Describe the development of object permanence

What will be an ideal response?

A good answer will include the following key points:
+ Between 4 and 8 months, infants will neither reach nor search for a hidden object.
+ Beginning at about 8 months, infants search for an object that has been covered by a cloth.
- Infants at this age will commit the A not B error demonstrating that their understanding of object permanence is incomplete at eight to 12 months of age.
+ Infants do not have a full understanding of object permanence until about 18 months of age.