Children born to mothers who smoke are more irritable, according to new research at the University of Nebraska-Lincoln.
The research, funded by a five-year $2.3 million grant from the National Institute on Drug Abuse, found that babies whose mothers smoked during pregnancy tended to have more trouble focusing than babies from mothers who didn't smoke.
"At this stage in development, there were significant differences," said Kimberly Espy, associate vice chancellor of research.
Espy began her research after doing similar studies on the effects of a mother's cocaine use on her baby. Espy became interested in the effects of smoking because it's more frequent than cocaine use.
"I wanted to look at a substance that's legal and used consistently," Espy said.
The research was preformed by studying pregnant women from diverse backgrounds, half who were smokers and half who were not.
After the babies were born, they went through a number of behavioral tests to measure their temperament and reactions to certain stimuli. The tests included talking to the babies, observing how they played with toys and changing their feeding schedule.
"They show the relation of how kids pay attention and how they regulate emotion," Espy said.
Preliminary results from these tests showed that babies from mothers who smoked had slower reaction times and tended to have trouble paying attention to one thing, which could lead to increased irritability.
"Babies who have an easier time controlling their attention are not as easily annoyed by every little thing in their environment," said Sandra Wiebe, a research assistant professor.
Wiebe said the nicotine in cigarettes seems to be the main cause for the behavior changes. Nicotine in the mother's system activates receptors in the baby's brain that normally remain closed. The baby's brain has to adjust to these new receptors.
"The receptors guide how the brain develops," Wiebe said.
The study also found that the the number of times a mother smoked and how long into the pregnancy she smoked had an effect on the severity of her baby's behavioral differences.
"The amount of difference we saw was directly proportional to the amount the mother smoked," Espy said.
Espy said she hopes to get additional funding for the research to continue studying the babies for a longer period of time and to see if the mothers' smoking habits have long-term impacts on their babies' personalities.
"There are some early indicators of long-range effects," Espy said.
Espy said that finding these early causes of children's behavior will help treat behavioral problems that might arise later in life.
"It gives a leg up to understanding certain behaviors," Espy said.
adamziegler@dailynebraskan.com
