Dec 3, 2010 09:10 GMT  ·  By

A new study carried out by German researchers, reported worrying findings about the impact of smoking, on the cerebral cortex.

This is not the first research to report that tobacco smoking is related to large-scale and wide-spread abnormalities in the brain structure, but it is the first one to have focused on the impact of smoking upon cortical thickness.

For the study, the researchers measured cortical thickness in volunteers without medical or psychiatric illnesses, both smokers and never-smokers, and concluded that smokers presented cortical thinning in the left medial orbitofrontal cortex.

Also, the degree of cortical thickness depended on the amount of cigarettes smoked every day, and on the magnitude of lifetime exposure to tobacco smoke, otherwise said, heavy smokers had a thinner cortical tissue.

The cerebral cortex is the extensive outer layer of gray matter of the cerebral hemispheres, widely responsible for higher brain functions like language, information processing, sensation, voluntary muscle movement, thought, reasoning, and memory.

A reduction of the cortical thickness is associated with normal aging, low intelligence and impaired cognition.

The orbitofrontal cortex has been linked to drug addiction, and this new research suggests that smoking-related cortical thinning can contribute to the risk for addictions, including smoking.

Dr. Simone Kühn, co-author of the study, said that “since the brain region in which we found the smoking-associated thinning has been related to impulse control, reward processing and decision making, this might explain how nicotine addiction comes about.

“In a follow-up study, we plan to explore the rehabilitative effects of quitting smoking on the brain.”

John Krystal, MD, Editor of Biological Psychiatry and Professor and Chair of Psychiatry at Yale University, added that “the current findings suggest that smoking may have a cumulative effect on the brain.

“This concerning finding highlights the importance of targeting young smokers for anti-smoking interventions.”

The paper presenting the research is entitled “Reduced Thickness of Medial Orbitofrontal Cortex in Smokers” by Simone Kühn, Florian Schubert, and Jürgen Gallinat.

This study is yet another one adding to the very large list of reasons for which smokers should consider quitting, and it was published in the current issue of Biological Psychiatry.