brainlessParents now have another reason to worry about their children smoking.

Nicotine might cause the teenage brain to develop abnormally, resulting in changes to the structure of white matter — the neural tissue through which signals are relayed. Teenagers who smoke, or whose mothers smoked during pregnancy, are also more likely to suffer from auditory attention deficits, meaning they find it harder to concentrate on what is being said when other things are happening at the same time.

Leslie Jacobsen of Yale University School of Medicine and colleagues used diffusion tensor imaging, which measures how water diffuses through brain tissue, to study the brains of 33 teenagers whose mothers had smoked during pregnancy. Twenty-five of the teens were daily smokers. The team also studied 34 teens whose mothers had not smoked, of whom 14 were daily smokers.

Both prenatal and adolescent exposure to tobacco smoke were associated with changes in white matter in brain pathways that relay signals to the ear.

The changes were greatest in teenagers who smoked, suggesting the brain is particularly vulnerable to the effects of nicotine during adolescence, when many neural pathways are maturing (Journal of Neuroscience).
Continue Reading »