A new study has found that people who were exposed to tobacco smoke when in the womb struggled to process tasks that measured inhibition control.

Functional magnetic resonance imaging was performed at age 25 years on young adults who had been followed since birth to examine the effect of prenatal tobacco smoke exposure on neural activity implicated in externalizing disorders, such as ADHD, with measures of inhibitory control. Lifetime ADHD symptoms were measured over a period of 13 years (from 2 to 15 years of age). The study included 178 mothers (140 of whom were nonsmokers) and 175 offspring for whom ADHD symptoms were measured throughout childhood.
Individuals prenatally exposed to tobacco smoke exhibited less activity in regions of the brain in response to a task that measured inhibitory control vs. neutral stimuli. The group prenatally exposed to tobacco smoke also exhibited more lifetime ADHD symptoms.
"Therefore, our findings strengthen the importance of smoking cessation programs for pregnant women, and women planning to become pregnant, to minimize prenatal exposure to tobacco smoke by the offspring."
Source-Eurekalert