Science News

Researchers uncover smoking gun in teenagers' brains

Reseachers at Yale Medical School in the US have discovered that smoking during adolescence affects the development of the brain. In particular the regions of the
nervous system that control how we pay attention to sounds and visual stimuli are altered, making the smoker more prone to being distracted. Leslie Jacobsen and her colleagues brain scanned almost 67 teenage volunteers, half of whom smoked, half of whom didn't. Roughly half of the volunteers also had mothers who smoked during their pregnancy. The scans revealed that both pre-natal and teenage exposure to tobacco smoke were associated with changes in the thalamocortical and corticofugal nerve
pathways, which run in a region of the brain called the internal capsule and are concerned with how we pay attention to sounds and other stimuli. The findings agree with a study carried out prevously by Jacobsen and her team in which they showed a link between smoking and a reduced ability to focus on a piece auditory or visual information without being distracted by other things going on at the same time. The researchers suspect that nicotine is probably to blame for the effect because experiments carried out previously on animals have shown that it can affecting the development of nerve connections that control how information flows into the brain. The next step, says Jacobsen, is to brain scan teenagers who have quit smoking.
This will reveal whether the differences she's picked up are reversible or not.

6th Jan 2008