Provocative new research suggests marital conflict is a significant source of environmental stress for children.
Witnessing parents fighting may harm children’s stress response systems. In turn, the impaired stress response may affect a child’s mental and intellectual development, say Auburn University and the Catholic University of America researchers.
In the study, scientists looked at 251 children from a variety of backgrounds who lived in two-parent homes.
The children reported on their exposure to marital conflict when they were 8, providing information on the frequency, intensity, and lack of resolution of conflicts between their parents.
Researchers evaluated how children’s stress response system functioned by measuring respiratory sinus arrhythmia (RSA), an index of activity in the parasympathetic branch of the body’s stress response system.
Prior studies have linked RSA to the ability to regulate attention and emotion.
Researchers also measured children’s ability to rapidly solve problems and quickly see patterns in new information at ages 8, 9, and 10.
Children who witnessed more marital conflict at age 8 showed less adaptive RSA reactivity at 9, but this was true only for children who had lower resting RSA.
Moreover, researchers determined children with lower baseline RSA, whose stress response systems were also less adaptive, developed mental and intellectual ability more slowly.
“The findings provide further evidence that stress affects the development of the body’s stress response systems that help regulate attention, and that how these systems work is tied to the development of cognitive ability,” explains J. Benjamin Hinnant, one of the researchers.
Study findings are published in the journal Child Development.