Raising children is not a stressful job. In fact, it’s causing more anxiety now than ever before. New moms especially have to learn how to deal with new stressors while raising a baby for the first time. So we have to wonder how stress affects parenting for new moms.
In a new study published in the journal Psychoneuroendocrinology, researchers found that higher cortisol levels in new mothers were associated with more intrusive parenting behaviors and increased brain activation in motor planning and auditory processing areas in response to infant cries. was found to decrease.
Essentially, mothers who were more stressed were less likely to guide their babies in their own play and were less responsive to their babies’ cries.
Okay, that was a lot. Let’s start from the beginning.
Collisol is commonly referred to as the “stress hormone” and naturally fluctuates throughout the day. It plays many important roles in the body, including regulating immune function, anti-inflammatory mechanisms, and determining the fight-or-flight response.
Stress causes cortisol levels to rise, but they tend to return to normal quickly. (Despite what you see on TikTok, too high cortisol levels, a symptom of Cushing’s syndrome, are extremely rare, and a healthy baseline varies from person to person.)
However, the study found that higher basal cortisol levels were associated with less positive parenting behaviors. Researchers have previously shown that higher basal cortisol levels are associated with less sensitivity and more intrusive caregiving behaviors in mothers of infants between 3 and 6 months of age.
“Maternal intrusiveness refers to the degree to which a mother follows her child’s lead and waits for uninterrupted entry into interaction,” the study explains.
The researchers’ goal was to understand how cortisol changes maternal brain function and explain why and how these changes are reflected in mothers’ parenting behaviors.
“The goal of this study was to understand how the multiple biological systems that support parenting behavior interact,” said study author Andrew Erhart. Ehrhart is a school-age systems specialist at the Colorado Department of Public Health and Environment and conducted the study as a member of the Family and Child Neuroscience Laboratory at the University of Denver.
“We know that the transition to parenthood is a critical time when the brain and body change to support the development of parenting behaviors. We are interested in understanding how environmental influences moderate biological changes during parenthood.”
The study included 59 primiparous mothers with infants aged 3 to 4 months. These mothers participated in home- and lab-based sessions in which researchers assessed their cortisol levels, their behavior during interactions with their infants, and their brain responses to their infants’ cries.
Researchers observed interactions between mothers and babies at home, without the use of toys. Next, we coded infant sensitivity to cues and non-intrusive behaviors. Researchers collected cortisol samples during the sessions to measure the mothers’ average cortisol levels.
During the lab session, the mothers underwent functional magnetic resonance imaging (fMRI) scans. The researchers played recordings of mothers’ own babies and control babies crying. They then used fMRI scans to measure activity in different areas of the brain in response to infants’ cries.
Home visits revealed a clear link between mothers with high cortisol levels and high stress levels and intrusive parenting.
fMRI scans also revealed that elevated cortisol correlated with decreased brain activity in response to babies’ cries across multiple brain regions. This reduction in brain activity has been linked to more intrusive parenting, and researchers found that mothers with higher cortisol levels may have an impaired ability to respond calmly and effectively to distressed babies. concluded.
But the researchers were surprised to find that the brain effects were concentrated in areas of motor planning and auditory processing, rather than emotional regulation. Further research is needed to understand the relationship between brain function and the behaviors involved in this process.
“Importantly, we are learning more about how our stress system interacts with the mother’s brain when responding to infant cries, and how this relates to parenting behavior. It means that I can now understand it better,” Erhardt said. “Brain regions responsible for motor planning and auditory processing have been found to be less involved in increasing cortisol levels.”
