Quitting Smoking Blunts the Reward System in the Brain

Quitting smoking blunts

Researchers find that quitting smoking blunts the reward system in the brain, making it harder to quit.

Cigarette smoking causes more than 480,000 deaths each year in the US. That is one of every five deaths in the US annually. Even though people know that smoking is dangerous about 20% of the US population continues to smoke cigarettes. About half of smokers try to quit each year but only about 10% are able to stay smoke free. The withdrawal is so powerful people usually relapse within 48h.

Quitting Smoking Blunts the Brain’s Reward System

In the study researchers investigated how nicotine addiction and nicotine withdrawal affect the brain’s response to reward. The brain responds to reward such as sex, food and exercise by releasing signaling molecules that provides positive feelings. Being deprived from smoking blunts this reward system which can lead to depression in people.

In the study the researchers included people who smoked at will  and compared those with people with a 24h withdrawal from nicotine with about half having a history of depression. The study also included rats 24h after nicotine withdrawal. The results of the study showed that both people and rats had a weaker reward response after being deprived of nicotine for 24 hours. The weaker response to reward were greater in the people who had a history of depression.

That quitting smoking blunts the reward response might play a role in the frequent relapses of people who try to kick the habit. The feeling that nothing helps to ease the discomfort they feel for the first two days after quitting is probably a huge factor in starting with the bad habit again. This research shows that rats and humans responds similarly to quitting nicotine can possibly be helpful in future addiction research.

The study further highlights that the drug have similar effect to the reward system as marijuana.

image credit: Ferran Jordà via flickr.com in accordance with CC BY-NC-ND 2.0