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An object is hidden under cover A and an 8-month-old baby is allowed to retrieve it. Then, in full view of the baby, the object is placed under cover B. When allowed to retrieve the object a second time, the baby will typically look under cover A, where the object was found, rather than under cover B, where the baby has just seen it placed.
What is A-to-B error?
If an infant made an “A-not-B error,” Piaget reasoned that children remember the existence of the object but cannot reason systematically about it. Current research implies memory limitations, motor perseveration (repetition of a certain behavior – reaching for A, even if the child looked at B), and capture errors (tendency to use a once-successful solution) may also be reasons why infants fail the A-not-B task.