapped the brain network connected to addiction by studying long-term smokers who quit abruptly after brain damage.

They hope that the findings will serve as a benchmark for future treatments in the fight against drug and alcohol addiction.

The researchers looked at 129 patients who were daily smokers when they suffered a brain lesion to see where addiction is located in the brain.

According to a new study published in the journal Nature Medicine, while more than half of those who had the lesion continued to smoke as usual, a quarter of those who got the lesion quit smoking without difficulty — even expressing a "absence of craving."

Scientists linked the lesions of people who stopped smoking to a multitude of regions — what they named the "addiction remission network" — rather than one specific region of the brain.

They discovered that a lesion that causes someone to quit smoking would most likely damage the dorsal cingulate, lateral prefrontal cortex, and insula — but not the medial prefrontal cortex.

Previous studies has indicated that insula lesions can help with addiction. However, it fails to account for other areas of the brain discovered in the latest study.

The researchers evaluated 186 lesion patients who completed an alcohol risk assessment to corroborate their findings.

Lesions in the patients' addiction remission network were shown to lower the probability of alcoholism, "suggesting a shared network for addiction across different substances of abuse," according to the study.

"The found network presents a testable target for therapeutic efforts," Juho Joutsa, a neurologist at Finland's University of Turku and the study's lead author, told AFP.

"Some of the network's hubs were found in the cortex," he noted, "which might be targeted even with non-invasive neuromodulation approaches."

Neuromodulation is a technique for treating a variety of illnesses by stimulating nerves.

The transcranial magnetic stimulation (TMS) coil, which was approved by the US Food and Drug Administration last month for obsessive-compulsive disorder, is an example of such a treatment.

It already affects many of the same brain locations as the addiction remission network discovered in Monday's research.

Joutsa expressed the hope that his research might lead to the development of a TMS coil that could be used to treat addiction.

"However, we still need to figure out the optimal strategy to regulate this network," he added, "and perform well designed, randomised, controlled trials to see if targeting the network is clinically useful."