Studied the influence of school- and age-related variables on tasks involving quantitative skills. On conservation of number, performance improved as a function of age but not schooling. On mental arithmetic, accuracy improved with schooling rather than age. Results support the utility of the cut-off design for investigating instructional and…

In order to evaluate possibilities of fitting myoelectrically controlled prosthetic arms on infants, this study examined whether 32 infants (1-6 months) could learn to control environmental contingencies by means of contracting the forearm flexor muscle group. Results indicated that older subjects (age greater than 104 days) demonstrated learning,…

Tested the ability of 19 older adults, given additional training in a mental imagination technique, to approach the performance of 16 younger adults on serial word recall tasks. Results indicated that negative age differences in older adults' performance were substantial, resistant to extensive practice, and applicable to all subjects. (BC)

Studied the possibility that children's decisions regarding naughtiness and types of punishment differ according to age and sex. Subjects were interviewed after hearing two stories from Piaget's study of children's moral reasoning. Significant age variability was found. Findings imply that children did not make the connection between the act and…

Examined development of concept of suicide in 60 children. Found that 10 percent of first, 50 percent of third, and 95 percent of fifth graders had basic understanding of suicide. Attitudes toward suicide were neutral or negative. Concept of suicide was significantly related to concept of death and experiences with death and was also related to…

A study compared child and adult dyslexic readers to normal readers. Results indicated that dyslexics do not acquire appropriate levels of phoneme awareness, regardless of their age or reading levels. However, their awareness of onsets and rimes developed as their reading skills developed. (BG)

Explored whether there are changes with age in understanding the specific distinction between natural and human-made phenomena and whether an appreciation of this distinction influences children's beliefs about the possibility of altering or transforming different categories of objects. Found that this distinction, a powerful organizer for adults,…

In this study of sensitivity to viewpoint, children between the ages of 6 and 14 years were asked to draw an L-shaped array of 3 cubes from 1 of 3 views. At every age, children showed sensitivity to their view in the sense that there were consistent differences between the drawings produced in the three viewing conditions. (SH)

Examined third and seventh graders during dual tasks to estimate the mental effort required to elaborate accessible noun pairs. Findings indicated that the accessibility difference was limited to the third grade. Findings support a knowledge-base view of developmental differences in elaboration effort. (SH)

Assessed the cognitive readiness for parenting of 171 pregnant adolescents, 48 nonpregnant adolescents, and 38 pregnant adults. Found that adolescents were less cognitively prepared, experienced more stress in parenting, and were less adaptive in their parenting style than adult mothers. Relationships between cognitive readiness and parenting…

Children and adults listened to stories that contained a goal sentence and an inconsistent outcome. Several encoding and retrieval factors were simultaneously manipulated in the stories. Interaction effects in situations with weak encoding constraint decreased with age. (BC)

Tested children's ability to produce appropriate similes, evaluate a given simile's appropriateness, and select an appropriate simile. Minimum competence appeared around the age of three years for the multiple choice task, four years for the production task, and five to seven years for the evaluation task. (BC)

Two studies investigated 4- to 7-year-olds' understanding that trait can be causal mechanisms based on desires or mere summaries of behavioral regularities. Results suggested that children change from viewing traits as behavioral regularities to understanding them as internal mediators and that advances in understanding desire underlie this…

Established the differential maturation of rapid-speaking durations and the durations of interword pauses in the memory-span-task responses of first, third and fifth graders. Found that a particular memory span is accompanied by different profiles of processing rates in children of different ages. (Author)

Twenty-nine children with learning disabilities (LD) in grades 2 and 4 through 7 were compared with children without LD for their development of proportional structures of thought. Significantly fewer children with LD had constructed second-order logical structures necessary to act on problems using multiplicative and preproportional reasoning.…