Two aspects of the cognitive development of a 14- to 18-month-old blind child are reported: the development of procedures for the intentional control of objects and the development of certain classificatory skills. (Author)

Eighteen-month-old children performed sorting tasks and their parents completed checklists of words used by the children. Children who performed exhaustive grouping, or grouping of objects of different kinds in different locations, were reported as using more words than children who did not perform exhaustive grouping. (BC)

In three shape-constancy experiments, 4- and 7-year olds viewed a circular disc oriented at a slant. All subjects exaggerated circularity of the disc when they knew the object was a circle. Findings suggest that knowledge of reality contaminates judgments of appearance in circle task and this is the same bias that features in realist errors in…

The emerging ability to represent an oscillating moving object over occlusions was studied in 7-21-week-old infants. The object moved at 0.25 Hz and was either occluded at the center of the trajectory (for 0.3 s) or at one turning point (for 0.7 s). Each trial lasted for 20 s. Both eye and head movements were measured. By using two kinds of…

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…

This study tested Piaget's explanation of infants' perseverative error in manual search by comparing searches when the object was (1) hidden, (2) covered but visible, and (3) uncovered. Errors occurred under all three conditions, with conflict at a maximum when the object was hidden. (Author/JMB)

Statistical analysis of many studies on Piaget's stage 4 object concept attempts to synthesize available quantitative data. Factors of this "meta-analysis" include: (1) effects of age; (2) number of A trials; (3) length of delay between hiding and search; (4) number of locations; and (5) visual properties of hiding arrays. Includes…

Investigates the degree to which object familiarity and motivational factors influence infants' search behavior in an object-permanence test. (Author/MP)

This study examined two alternative interpretations of violation-of-expectation findings that young infants can represent hidden objects. Findings indicated that 5-month-olds succeeded in reasoning about the interaction of a visible and a hidden object even though the 2 objects were never simultaneously visible and a 3- or 4-minute delay preceded…

Recent research on infants' responses to occlusion and containment events indicates that, although some violations of the continuity principle are detected at an early age e.g. Aguiar, A., & Baillargeon, R. (1999). 2.5-month-old infants' reasoning about when objects should and should not be occluded. Cognitive Psychology 39, 116-157; Hespos, S.…

The use of gaze shifts as social cues has various evolutionary advantages. To investigate the developmental processes of this ability, we conducted an object-choice task by using longitudinal methods with infant chimpanzees tested from 8 months old until 3 years old. The experimenter used one of six gestures towards a cup concealing food; tapping,…

Tested two competing hypotheses explaining infants' failure to search for an object in a new hiding place: (1) that the concept of object is not yet differentiated from the concept of place, and (2) that difficulties in spatial localization are responsible for the search failure. (Author/JMB)

Infants aged 3-5 months (mean of approximately 4 months) were given a novel anticipatory looking task to test object permanence understanding. They were trained to expect an experimenter to retrieve an object from behind a transparent screen upon hearing a cue (''Doors up, here comes the hand''). The experimenter then hid the object behind one of…

In the present research, 6-month-old infants consistently searched for a tall toy behind a tall as opposed to a short occluder. However, when the same toy was hidden inside a tall or a short container, only older, 7.5-month-old infants searched for the tall toy inside the tall container. These and control results (1) confirm previous…

Two experiments explored the existence and the development of relations between action representations and object representations. A priming paradigm was used in which participants viewed an action pantomime followed by the picture of a tool, the tool being either associated or unassociated with the preceding action. Overall, we observed that the…