Migrant Family Separation Congressional Testimony: Dr. Jack P. Shonkoff



February 7, 2019

 Oral Testimony
Jack P. Shonkoff, M.D.
Director, Center on the Developing Child at Harvard University.
Julius B. Richmond FAMRI Professor of Child Health and Development,
Harvard T. H. Chan School of Public Health and Harvard Graduate School of Education.
Professor of Pediatrics, Harvard Medical School and Boston Children’s Hospital.


Good afternoon. Chair DeGette and Ranking Member Guthrie, thank you for the opportunity to meet with you today.

My name is Jack Shonkoff. I am Director of the Center on the Developing Child at Harvard University, Professor of Child Health and Development at the Harvard Chan School of Public Health and Graduate School of Education, and Professor of Pediatrics at Harvard Medical School and Boston Children’s Hospital. I am a pediatrician by training and my work is focused on early life influences on learning, behavior, and health.

View Dr. Shonkoff’s oral testimony.

My testimony today is based on strong scientific consensus supported by decades of peer-reviewed research. Sudden, forcible separation of children from their parents is deeply traumatic for both the child and the parent. Above and beyond the distress we see “on the outside,” this triggers a massive biological stress response “inside” the child, which remains activated until the parent returns and provides comfort. Continuing separation removes the most important protection a child can possibly have to prevent long-term damage—a loving adult who’s totally devoted to his or her well-being.

Without exaggeration, thousands of studies converge on the following two core scientific concepts:

  1. A strong foundation for healthy development in young children requires a stable, responsive, and supportive relationship with at least one parent or primary caregiver.
  2. High and persistent levels of stress activation (known as “toxic stress”) can disrupt the architecture of the developing brain and other biological systems with serious negative impacts on learning, behavior, and lifelong health.

Early experiences are literally built into our brains and bodies. Stable and responsive relationships promote healthy brain architecture, establish well-functioning immune, cardiovascular, and metabolic systems, and strengthen the building blocks of resilience.

If these relationships are disrupted, young children are hit by the “double whammy” of a brain that is deprived of the positive stimulation it needs and assaulted by a stress response that disrupts its developing circuitry.

When any of us feels threatened, our body’s stress response systems are activated. Heart rate and blood pressure go up, stress hormone levels are elevated, blood sugar rises, and inflammatory responses are mobilized. This is the “fight or flight” response. We all know what that feels like physically when we’re really stressed out!

This response is automatic and essential for survival, but it is designed to go back to normal when the threat is over. If the sense of danger continues, ongoing activation of the stress response shifts from protection to disruption or outright damage. For example:

  • Persistently elevated stress hormones can disrupt brain circuits that affect memory and the ability to focus attention and regulate behavior.
  • Excessive inflammation and metabolic responses to stress in childhood increase the risk of heart disease, diabetes, depression, and many other chronic illnesses in the adult years.

Unlike “positive” or “tolerable” stress, which can build resilience, the excessive and prolonged nature of what we call “toxic stress” increases the risk of lifelong problems.

The scientific principles I have just described provide a powerful framework for understanding the damage caused by the current family separation policy. All children who were abruptly separated from familiar caregivers at the border experienced overwhelming stress. Will some survive without significant problems? The answer is yes. Will many be seriously impaired for the rest of their lives? The answer again is yes. The biology of adversity suggests three factors that influence who is at greatest risk.

The first is age. Younger children are the most vulnerable because their brain circuitry and other biological systems are relatively under-developed, and because they are most dependent on adult caregivers.

The second is previous harm from adversity. The pile-up of stress on children who are already compromised shifts the odds against them even further. Intentionally withholding the most powerful healing intervention we could possibly offer—the care that parents provide when their children are in danger— goes against everything science tells us.

The third reason for variation in outcomes is the duration of separation. Toxic stress is a ticking clock—and prolonged separation inflicts increasingly greater harm as each week goes by.

From a scientific perspective, the initial separation and the lack of rapid reunification are both indefensible. Forcibly separating children from their parents is like setting a house on fire. Prolonging that separation is like preventing the first responders from doing their job.

Chair DeGette and Ranking Member Guthrie, this concludes my oral testimony. I am happy to answer any questions that you or your colleagues may have. Thank you.

Additional Resources

Peer-Reviewed Literature on the Science of Child Health and Development and the Biology of Adversity

More Resources on Toxic Stress

More Resources on Child Maltreatment and Neglect


More resources on this topic

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