Member-only story
Child Proof
What Peekaboo Teaches Kids About the World
Researchers say hiding games play an essential role in child development

You cover your face with a blanket, then uncover it to see your baby’s reaction. Cover. Uncover.
Two years later, your toddler is standing in front of you with her hands over her eyes, yelling “Can you see me?” for roughly the hundredth time in a row. It’s cute and mind-numbing parental labor — and it says more about your child’s brain development than you might guess.
“Peekaboo surely must rank as one of the most universal forms of play between adults and infants,” wrote cognitive psychologist Jerome Bruner with a colleague in 1976. Researchers have studied peekaboo games from South Africa to Germany to Japan (where a parent might chant “Inai inai ba!”), using the ubiquitous game to look at children’s smiles, laughter, expectations, and perception of others’ emotions. They’ve even studied the brain activity of nine-month-olds during a game of peekaboo.
Iris Nomikou, a linguist in the Psychology Department at the University of Portsmouth in the United Kingdom, has found the hiding game to be a powerful window into the developing mind. In a 2017 paper, Nomikou and her colleagues made video recordings of Polish mothers playing peekaboo (“A-ku-ku!”) with their babies at four and six months old. The older infants were more engaged in the game, but even as early as four months, babies made some attempts to participate — by reaching for a cloth covering the mother’s face, for example. And babies’ smiles and vocalizations didn’t come at random times but were more likely to happen at certain moments, such as smiling when Mom’s face reappeared.
Peekaboo is “like a dialogue,” Nomikou says. (Other researchers have called it a “protoconversation.”) “We sort of assume that these kinds of interactions are key for language development.” The game has a predictable back-and-forth, which the infants in the study seemed to learn over time; Nomikou saw that babies were more likely to participate when mothers made space for them by pausing and waiting. Inviting a baby to participate in the game, rather than just observe, she says, may be a powerful factor in the child’s development.