A new study suggests marital conflict harms children as young as six months by hindering their development of emotional control and their ability to handle stress.
Brigham Young University professor Chris L. Porter discusses relationships between infants' growth and parents' marriage quality in the new issue of the journal "Infancy."
"Just because babies don't talk yet or have limited understanding of social situations doesn't mean they don't react," said Porter, an assistant professor of marriage, family and human development. "This shows that babies are tuned to others' emotions, and that shared emotional experiences impact infants' development as early as the first few months of life."
The findings indicate that high levels of conflict in marriage correlate with immature mental, emotional and physiological adjustment. High levels of love and maintenance in marriage also correlate with strong mental and emotional adjustment. Prior to Porter's study, specific relationships between parents' marriages and physical indicators of stress had only been investigated with preschoolers and school-age children.
"These findings popped up and grabbed our attention," said Porter.
Porter's research included testing 56 six-month-old infants for levels of mental, emotional and physiological development, and then surveying the infants' mothers to measure levels of love, conflict, ambivalence and maintenance in their marriages.
To assess the physiological development of each child, Porter and his student research assistants measured vagal tone, named after the vagus nerve, which indicates the nervous system's control of heart rate and an individual's ability to adjust physically to stress.
"Vagal tone measures the capacity of the body to calm itself," Porter said. "It tells us how prepared a person is to meet stressful challenges."
Infants' mental and emotional levels were also rated using standardized tests involving simple tasks and interaction with objects. While the infants participated, observers recorded emotional display, such as adaptability and irritability. Infants from high conflict marriages scored lower than expected in vagal tone, mental development and emotional regulation. Porter proposes that this is likely a result of repeated exposure to stress, such as arguments by parents.
"Conflict that remains unresolved leads to problems for children," Porter said.
As children in high-conflict situations grow up, the effects may be displayed externally by children acting out, becoming aggressive and defiant, Porter said. In another common scenario, the effects are internalized and children become sad, depressed and withdrawn.
"These kids may also have difficulty taking initiative and becoming social leaders," Porter said. "The key for parents is how well families deal with conflict."
Besides direct exposure to conflict and stress, another explanation Porter offers is that parents in continual discord are perhaps less available to their children emotionally, limiting the opportunity for stimulating social exchanges that tend to enhance children's development.
"Development does not happen in a vacuum, it occurs in the context of relationships," Porter said.
Porter also cautioned that the study found a correlation, but did not definitively establish which behavior causes which outcome. It's possible, he noted, that infants with poor abilities to deal with their emotions may cause stress within their parents' marriages.
The report is co-authored by BYU graduate students Melissa Wouden-Miller, Staci Shizuko Silva and Adrienne Earnest Porter, who has since completed her graduate study.
Writer: Joseph Hadfield