Teen smokers whose mothers smoked during pregnancy have a harder time paying attention and focusing than young people who were not exposed to smoke in the womb, a new study shows.
The researchers also found gender differences in the effect of nicotine exposure, with exposed girls showing both visual and auditory attention deficits, while the boys only had difficulties in listening.
Nicotine is known to bind to receptors involved brain development and studies have identified both intellectual and auditory problems in smokers’ offspring. Both the prenatal period and adolescence are critical times in brain development and smoking has been linked to memory and attention problems in teens.
To better understand the effects of nicotine exposure on attention, Dr. Leslie K. Jacobsen of the Yale University School of Medicine in New Haven and colleagues had 181 teens perform a series of tests to evaluate how well they grasped visual and auditory cues. Sixty-three of the teens had brain scans while they took the tests.
Among the 92 who had been exposed to cigarette smoking in the womb, 67 were themselves daily smokers. Forty-four of the children of non-smoking mothers were current smokers, while 45 didn’t smoke.
Smokers who had also been exposed to nicotine in the womb performed worst, while non-smokers who weren’t exposed in the womb performed best. Study participants who either currently smoked or whose mothers had smoked fell in between.
This pattern was seen for both auditory and visual attention tasks for girls, but only appeared on tests of auditory attention function in boys.
Certain brain regions worked harder during the tests among the nicotine-exposed teens, suggesting that the exposure had lessened the efficiency of brain circuitry involved in processing during the tasks, the researchers note.
The findings suggest that males’ auditory development may be particularly vulnerable to the effects of nicotine exposure, while females are vulnerable in terms of both visual and auditory development, they write.
“The present findings underscore the importance of developing smoking prevention programs that target women of childbearing age and of developing effective programs for tobacco dependence that do not involve nicotine replacement,” the researchers conclude.
They point out that up to 16 percent of female smokers who become pregnant are unable to quit.