For many decades, tool use has been viewed primarily as a cognitive achievement, an ability that separates not only adults and older children from infants, but humans from virtually all other species. According to this standard account, tool use and associated means-ends behaviors are dependent on symbolic or representational thinking. Organisms…

Investigates the predictability of cognitive differences at 12 months from infant and maternal behaviors at 4 months. Overall, the results show that some individual differences in cognition may be predictable across the first year of life. (Author/RH)

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)