Gender influencers on work values of black adolescents

Work values and key influencers of a sample of black male and female adolescents were examined. Results indicated that boys and girls valued both the intrinsic and extrinsic rewards of work; however, girls reported slighter stronger extrinsic values than did boys. In addition, the sexes reported differences in the importance of specific work values such as "making lots of money," and "doing important things." When naming a key influencer, respondents tended to cite a same-sex and race individual. Sex of one's key influencer was related to certain work values, with subjects reporting a male key influencer valuing "trying out one's own ideas" and "having a secure future" more than those reporting a female key influencer. The interaction of sex of subject and sex of key influencer was significant on one of the work value outcomes. Implications of these findings are considered.     

Development of strategic skills in impulsive and reflective children: a longitudinal study of metacognition

This study examined the relationships between metamemory and strategic behavior in impulsive and reflective children. One hundred thirty children from the fourth, fifth, and sixth grades participated. Seventy-seven of these children had been tested 3 years earlier on metamemory and cognitive tempo tasks. At pretraining, children were assessed on metamemory, cognitive tempo, summarization skills, and teacher ratings of impulsive behavior in the classroom. Next, children in three experimental groups received prose summarization instructions, summarization instructions in conjunction with metacognitive training about the importance of a reflective approach to learning, or no instructions. Following training, children were again measured on tempo, summarization skills, and teacher ratings of impulsivity. Analyses of strategy maintenance data indicated superior performance for children who had received both summarization and metacognitive training. Causal modeling analyses showed that early metamemory was an antecedent of later strategy acquisition. The dual role of metacognition as a precursor of later strategy acquisition and controller of lower level strategies was highlighted.     

A developmental study of timing behavior in 4 1/2- and 7-year-old children

The present study investigated effects of age and instructions on temporal regulations of behavior in children. In the first experiment 4 1/2-year-old and 7-year-old subjects were trained with a DRL (differential reinforcement of low rates) 5-s and a DRL 10-s schedule. Results demonstrate that age and timing performance are related. Seven-year-olds are more efficient than the 4 1/2-year-olds. A striking decline in the 4 1/2-year-old children's capacity to space responses was observed in the DRL 10-s schedule as compared to the DRL 5-s schedule. Analysis of individual performances suggests that the evolution of DRL performance between 4 and 7 years of age depends not only on the development of the capacity to delay responding but also on the acquisition of the ability to represent the reinforcement contingencies, that is, the temporal parameters of the task to oneself. In order to test this hypothesis a second experiment was conducted where instructions to wait between operant responses were given to a group of 4 1/2-year-old subjects at the beginning of a DRL 5-s and a DRL 10-s schedule. The results show that these instructions enhance DRL performance. By directing the 4 1/2-year-old subjects' attention to the temporal requirements of the task, instructions led to efficient performance and accurate timing of responses to the DRL schedule.     

Quantitative assessment of infant reaching movements

We have identified a fundamental property of human motor behavior as a tight coupling of the curvature-speed relationship in the reaching movements of 5- to 9-month-old infants. This relationship termed a movement unit, occurs regardless of the distance of duration of the reach and in spite of the developmental change that occurs in grasping during this period. Movement unit durations are tightly clustered around 200 ms regardless of overall duration or distance or the position of the unit in the reach. The curvature-speed coupling has been identified by others in adult reaching and handwriting. Models of biological motor control must account for this invariant relationship.