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)

Discusses developmental changes in visual exploration and manipulative investigation among children from birth to six months, six to 12 months, and 12 to 36 months of age. Also discusses pretend play in terms of decentration, decontextualization, and integration. (RH)

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)

Explores the relation between the infant's ability to negotiate the environment and the quality of the infant-mother attachment relationship. (HOD)