child stress
June 28, 2014

Childhood Abuse And Poverty Can Lead To Adult Health And Behavioral Issues

redOrbit Staff & Wire Reports - Your Universe Online

Chronic stressors such as poverty or abuse can have a lasting negative impact on children and could be linked to behavioral, health or employment-related problems later on in life, according to new research appearing in the latest edition of the journal Biological Psychiatry.

While experiencing a certain amount of stress can help youngsters learn how to adapt to and cope with life’s obstacles, researchers from the University of Wisconsin-Madison report that long-lasting, toxic stress such as growing up in poor conditions, being neglected or even physically abused can have lasting harmful effects.

In their new paper, the study authors demonstrate how these types of early-life stressors could alter the parts of the brain responsible for learning, memory and the processing of stress and emotion in developing children. Those changes could be tied to negative impacts on behavior, well-being and even the choice of romantic partners in life.

“We haven't really understood why things that happen when you're 2, 3, 4 years old stay with you and have a lasting impact,” co-lead researcher and UW-Madison psychology professor Seth Pollak said in a statement. “Given how costly these early stressful experiences are for society… unless we understand what part of the brain is affected, we won't be able to tailor something to do about it.”

Early life stress has previously been linked to depression, anxiety, heart disease, cancer, and a lack of educational and employment success, Pollak explained. The findings could be important for economists, epidemiologists, public policy makers and others, added lead author and recent Wisconsin PhD graduate Jamie Hanson.

As part of their research, Hanson, Pollak and their colleagues recruited 128 children approximately 12 years old, each of whom had suffered physical abuse, early-life neglect or had come from low socioeconomic status homes.

The study authors conducted in-depth interviews with both the children and their caregivers, documenting behavior issues, and compiling a list of stressful life events. They also took images of each youngster’s brain, focusing specifically on the regions involved in emotion and stress processing, the hippocampus and the amygdala.

The results were compared to children who were similar in age, but who came from middle-class households and had not been mistreated while growing up. Hanson’s team outlined the hippocampus and amygdala of each child by hand and calculated their volumes, choosing not to use computer-based measurements due to the potential for error.

Those hand-based measurements revealed that children who had experienced any of the three types of early-life stress had smaller amygdalas than those who reported no such experiences. Likewise, kids from low socioeconomic status households and those who had been physically abused had smaller hippocampal volumes, according to the UW-Madison research team. Running those same images through automated software revealed no effects.

Pollak, who also serves as the director of the UW Waisman Center's Child Emotion Research Laboratory, called the findings “an important reminder that as a society we need to attend to the types of experiences children are having. We are shaping the people these individuals will become.”

However, he and Hanson explain that the results of their study are only markers for neurobiological change, demonstrating how the human brain and biology can be altered but not a way to predict the impact that a person’s past will have on his or her future. “Just because it's in the brain doesn't mean it's destiny,” noted Hanson.

Image 2 (below): Different forms of early life stress, such as child maltreatment or poverty, impacted the size of two important brain regions: the hippocampus (shown in red) and amygdala (shown in green), according to new University of Wisconsin–Madison research. Children who experienced such stress had small amygdalae and hippocampai, which was related to behavioral problems in these same individuals. Credit: Jamie Hanson and Seth Pollak