Studies 12- to 24-month-olds in a series of videotaped tasks assessing single object manipulation, relational play, pretend play, distractibility and persistence. Develops eight relatively subtle measures of three aspects of individual differences in infant behavior: developmental level, attention span, and exploratory diversity. (Author/NH)

Reports two studies of infant exploration. In the first, age and characteristics of the object stimuli influenced 6-, 9- and 12-month-olds who manipulated a series of objects. Results of the second study suggested that different kinds of manipulation are used to explore changes in shape, texture, and weight. (Author/CB)

Studied the early development of exploratory behavior in 99 infants of 2-5 months. Results show that there are significant changes in spontaneous multimodal exploration of a novel object between 2 and 5 months. (RJC)