<P> Peekaboo (also spelled peek - a-boo) is a form of play primarily played with an infant . To play, one player hides their face, pops back into the view of the other, and says Peekaboo!, sometimes followed by I see you! There are many variations: for example, where trees are involved, "Hiding behind that tree!" is sometimes added . Another variation involves saying "Where's the baby?" while the face is covered and "There's the baby!" when uncovering the face . </P> <P> Peekaboo uses the fundamental structure of all good jokes--surprise, balanced with expectation . </P> <P> Peekaboo is thought by developmental psychologists to demonstrate an infant's inability to understand object permanence . Object permanence is an important stage of cognitive development for infants . In early sensorimotor stages, the infant is completely unable to comprehend object permanence . Psychologist Jean Piaget conducted experiments with infants which led him to conclude that this awareness was typically achieved at eight to nine months of age . Infants before this age are too young to understand object permanence . A lack of object permanence can lead to A-not - B errors, where children reach for a thing at a place where it should not be . </P>

Why is peek a boo fun for babies
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