Children who were exposed to cigarette smoke prenatally may be at increased risk of addiction, a new study suggests. The smoke may interfere with the brain’s reward processing system, Time.com reports.
German researchers studied 177 teenagers who had been exposed to cigarettes prenatally, and 177 teens whose mothers did not smoke during pregnancy. The researchers studied how participants reacted when they were presented with a reward, which simulated the need to satisfy an addiction, the article notes.
The teens were placed in a functional MRI machine that recorded their brain activity as they performed computer-based tasks. They were instructed to press a button to indicate on which side of the screen a figure appeared. They were told they would receive a reward if they pressed the correct button fast enough. The researchers varied the time the figures appeared on the screen, so they could determine how quickly participants reacted, focusing on an area of the brain thought to be depressed by nicotine.
They found less activity in this brain area in teens whose mothers smoked during pregnancy, compared with the teens whose mothers did not smoke while pregnant. Teens exposed to prenatal smoke took longer to respond to the figures that appeared on the screen.
The researchers wrote in JAMA Psychiatry that the weaker response in this area of the brain, called the ventral striatum, to regard anticipation in teens exposed prenatally to cigarette smoke “may represent a risk factor for substance use and development of addiction later in life.” They explained the reduced activity of brain chemicals that signal satisfaction may lead people to continue to seek a high, and become addicted to particular substances or behaviors.