It’s three in the morning and the baby is still crying. After checking that he is fine, that he is not hungry and that his diaper is dry, his parents resort to all possible tricks to calm the little one and fall asleep, among which rocking, lullabies, lullabies and the last of the options: the car ride. But the nocturnal temper tantrum continues and the nerves start to get truncated.
A group of Japanese scientists claim to have discovered the formula to end this frustration experienced by most parents. They explain their strategy in the journal ‘Current Biology’ and it is so simple that it will probably seem disappointing to some, but there is nothing stopping you from trying it. As they write, to calm a crying baby, you should do the following: walk with the baby in your arms for five minutes; sit with the little one on top for five to eight minutes, then, when the goal is achieved, calmly place him in his crib. It’s easy. And they say it works.
“Many parents experience nighttime crying in babies,” says Kumi Kuroda of the RIKEN Center for Brain Science in Japan and author of the study. “This is such a big problem, especially for inexperienced parents, that it can lead to stress and even child abuse in a small number of cases,” he notes.
Kuroda and his colleagues studied the transport response, an innate reaction observed in many altricial mammals, those whose young are immature and unable to care for themselves, such as mice, dogs, monkeys and humans. . They observed that when these animals pick up their young and start walking, their young’s bodies tend to become docile and their heart rate slows. Kuroda’s team wanted to compare the effects of the carrying response – the relaxed reaction during carrying – with other conditions, such as holding or rocking the infant with the mother still, and also to examine whether the effects persist with a longer carriage in infants. .
The researchers compared the responses of 21 babies while they were in four conditions: being held by their walking mother, being held by their sitting mother, lying in a still crib or lying in a rocking crib. The team found that when the mother walked holding the baby, crying babies calmed down and their heart rate dropped within 30 seconds. A similar soothing effect occurred when babies were placed in a rocking crib, but not when the mother held the baby in a sitting position or placed the baby in a stationary crib.
This suggests that simply holding a baby may be insufficient to calm crying, contradicting the traditional assumption that being held by the mother reduces infant distress. At the same time, movement has soothing effects, probably by activating the baby’s carrying response. The effect was most evident when the standing and walking movements were continued for five minutes. All of the crying babies in the study stopped crying and almost half of them fell asleep.
But when mothers tried to put their sleeping babies to bed, more than a third of participants returned to alertness within 20 seconds. The team found that all babies produce physiological responses, including changes in heart rate, that can wake them up as their bodies separate from their mothers. However, if babies slept longer before putting them to bed, they were less likely to wake up during the process, the team found.
“Even as a mother of four children, I was very surprised to see the result. I thought that the awakening of the baby in the cradle was linked to the way he positioned himself in the bed, such as his posture or the softness of the movement,” explains the researcher. “But our experience has not confirmed these general hypotheses,” he adds. While the experiment only involved mothers, Kuroda expects the effects to be similar in any caregiver.
Based on their findings, the team proposes a method to calm and promote sleep in crying babies. They recommend that parents hold and walk babies for five minutes, then sit and hold babies for another five to eight minutes before putting them to bed. The protocol, unlike other popular sleep training approaches such as letting babies cry themselves to sleep, aims to provide an immediate solution to crying babies. Whether it can improve infant sleep in the long term needs more research.
“Many of us intuitively breed and listen to others’ advice on parenting without testing the methods with rigorous science. But we need science to understand a baby’s behaviors because they are much more complex and diverse than we thought,” says Kuroda.