Four experiments studied the perception of the unity and boundaries of objects by 88 4-month-old infants who manipulated them out of the visual field. Infants perceived the unity/boundaries of these objects by detecting the motion patterns they themselves produced. Discrimination between motion patterns transferred from touch to vision. (SLD)

The conceptual categories that children have developed in their second year were studied in five experiments using object manipulation tasks. Subjects included 152 children from 18 to 31 months of age. These very young children had formed global conceptions of many domains of objects. (SLD)

The contrast between holistic and differentiated perception of multidimensional stimuli is reconceptualized. Hypotheses about the experiential status of dimensions within holistic perception were tested as explanations of children's general perceptual mode and of adults' integral mode. Three levels of dimensional status are described. (Author/RD)

Six experiments involving 262 children (as young as 16 months and as old as fifth grade) indicate that the basic framework for coding location is present early in life and that later development consists of an increasing ability to impose organization on a broad range of bounded spaces. (SLD)

Four experiments examined the flexibility and stability with which children and adults organize locations into categories based on their spatiotemporal experience with locations. Seven-, 9-, 11-year-olds, and adults learned the locations of 20 objects in an open, square box. During learning, participants experienced the locations in four…