Early exposure to harsh parenting during preschool years can have widespread effects on the organization of the entire brain’s communication. Later exposures affect specific brain areas.

A new University of Michigan study published in JAMA Pediatrics highlighted how harsh and warm parenting during early, middle and late childhood impacted brain development during adolescence and how these changes predicted later mental health.

Researchers used a new statistical method to identify whether there are “sensitive periods” in childhood when the brain is particularly susceptible to external influences and whether experiences during these sensitive periods would predict mental health during a stressful period like the COVID-19 pandemic. They also used advanced brain imaging techniques to explore how information flows through the developing brain.

“Understanding these sensitive periods can inform more effective policy and intervention strategies,” said Luke Hyde, U-M professor of psychology and faculty associate at the Institute for Social Research.

Cleanthis Michael, a U-M graduate student and the study’s first author, says the “findings indicate that earlier interventions may offer broader benefits for brain development.”

Data came from a 21-year longitudinal birth cohort study of low-income youths and families from Detroit, Chicago and Toledo, Ohio. The data, which originated from the Future of Families and Child Well-being Study, were collected from February 1998 to June 2021. The current study sample includes an analysis of 173 youths.

Parents reported their harsh behavior—psychological and physical aggression—and observers recorded warm parenting (responsiveness) for children at ages 3, 5 and 9. A follow-up substudy with neuroimaging was done for youths at age 15. Six years later, during the COVID-19 pandemic, participants reported their symptoms of anxiety and depression.

The findings indicated parents’ harsh parenting during early childhood affected the overall organization of the brain in adolescence. However, harsh parenting in late childhood more specifically affected the corticolimbic circuit—a specific part of the brain that includes the amygdala and frontal cortex and is involved in processing and regulating emotion.

The researchers also examined positive aspects of parenting and found that warm parenting during middle childhood was associated with how the amygdala, a small part of the brain involved in emotion and processing threats, was differentially connected to other parts of the brain. Importantly, parenting warmth predicted reduced anxiety and depression 15 years later during the COVID-19 pandemic due to its effects on the amygdala.

Hyde says the research shows that the impact of positive and negative experiences on the brain may be different depending on when in life we have these experiences.

“It uses new methods to test age-old questions from developmental psychology about whether children have sensitive periods of brain development,” he said.

Michael says that “because these experiences seemed to affect later risk for depression and anxiety, this research highlights periods of vulnerability and opportunity for treatments and policy to promote healthy, long-term development. Interventions for parents, and policies that support parents, may have more profound impacts earlier in life.”

The study’s other co-authors are Arianna Gard, Scott Tillem, Felicia Hardi, Erin Dunn, Andrew Smith, Vonnie McLoyd, Jeanne Brooks-Gunn, Colter Mitchell and Christopher Monk.

National Institute of Mental Health (grants R01MH103761, R01MH121079) and the National Institute of Child Health and Human Development (grants R01-HD36916, R01-HD39135, U01-HD110063, and R01-HD40421)