Researchers have found that most babies — even as young as two months old — know when they are about to be picked up.
The moment their mothers walk toward them with outstretched arms, infants will make their bodies go still and stiff in anticipation, making it easier to be picked up.
This is the first study to examine how infants adjust their posture to offset the destabilizing effect of being picked up.
“We didn’t expect such clear results. From these findings we predict this awareness is likely to be found even earlier, possibly not long after birth,” said Professor Vasu Reddy of the University of Portsmouth.
“The results suggest we need to re-think the way we study infant development because infants seem to be able to understand other people’s actions directed towards them earlier than previously thought. Experiments where infants are observers of others’ actions may not give us a full picture of their anticipatory abilities.”
The findings could also be used as an early sign of certain developmental disorders, including autism. In 1943, researchers found that children with autism didn’t seem to make preparatory adjustments before being picked up.
The researchers conducted two studies — the first on 18 babies aged three months, and a second on ten babies aged two to four months old.
In both studies, the infants were placed on a pressure mat which measured their postural adjustments during three phases: while their mothers chatted with them; while their mothers opened their arms to pick them up; and as the babies were being picked up.
The findings show that babies, as young as two months old, make specific adjustments as mom stretches out her arms. These included extending and stiffening their legs which increases body rigidity and stability, and widening or raising their arms, which helps to create a space for the mother to hold the baby.
Between two and three months of age, the babies’ gaze shifted from mostly looking at their mother’s face to often looking at her hands as they were about to be picked up.
The researchers note two important findings — first, that even as young as two months old, babies make specific postural adjustments to make it easier to be picked up before their mother touches them.
And second, it appears that babies learn to increase the smoothness and coordination of their movements between two and four months, rather than develop new types of adjustment.
“In other words, they rapidly become more adept at making it easier for parents to pick them up,” said Reddy.
Before the actual tests, the mothers in the study were asked about their babies’ physical responses, and some reported that their babies stiffened their legs or raised their arms in preparation for being picked up. But video footage watched frame by frame revealed that physical adjustments happened to a greater degree and more subtly than mothers had noticed.
More research is needed to fully understand how babies discriminate between different kinds of actions directed at them, between familiar and unfamiliar actions, and how infant anticipation of these actions is affected by the different maternal styles they each experience.
The research is published in the journal Plos One.
Source: University of Portsmouth