Long-term stress can lead to problematic parenting, according to researchers who observed how mothers who are poor and those with depressive symptoms interacted with their toddlers.
"Stress gets under your skin," said lead researcher Melissa Sturge-Apple, assistant professor of psychology at the University of Rochester. "It literally changes the way a mother's body responds to the normal demands of small children and those changes make it much harder to parent positively."
Moms with higher levels of depressive symptoms had overactive stress responses when interacting with their children, and they showed the highest levels of hostility, including derogatory comments, angry tone of voice and rough physical interaction, according to the researchers.
Meanwhile, mothers living in poverty had underactive stress responses, and they were more likely to ignore their children's desire for attention or play, but when they did become engaged, these mothers were overbearing, the researchers found.
The corrosive effects of stress are no surprise, but this study's findings highlight the physical and behavioral effects of poverty and depression, according to the researchers.
"Stress is not just in our heads, it's in our bodies," Sturge-Apple said.
The researchers observed 153 mothers with their 17- to 19-month-old toddlers in two situations. The researchers used a wireless monitor to track subtle changes in the mothers' heart rhythms during a mildly stressful situation when her child was left with a stranger for a few minutes. The mother and the toddler were later observed together during unstructured playtime. [ Top 5 Benefits of Play ]
Moms with depressive symptoms and hyperreactive stress responses had higher heart rate patterns to begin with, but these patterns spiked in response to their toddler's distress. Even after mother and child were reunited, the mother's heart rate remained elevated.
Depression is linked to harsh, highly reactive parenting, according to Sturge-Apple.
On the other extreme, mothers living in poverty and in high-crime areas showed underactive stress responses, with heart rate patterns that started out lower and increased little when their children became upset.
Faced with threats and concerns on a daily basis, these moms' stress systems simply become overwhelmed, according to Sturge-Apple.
The research appeared online recently in the journal Development and Psychopathology.
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