Preschoolers' construction order of event sequences related to mental ability and degree of familiarity.

Preschoolers' understanding of sequential relations was investigated in two experiments. Experiment 1 showed that appreciation of sequential relations depends on the level of mental ability and the degree of familiarity displayed with the social or behavioral phenomena under investigation. Experiment 2 reproduced the findings of Experiment 1 and, further, demonstrated that an increase in experience and familiarity through an interaction phase between children with higher and those with lower mental abilities led to a significant exchange of information and performance that was retained over the posttest phase. The data of both experiments are discussed within the framework of the "invariance hypothesis" (Bullock, 1985) in contrast to Piagetian theory (Piaget, 1946/1969).