Child development researchers are asking the question: Is the pandemic shaping children's brains and behaviors?
Like many pediatricians, when COVID-19 cases first surged in Dani Dumitriu's ward, she was prepared to deal with its impact. At Morgan Stanley Children's Hospital in New York-Presbyterian Church, where most newborns exposed to the dangers of COVID-19 seem to be safe and sound, she breathes a sigh of relief — some viruses, such as Zika, cause birth defects, so doctors were once worried that COVID-19 would cause the same problem.
But with that comes a more subtle trend. Dumitriu and her team have more than two years of infant developmental data, and since late 2017 they have been analyzing communication and motor skills in infants under 6 months of age. Dumitriu thought it would be interesting to compare the results of babies born before and during the outbreak. She asked her colleague, Morgan Firestein, a postdoctoral researcher at Columbia University, to assess whether there were neurodevelopmental differences between the two groups.
A few days later, Fairstein panicked and called Dumitriu. "She said, 'We were in crisis and I didn't know what to do because we were not only affected by the pandemic, but it was a lot,' Dumitri recalled. That night, she barely slept, studying the data carefully. Babies born during the pandemic scored on average on the Big Movement, Fine Motor and Communication Skills tests compared to babies born before the pandemic (parents of both groups were assessed using an established questionnaire). It doesn't matter if their biological parents are infected; it seems to be related to the circumstances of the outbreak itself.
Dumitriu was stunned. "We shouted at the time, 'Oh my God,'" she recalled. "We're talking about hundreds of millions of babies."
While children are generally in good shape when infected with the coronavirus, preliminary research suggests that outbreak-related stress during pregnancy may have a negative impact on the brain development of some fetuses. In addition, parents and caregivers may interact less with younger children when they are too tired, which can affect the child's physical and psychological abilities.
Lockdowns are critical to controlling the spread of COVID-19, but it has also led to many young families facing quarantine, depriving them of playtime and social interaction. Because of the stress and lack of skills, many parents are unable to provide one-on-one care for babies and young children.
"Everyone wants to document the impact this has on child development, parent-child relationships and peer relationships," said James Griffin, director of the National Institute for Child Health and Human Development. "Everybody's worried."
Around the world, some teams are starting to publish their findings. It's hard to get a consistent answer, especially since many child development research labs have closed during the pandemic.
Some babies born within the past two years may experience stunting, but others may thrive if caregivers stay home for extended periods of time and there are more opportunities for interaction between siblings. As with many aspects of health during the pandemic, social and economic disparities play a clear role. Early data suggest that the use of masks did not have a negative impact on children's emotional development. But prenatal stress can cause some changes in brain connections.
Some researchers have proposed that many children who are lagging behind in development will be expected to catch up. Moriah Thomason, a child and adolescent psychologist at NYU Grossman School of Medicine, said: "I don't think there will be a generation that will be hurt by this outbreak. ”
Infant brain development is decreased
During the COVID-19 pandemic, brown university's advanced infant imaging laboratory remained open. Medical biophysicist Sean Deoni and his colleagues used MRI and other techniques to study how environmental factors affect infants' brain development, tracking their motor, visual and language skills.
As the outbreak progressed, Diony began to hear worrying comments from his colleagues. Dioni recalls: "Our employees started telling me, 'Oh my God, it's going to take longer for these kids to get through the assessment.' ’”
He was confused, so he asked his researchers to plot and compare the annual mean and variance of the baby's neurodevelopment scores. As a result, they found that the scores during the epidemic were much worse than those in previous years. In a set of tests that measure development in a similar way to IQ tests, babies born during the pandemic scored nearly two standard deviations lower than babies born before. They also found that infants from low-income families declined the most, with boys being more affected than girls and large motor skills the most affected.
At first, Deoni thought the choice bias was at work: perhaps families struggling to get tested during the pandemic were those whose children were at risk of developmental problems or who had already shown such problems. But, over time, he became increasingly convinced that selection bias did not explain the findings, as the children who came to be tested had no significant differences in socioeconomic status compared to previous participants.
These effects appear to be drastic, but some researchers believe they don't necessarily predict long-term problems. Marion van den Heuvel, a developmental neuropsychologist at Tilburg University in the Netherlands, said: "IQ in infancy doesn't predict anything. It's really hard to say what this means for their future. She noted that a study showed that Romanian girls who initially lived in an orphanage but were adopted by foster families before the age of 2 and a half were less likely to have mental problems at age 4 and a half than girls who had been in orphanages. This situation is different from the outbreak, but it shows that once the restrictions are lifted, babies have a chance to catch up.
Worryingly, however, Diony found that the longer the outbreak lasts, the more deficits children accumulate. Speaking of the findings, Dioni said: "It's a huge number, shocking. ”
Assuming these findings do have value, why are babies born during the COVID-19 pandemic likely to experience severe cognitive impairments, especially movement disorders? Dioni suspects that these problems stem from a lack of human interaction. In a follow-up study that has not yet been published, he and his team documented parent-child interactions at home and found that the number of parents and children talking has decreased in the past two years compared to previous years, and vice versa. He also suspects that infants and toddlers don't get as many big muscle exercises as they used to, because now they have fewer opportunities to play with other children or go to the playground. "Unfortunately, these skills somehow lay the foundation for other skills," he said.
