Findings indicate that infants can detect regularity in spatiotemporal series; will develop expectancies for events in the series; and will act on the basis of those expectancies even when their actions have no effect on the stimulus events. (PCB)

Exploratory behaviors of Down Syndrome and nondelayed young children between the mental ages of 16 and 32 months were examined in four situations in which they tried to find things which they saw reflected in a mirror. Down Syndrome and nondelayed children differed in number, type, and frequency of exploratory behaviors. (PCB)

Six experiments were conducted to investigate the sensitivity of one- to four-year-olds to changes in perspective that are occluded from view. Results indicated relatively early sensitivity to proprioceptive cues for changes in perspective and somewhat later sensitivity to appropriate visual-environmental cues. (PCB)

When children with Down's syndrome and normally developing children of comparable mental age were compared in their ability to find things they saw in a mirror, it was found that the ability of children with Down's syndrome paralleled that of normally developing children, but that motivational, attentional, and exploratory differences may exist.…