Baby Eyewitness

Can infants be traumatized by the sight of violence?

Do infants remember a horrific event?

An employee of the U.S. consulate in Ciudad Juárez, Mexico, and her husband were shot to death in their car Sunday. The victims’$2 7-month-old daughter was found crying, but unharmed, in the back seat. Will witnessing her parents’ murder at the hands of narco-mobsters have any long-term effects on the baby?

Probably. Even a baby is capable of perceiving the cataclysmic nature of the scene that unfolded in Ciudad Juárez: loud noises, blood, and the distorted faces of her parents. When confronted with traumatic events like car accidents and terrified parents, babies manifest a classic stress response, with increased heart rate, blood pressure, and respiration. In general, the familiar smell and sound of a baby’s mother and father would mitigate these effects; without that solace, she might remain on edge for a prolonged period. Extended stress can yield long-term physical effects: An ongoing landmark study of 17,000 patients beginning in California in the 1990s has shown that people who suffered serious trauma—e.g., physical abuse or the loss of a parent—during early childhood are 6 to 12 times more likely to experience heart disease, stroke, diabetes, and cancer. Doctors theorize that the victims’ bodies become more reactive to stress as a result of these formative episodes, and simply wear out faster.

A baby might be very disturbed by the sight of a dead body, even without any understanding of what it means to be killed. Developmental psychologists have used a set of “still-face experiments” to show how infants behave in the presence of a nonresponsive parent. A mother is asked to stare down her 3- to 6-month-old baby with no emotion showing on her face whatsoever. The baby tries various behaviors to get the mother to react, including laughing, pointing, and chattering. When the mother fails to respond, the baby almost always becomes despondent or cries furiously.

However upset the infant in Mexico might have been at the time, she won’t be able to recall any details of her parents’ murder when she gets older. Children can’t create conscious memories until around two years of age. Still, there’s reason to believe that trauma can be stored in the brain as “implicit memories.” For example, a baby who witnessed the murder of a family member with a hammer might experience an accelerated heart rate when shown a hammer several months later. Adults have been known to associate smells or tunes with grandparents who died during their early childhood. (Not all psychologists believe these memories are real. It might be that what appear to be early-life associations only develop after the fact on the basis of secondhand information.)

Is there any way to treat infant trauma? In the short term, therapists will try to establish a tight bond between the Ciudad Juárez baby and her replacement caregivers. They will observe the family at play and encourage the new parents to be responsive to the little girl’s needs. They will also monitor the baby for short-term effects. Some traumatized infants become less expressive of their emotions, perhaps because crying did not trigger a nurturing response during the stressful event. The infant may also have difficulty sleeping and feeding.

In eight months or so, the child may start to re-enact elements of the murder during her play. She might smash toy cars inordinately. When she gets older, she may draw more violent pictures than her peers. Some theorize that this is the child’s way of mastering the event, the same way an adult tends to replay arguments over and over again in their heads, sometimes changing details to reinforce their position.

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Explainer thanks Theodore J. Gaensbauer of the University of Colorado Health Sciences Center, Mark L. Howe of Lancaster University, Joy Osofsky of Louisiana State University Health Sciences Center, Bruce Perry of the Child Trauma Academy, and Charles Zeanah of Tulane University.

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