Investigated the possibility that previous reports of a relation between locomotor status and stage-4 object permanence performance could be generalized to performance on an object localization task. Findings suggest that the effects of locomotor experience on infants' search performance are quite specific and mediated by a variety of factors that…

If after teaching a label for 1 object, a speaker does not name a nearby object, 3-year-olds tend to reject the label for the nearby object (W.E. Merriman, J.M. Marazita, L.H. Jarvis, J.A. Evey-Burkey, and M. Biggins, 1995a). In Studies 1 (5-year-olds) and 3 (3-year-olds), this effect depended on object similarity. In Study 2, when a speaker used…

A hypothesized developmental sequence of agent use in pretending was tested in 36 infants between 14 and 24 months of age and was compared with the development of object permanence. (JMB)

Changes in children's categorization behavior between 15 and 21 months of age and the relation of these changes to developments in language, object permanence, and means-end understanding are reported. (PCB)

Purpose of the study was to determine whether a name for a toy affects an infant's attentional preference for a toy and whether this process is related to the infant's concept of subject permanence. (Authors)

Examined the role of perceptual-motor development in a typical Stage IV task. The performance of ten infants was compared on a Stage IV object permanence task when a cloth cover was used and when a small card cover was used. (JMB)

Eight- to 12-month-olds might make A-not-B errors, knowing the object is in B but searching at A because of ancillary (attention, inhibitory, or motor memory) deficits, or they might genuinely believe the object is in A (conceptual deficit). This study examined how diligently infants searched for a hidden object they never found. An object was…

Reports two experiments which were designed to establish whether errors in infants' manual searches for objects are caused by changes in the location of an object or by the change in the relation between old and new hiding places. (JMB)

Two studies tested whether 12- and 24-month olds' self-knowledge differed from their knowledge of others (mother or inanimate object), or whether toddlers' knowledge of persons (self and mother) differed from knowledge of objects. Results showed that 12-month olds were more sensitive than older toddlers to perceptual features of objects. Data were…

How do infants come to understand references to absent objects? 14-month-old infants first learned a name for a novel toy, which was then placed out of view. The infants who listened to a story mentioning the nonvisible object, looked, pointed, and searched for it more often than did infants who heard a story using a different name. Their behavior…

The perceived spatiotemporal continuity of objects depends on the way they appear and disappear as they move in the spatial layout. This study investigated whether infants' predictive tracking of a briefly occluded object is sensitive to the manner by which the object disappears and reappears. Five-, 7-, and 9-month-old infants were shown a ball…

Recent studies on the biological development of the prefrontal cortex in rhesus monkeys are reviewed. These studies have elucidated the basic neural circuitry underlying the delayed-response function in adult nonhuman primates and suggest that a critical mass of cortical synapses is important for the emergence of this cognitive function. (BN)

Reports two experiments in which eight patients with organic memory disorders exhibited a pattern of search behavior that resembled mnemonmic precedence--the ability to retrieve an object at an initial location, but not at a new location. (HOD)

When an object moves behind an occluder and re-emerges, 4-month-old infants perceive trajectory continuity only when the occluder is narrow, raising the question of whether time or distance out of sight is the important constraining variable. One hundred and forty 4-month-olds were tested in five experiments aimed to disambiguate time and distance…