Is the learning of goal-directed displacement effector-independent?

The present experiment was designed to investigate whether the learning of goal-directed locomotion is effector independent. To answer this question a bilateral transfer of learning paradigm was used. We wanted to find out whether learning can be transferred from a trained effector system to an untrained one. Sixteen participants were asked to proceed through virtual hallways, while walking on a treadmill or handling of a joystick, in order to cross a pair of oscillating doors. Participants received 1050 training trials on the specific effector system before being transferred to the untrained one. Results indicated a clear transfer from handling to walking and only a moderate transfer from walking to handling. This asymmetrical transfer provides partial support in favor of the effector independent hypothesis. Both the theoretical implications of this work and the possible mediating effect of calibration are discussed.     

Testosterone and child and adolescent adjustment: the moderating role of parent-child relationships

In a sample of established middle- and working-class families with normally developing children and adolescents ranging in age from 6 to 18 years, sons' and daughters' testosterone levels showed little direct connection to risk behavior or symptoms of depression. In contrast, testosterone's positive relation with risk behavior and negative relation with depression were conditional on the quality of parent-child relations. As parent-child relationship quality increased, testosterone-related adjustment problems were less evident. When relationship quality decreased, testosterone-linked risk-taking behavior and symptoms of depression were more in evidence. Few relations were found between parents' testosterone and child behavior. Boys' and girls' ages and stages of pubertal development were important for understanding the expression of hormone-related problem behavior in some cases but not in others.     

Creating an organizational awareness of ethical responsibility about information technology

In a time of rapid technological and social change, business organizations must help their employees develop a new appreciation of how social and ethical values are being shaped and challenged by evolving information technologies. Many ethical and social conflicts have arisen around the advanced information technology used today. The emerging technologies continue to create situations not previously encountered. There are numerous risks facing corporations involved in the use of computing technology. Leaders of organizations looking ahead to assess the impact of technological changes can try to prepare their employees for the future. This paper addresses the urgent need for individuals in corporations to become more knowledgeable about computing technologies and their impact.     

Spatial and temporal adaptations that accompany increasing catching performance during learning

The authors studied changes in performance and kinematics during the acquisition of a 1-handed catch. Participants were 8 women who took an intensive 2-week training program during which they evolved from poor catchers to subexpert catchers. An increased temporal consistency, shift in spatial location of ball-hand contact away from the body, and higher peak velocity of the transport of the hand toward the ball accompanied their improvement in catching performance. Moreover, novice catchers first adjusted spatial characteristics of the catch to the task constraints and fine-tuned temporal features only later during learning. A principal components analysis on a large set of kinematic variables indicated that a successful catch depends on (a) forward displacement of the hand and (b) the dynamics of the hand closure, thereby providing a kinematic underpinning for the traditional transport-manipulation dissociation in the grasping and catching literature.     

The Theory of Planned Behavior: Some Measurement Issues Concerning Belief-Based Variables

The theory of planned behavior presents clear operational definitions of attitudes, subjective norm, perceived behavioral control, and each of their corresponding belief-based measures. Theoretically, the direct and indirect measures of a given construct must be closely correlated. Empirical results, however, indicate that this is not always the case. In the present study, 2 of the factors that could be responsible for this situation-namely, the scaling of the variables defining each belief-based construct and the adequacy of using an expectancy-value model within the belief-based measures-were verified among a data set of 16 studies concerned with the application of the theory of planned behavior to the field of health. The results indicate that the scaling method used affected the correlation coefficients between indirect and direct measures. However, the face validity of these scaling methods must be demonstrated. The results also support the idea that, in most cases, using the expectancy-value model is no better than using only one arm of the belief-based measure.