The Development of Search Behavior in Infancy and Early Childhood.

The information-processing skills underlying early search behavior were examined in two studies. One study was done with infants 9 and 16 months of age; the other with children 2, 2 1/2, and 4 years of age. The experimental task for both studies was based on Piaget's Stage IV object permanence task. In the infant study, children were given either hiding experience, finding experience, or both hiding and finding experience with a target object at one of three locations. This experience constituted a source of "prior" information about the object's location. Subsequently, the object was hidden at a different one of the three locations. The hiding was done either in full view of the infant or behind a screen. When the hiding was visible it was constituted a source of "current" information. The preschool study included all of the conditions from the infant study. In addition, two new forms of information were introduced that could not be used with infants. On some trials, current information was provided verbally instead of by allowing children to watch the object being hidden at the second location. Also, sometimes prior information was provided by using target objects and locations that were differentially associated with each other (e.g., pillow-bedroom) instead of by providing any specific experience at an initial location. The results of the two studies indicated that even the youngest infants were able to use information derived from watching as the object was hidden as a basis for search, but use of more indirect sources of information emerged only at the older ages. Use of prior information from experience at an initial location was evident by 16 months of age. Verbal information was used to some extent by the 2-year-old, but it was used more consistently by the older two age groups. Only the 4-year-olds showed reliable use of the information provided by using target objects and locations that were differentially associated. Further age differences emerged in the way children responded to conflicts between alternative sources of information. As early as 16 months of age, children showed some selectivity in their use of information, in that they gave precedence to current over prior information when the two were in conflict. However, selectivity continued to increase over the preschool years. There was no evidence of systematic perseveration at 9 months of age, contrary to Piagetian theory. However, perseveration was observed at older ages. This perseveration appeared to be more sophisticated than the Piagetian account implies, and it was necessarily incompatible with selective information use.Ph.D.Developmental psychologyUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/157999/1/8025774.pd