Investigation reveals the brain circuitry that causes people trying to quit smoking to experience anxiety

Apr 22, 2015 11:45 GMT  ·  By

A paper published in yesterday's issue of the journal Nature Communications details the mechanisms that are at play when people try to quit smoking and why it is that nicotine withdrawal correlates with anxiety and other troublesome symptoms.

The study, authored by scientists with the University of Massachussets and colleagues at the Scripps Research Institute, could help make it easier for smokers to kick the habit by paving the way for the development of drugs that tackle the symptoms associated with nicotine withdrawal.

Why quitting smoking often causes anxiety

In their report in the journal Nature Communications, the specialists behind this research project explain that, according to evidence at hand, quitting smoking activates a specific area of a brain region known as the interpeduncular nucleus.

This brain area becomes active because, following nicotine withdrawal, it is bombarded by compounds that serve as neurotransmitters. These compounds come from other brain regions, of which one has previously been associated with substance abuse.

It is when bombarded by the neurotransmitters produced in response to nicotine withdrawal that this specific area of the interpeduncular nucleus turns hyperactive and people begin to experience feelings of anxiety, the researchers explain.

Most of the time, the anxiety proves too much to handle and people find themselves lighting yet another cigarette. As explained by scientist Andrew Tapper, “Increased anxiety is a prominent nicotine withdrawal symptom that contributes to relapse in smokers attempting to quit.”

Interestingly, the researchers say that the nausea, the insomnia and the headaches that come with quitting smoking originate in a different area of the brain's interpeduncular nucleus than the anxiety. This just goes to show how complex the brain is.

Helping people quit smoking once and for all

The University of Massachussets scientists and their colleagues imagine using this information to develop a new generation of drugs that target the brain's interpeduncular nucleus and keep it from becoming active during nicotine withdrawal.

Should these drugs prove to do away with the anxiety, the nausea, the insomnia and the headaches caused by quitting smoking, odds are more people would kick this habit once and for all.

Several such compounds have already been tested on mice and proven effective in terms of silencing the interpeduncular nucleus and reducing feelings of anxiety. Whether the compounds could also work on people remains to be seen.