Three experiments investigated 14-, 18-, and 24- month-old infants' understanding of visual perception. Infants viewed films in which a protagonist was either able to view the location of a hidden object (Visual Access condition) or was blindfolded when the object location was revealed (No Visual Access condition). When requested to find the…

A series of studies focused on (1) the evolution of the notion of identity of objects among infants up to 15 months of age and (2) the changing rules by which this development may be understood. Six identity tasks were presented to 60 infants divided into five age groups: 5, 7, 9, 12, and 15 months. Two objects were used in all tasks. In the first…

The purpose of this study was to cross-sectionally and longitudinally examine the developmental process of search behavior in infancy. Subjects were 23 Japanese normal infants (11 males and 12 females) who were individually tested once a month from the age of six to 13 months in laboratory settings. Small toys and three white opaque cubic boxes…

In four parts, this discussion describes characteristics of the thought of infants, preschool children, primary school students, and adolescents. Topics briefly addressed in part I, on the thought processes/capabilities of babies, concern sensorimotor thought without abstraction, the importance of physical exploration, the development of…