How well parents manage stress and conflict during pregnancy may impact the fetus's brain development and future emotional and behavioral health, according to new research from the Harvard School of Public Health.
In a study published earlier this month, School of Public Health professor Henning Tiemeier and associated researchers found that poor family functioning during pregnancy leads to smaller hippocampus and occipital lobe sizes in childhood. The study contributes to an established body of scholarship on the effect of environmental factors on emotional and behavioral issues.
The researchers tracked a cohort of 2,583 mothers and their children, who were born between 2002 and 2006 in Rotterdam, the Netherlands. Tiemeier said that this is the second biggest cohort of preadolescents involved in a brain imaging study to date.
Tiemeier said he has always been interested in studying what shapes the brain development of children, but that he was particularly intrigued by how the brain is shaped by our environment and behavior.
"Family conflict and family separation are one of the most important determinants of child developmental and child psychiatric problems — that’s [been] known for about 50 years,” Tiemeier said. “So I was interested in, can we see correlates or an association with brain development if there was family functioning earlier on.”
Researchers asked mothers and any participating fathers to independently rate family relationships at different time points using a well-established questionnaire called the Family Assessment Device. Once the children in the study turned 10, their emotional and behavioral health was documented using the Child Behavior Checklist, and their brain images were collected using a 3-T magnetic resonance imaging system.
Tiemeier said he decided to focus on the hippocampus and the amygdala, two structures in the brain, due to their role in emotion and memory regulation.
“[The hippocampus] does many things, but it is most known for its cognition. So it really decides about memory and commission,” Tiemeier said. “And the amygdala next to it is much more involved in emotion, and some would say also emotional memories.”
However, contrary to their hypothesis, the study did not find a correlation between poor family functioning and amygdala size.
Tiemeier said that he hopes his research will emphasize the importance of studying parental psychopathology and more generally the social environment of child psychiatry.
“I felt that much of child psychiatry has moved away from family functioning and factors in the environment and focuses very much on the biology, both in treatment and in explaining it to families,” he said. “We should focus much more on the environment, the family environment, and not medicalize that.”
University of Vermont professor Jim Hudziak echoed many of the implications of Tiemeier’s study on the field of child psychiatry. Hudziak described Tiemeier’s findings as a “call to arms.”
“What Tiemeier et al. have done is show something that is not surprising, and in my own opinion, should be a call to arms for all of us,” Hudziak said. “Smaller hippocampus volumes have a doubtless impact on the function of the hippocampus. And its sub-components make it more difficult for children to regulate their emotions and more difficult for them to perform in academic settings.”
Tiemeier said that in the future, he wants to study not only how social factors — both within and outside of the family — impact the brain, but also what determinants can help overcome both physical and emotional stressors.
“My main goal is to understand how your own behavior shapes all of these processes together, because I think we can see — and that's a very radically different approach — behavior of children much different than adults,” Tiemeier said. “You do shape your brain much more at that age, as like a training thing that helps your behavior also down the road.”
— Staff writer Andy Wang can be reached at firstname.lastname@example.org.