Other recent studies also support the idea that a lack of peer interaction may hinder the development of some children. In a study published earlier this year, researchers in the UK surveyed 189 parents of children aged 8 months to 3 years, asked whether their children had received day care or preschool education during the pandemic, and assessed language and executive function skills. The authors found that children's skills would be stronger if they received group care during the pandemic, and these benefits were more pronounced among children from low-income families.
The most dangerous appears to be children of color or children from low-income families. For example, a growing body of research suggests that distance learning among school-age children may be widening the already large learning and development gap between wealthy and low-income families, white children and children of color. In the Netherlands, the researchers found that children performed worse in the 2020 national assessment compared to the previous three years, while children from less educated families lost up to 60 percent of their learning.
Effects of wearing a mask
During outbreaks, children in school or other group settings often interact with people who wear masks. An important question is whether masks mask mask parts of the face that are important for expressing emotions and language, and whether it can also affect a child's emotional and language development.
Edward Tronick, a psychologist at the University of Massachusetts, has been bombarded with emails from parents and pediatricians who worry about the impact masks could have on development. Tronik is best known for his 1975 "Still Face" experiment, which showed that when a biological parent suddenly made a face while interacting with a baby, their children initially tried to get their attention and then became increasingly upset.
Tronik decided to see if the mask had a similar effect. He and his colleague, psychologist Nancy Snidman, conducted an experiment (not yet peer-reviewed) in which parents used smartphones to record infant interactions with them before, during, and after wearing masks. Although babies notice that when their parents put on masks, they briefly change their facial expressions, look away or point to the mask, they continue to communicate with their parents as before. Tronik said masks block only one communication channel. "Parents wearing masks are still saying, 'I'm communicating with you, I'm still here to support you, I'm still in touch with you.'" ”
Masks also don't seem to cause much interference with emotional or verbal perception. A study published last May reported that children as young as two can still understand what adults wearing opaque masks say. Leher Singh, a psychologist at the National University of Singapore and lead author of the study, said children "compensate for missing information more easily than we think". Researchers in the United States have found that although wearing masks makes it harder for school-age children to perceive adult emotions, in most cases, children are still able to make accurate inferences.
Pregnant women and stress
Other researchers are eager to know whether the outbreak will affect children's development before birth. At the University of Calgary in Canada, psychologist Catherine Lebel surveyed more than 8,000 pregnant women during the pandemic. Nearly half reported symptoms of anxiety, while one-third had depressive symptoms — a rate much higher than in previous years of the pandemic. How does this stress affect the baby in the womb?
To find out, the researchers scanned the brains of 75 babies 3 months after they were born using MRI. In a preprinted report published in October, they found that babies born to people who had more anxiety or depressive symptoms before childbirth had different structural connections between their amygdalas (areas of the brain involved in emotional processing) and the prefrontal cortex (the area responsible for performing functional skills).
Brain scans show average patterns of connectivity between the baby's amygdala and other regions. The pressures associated with the outbreak during pregnancy have weakened the connectivity of some babies.
In a previous small study, Lebel and her team have linked prenatal depression to differences in brain connections in these areas and proposed that in boys, these brain changes are associated with aggressive and hyperactive behaviors before age 12. Other teams have found that changes in the connections between these areas in the adult brain are risk factors for depression and anxiety. "These areas involve emotional processing and many different behaviors," Lebel said. ”
Thomasson is conducting her own research to assess the effects of a mother's stressors on a child's brain and behavior. She noted that while there are many concerns that prenatal stress may affect covid-19 babies, early detections such as these do not mean that children will struggle for the rest of their lives. "Kids have great adaptability and resilience. We expect the situation to improve," she said.
Caution and action
Studies of covid-19 babies present a mixed picture, and scientists say it's too early to come up with a meaningful explanation. Catherine Monk, a medical psychologist who works with Dimitriu, says these early, often unpublished findings may not reflect reality.
Dimitriu pointed out that even if children's brains are really affected by the epidemic, there is still time to guide them back on track. "We can well get ahead of this before it becomes a public health emergency," she said. "The brains of 6-month-old babies are so malleable that we can go into it and change their trajectory."
Parents can make progress by playing and talking to their children more. Policy changes aimed at supporting families and children will also have an impact. Lebel's research found that meaningful social support during pregnancy, such as support from a partner or close friend, greatly reduces prenatal troubles.
Overall, the researchers believe that most children may be fine, but there may be more children struggling at the moment. Dioni said: "The children are of course very adaptable. But at the same time, we recognize that the first 1,000 days of a child's life are crucial early foundations. "The first outbreak babies born in March 2020 are now over 650 days old.
Dioni said children are "a product of the environment." "The more we play with them, read to them, and love them, the more we inspire them to grow – that's what we're going to do."
Compilation: Juan
Edit: Gangnam
Source: Nature Journal, New York Time