When older siblings were present with infants and their mothers in the backyard of a private home, the infants went further from their mothers, traversed a larger area of the yard, left their mothers more quickly, and stayed away longer. (RH)

Two experiments used object-manipulation tasks to examine whether one- to two-year-olds form superordinate-like categories by attending to object parts. Findings indicated that 14- and 18-month-olds behaved systematically toward categories with different, but not matching, parts. Without part differences, none formed superordinate categories.…

The purpose of this study was to longitudinally examine the development of symbolic play in 2-year-old Japanese infants. The subjects were four children who were individually tested once a month from the age of 12 to 24 months in laboratory settings. Assessment materials consisted of three sets of miniature toys, a doll and junk objects. Each set…

Examines the issue of object sorting in early infancy. Forty-eight infants at 6, 9, and 12 months were presented with eight sets of small, manipulable objects. At six months, selective manipulation was absent; at nine months, 94 percent of the infants sequentially touched similar objects and at 12 months 100 percent did so. (Author/DB)

Evaluated 9-, 14-, and 19-month olds' strategies as they grasped and used spoons presented with the handle alternately oriented to left or right. Found that younger children reached with their preferred hand, disregarding the item's orientation. Older children anticipated the problem, alternated the hand used, and achieved an efficient radial grip…

Examined infants' ability to retrieve an object from atop a slightly larger object. Found that even 5-month-olds could retrieve objects close in size and fully contiguous with their bases when demands on reaching skill were reduced. Proposed that when they fail this task, it is because they lack the skill to reach the top object without…

THE PURPOSE OF THIS STUDY WAS TO FIND OUT WHETHER SOCIAL CLASS DIFFERENCES IN INTELLECTUAL DEVELOPMENT ARE PRESENT IF (1) CHILDREN FROM SOCIALLY DISORGANIZED SLUM FAMILIES ARE COMPARED WITH CHILDREN FROM STABLE, LOW INCOME AND MIDDLE INCOME FAMILIES, (2) THE PIAGET OBJECT SCALE, A NEW MEASURE OF COGNITIVE DEVELOPMENT BASED ON PIAGET'S SENSORIMOTOR…

Studied the early development of exploratory behavior in 99 infants of 2-5 months. Results show that there are significant changes in spontaneous multimodal exploration of a novel object between 2 and 5 months. (RJC)

Six- and nine-month-old infants were exposed to contingent or non-contingent perceptual stimulation from a source which was spatially displaced at 60 from the infant's midline. Reliable operant acquisition was observed in the case of the nine-month-old infants, but not in the case of the six-month-old infants whose performance was similar to that…

A MAIN PROBLEM ARISING IN THE STUDY OF CATEGORIZING BEHAVIOR IN PRESCHOOL CHILDREN BY MEANS OF SORTING PROCEDURES WAS THAT PERFORMANCE APPEARED TO BE VERY MUCH A FUNCTION OF THE CHILD'S COMPREHENSION OF THE PARTICULAR VERBAL INSTRUCTIONS EMPLOYED BY THE EXPERIMENTER IN PRESENTING THE TASK. THE SPECIFIC AIMS OF THE FIRST STUDY WERE TO INVESTIGATE…

Reports a series of studies conducted to investigate possible differences in the exploratory manipulation and play behavior of human infants 7-1/2- 11-1/2 months of age as a function of the attributes of the stimulus, the familiarity of the subject with the stimuli, the age and sex of the infants, and individual differences. (Author/CS)

Synergistic psychology has been proposed as a meta theory for synthesizing different psychological theories into an explanation of how social, cognitive, and biological factors interact in human behavior. The basic theoretical assumption in synergistic psychology is that internalized social interactions become higher mental functions that regulate…