This study compared role of motion in adults' and infants' perception of object unity. Findings favored ecologically-oriented accounts of object perception. Motion was a determinant of object unity for infants. Alignment and common motion contributed to adults' object-unity perception; synchronous color changes did not. Infants detected…

Addresses two questions that may be unique to perceptual learning: What are the circumstances that produce learning? and What is the content of learning? Suggests a critical principle for each question. Provides a discussion of perceptual learning theory, how learning occurs, and what gets learned. Includes a 121-item bibliography. (DR)

Five experiments used a categorization habituation-of-looking paradigm to investigate infants' categorization of animals and vehicles based on static versus dynamic attributes of stimuli (color images versus dynamic point-light displays). Findings showed that 6-month-olds categorize animals and vehicles based on static and dynamic information, and…