Devised by Jean Piaget (1896-1980) to investigate the development of object permanence in infancy, the task involves hiding a desirable object at location A for several trials and then hiding it at a new location B. The error is that infants below about 12 months perseverate in searching at A from where they have successfully retrieved the object several times, sometimes even when the object is visible at the new location B. Introducing a delay imposed between the moment the toy is hidden and the reaching action is initiated before allowing the infant to search increases the difficulty of this task, resulting in perseveration, and suggesting that short-term (working) memory constraints have to be overcome in order to perform the task correctly. Thus, the task requires infants both to hold a retrieval plan in mind, and to suppress a previously reinforced response.
See Inhibitory control, Object permanence, Mental image, Search errors in infancy, Working memory