Cant quit smoking? Blame faulty wiring in the brain

London: Can`t quit smoking? Blame the faulty wiring in your brain, say scientists.

A team at the Scripps Research Institute have discovered a brain pathway which they say, if not functioning correctly, can lead to an uncontrollable desire to smoke, the `Daily Mail` reported.

The fault lies in a receptor protein that is normally activated by the nicotine in cigarettes and dampens the desire for yet more of the drug, say the scientists.

In their research, the scientists found that when rats were genetically changed to block the protein they consumed far more nicotine than control animals.

Prof Paul Kenny, who led the team, was quoted as saying, "These findings point to a promising target for the development of potential anti-smoking therapies.`

The study, published in the `Nature` journal, focused on the chemical alpha-5 in a brain pathway known as the habenulo-interpeduncular tract.

Co-researcher Dr Christie Fowler said: "It was unexpected that the habenula, and brain structures into which it projects, play such a profound role in controlling the desire to consume nicotine.

"The habenula appears to be activated by nicotine when consumption of the drug has reached an adverse level. But if the pathway isn`t functioning properly, you simply take more."

She said the data could explain why some people are far more vulnerable to the addictive properties of nicotine and more likely to develop smoking associated diseases such as lung cancer.