Around 3 billion people worldwide currently drink or smoke - new research could help in both the prevention and treatment of alcohol and nicotine substance abuse.

Researchers have found that low functional connectivity of the lateral orbitofrontal cortex that is associated with the tendency to smoke is associated with increased impulsiveness - which may contribute to the tendency to smoke. The high connectivity of the reward-related medial orbitofrontal cortex in drinkers may increase the tendency to be attracted to the reward of alcohol consumption.

In 2000 participants they found that smokers had low functional connectivity in general, and especially in the lateral orbitofrontal cortex, a region of the brain associated with impulsive behavior. This suggests that people who smoke may do so to increase their overall brain connectivity with the stimulating effect of nicotine; and that being impulsive may be a factor leading to smoking.

Drinkers of alcohol had high overall brain connectivity, especially in the medial orbitofrontal cortex, a region implicated in reward. It is suggested that the high connectivity of this reward-related brain region may be a factor in attracting some individuals to alcohol.

Importantly the extent of these functional connectivity changes in the brains of drinkers and smokers correlated with the amount of alcohol and nicotine being consumed. Critically they were even detectable in individuals smoking only a few cigarettes or drinking one unit of alcohol every day.

Another key discovery is that it was possible to relate the connectivity at age 14 to who would smoke or drink at age 19. This opens up the issue of causality in addiction.

"These are key discoveries that advance our understanding of the neurological bases of smoking and drinking and also provide new evidence on the different neurological mechanisms that are related to these two types of human addictive behavior, smoking and drinking, and these advances have implications for prevention and treatment of these two substance use."

https://warwick.ac.uk/newsandevents/pressreleases/discovered_different_brain

https://elifesciences.org/articles/40765

http://sciencemission.com/site/index.php?page=news&type=view&id=publications%2Fdecreased-brain&filter=22