Induced mood change and dysfunctional attitudes in remitted bipolar I affective disorder

This study investigated the possibility that, in remitted bipolar I affective disorder, dysfunctional attitudes are mood-state dependent. Participants were 120 individuals with remitted bipolar I disorder, remitted unipolar depression, or no history of affective disorder. The Dysfunctional Attitudes Scale (DAS; Weissman, 1979) was completed before and after positive or negative mood challenge. Following mood increase, the bipolar group changed significantly less in DAS total score than did the other 2 groups, and in goal-striving and achievement attitudes relative to the unipolar group. These findings did not provide clear support for the mood-state dependency theory in bipolar disorder, arguing instead for the presence in bipolar I disorder of dysfunctional cognitions that show characteristic resilience in the face of minor positive mood increase.     

Relations of perceived physical self-efficacy and motivational responses toward physical activity by urban high school students

To be effective in promoting physical activity among urban, minority adolescents, the factors and psychological processes that motivate them to engage in and maintain a physically active lifestyle should be examined. The relation of physical self-efficacy and motivational responses toward physical activity in 46 urban minority adolescents was explored. As hypothesized, there were significant positive relationships among Percieved Physical Ability, Physical Self-presentation Confidence, Effort, and Enjoyment (coefficients ranged from .29 to .80), suggesting that participants who had higher perceived physical ability were likely to report higher perceptions of self-presentation, more enjoyment of physical activity, and harder work in physical activity. These results indicate specific relationships among Effort, Enjoyment, Perceived Physical Ability, and Physical Self-presentation Confidence in this sample. Physical self-efficacy appears to be a stronger predictor of motivational responses in physical activity. Practical implications for physical educators include incorporating strategies known to develop self-efficacy, such as mastery experiences involving successive trials of increasing difficulty, self-observation, external feedback, peer modeling, and verbal persuasion.     

Inhibition of return to an occluded object depends on expectation

Inhibition of return (IOR) is indexed by slower reaction times to targets presented at previously attended locations or objects. If a moving object is occluded, some studies find IOR, others do not. Four experiments examined whether this inconsistency hinges on the observer's expectation as to whether the object continues to exist at the end of its motion sequence. Results showed that observer expectation is a powerful determining factor: IOR occurs only if the observer expects the object to continue to exist. In contrast, if the object is not occluded, IOR occurs only if the object remains on view immediately before the target is presented. It was concluded that 2 factors, object continuity and observer expectation, mediate both location- and object-based IOR.     

The moderating effects of employee tenure on the relation between organizational commitment and job performance: a meta-analysis

This meta-analysis investigated the correlation between attitudinal commitment and job performance for 3,630 employees obtained from 27 independent studies across various levels of employee tenure. Controlling for employee age and other nuisance variables, the authors found that tenure had a very strong nonlinear moderating effect on the commitment-performance correlation, with correlations tending to decrease exponentially with increasing tenure. These findings do not appear to be the result of differences across studies in terms of the type of performance measure (supervisory vs. self), type of tenure (job vs. organizational), or commitment measure (Organizational Commitment Questionnaire [L. W. Porter, R. M. Steers, R. T. Mowday, & P. V. Boulian, 19741 vs. other). The implications and future research directions of these results are discussed.     

Mechanisms of same/different abstract-concept learning by rhesus monkeys (Macaca mulatta)

Experiments with 9 rhesus monkeys (Macaca mulatta) showed, for the first time, that abstract-concept learning varied with the training stimulus set size. In a same/different task, monkeys required to touch a top picture before choosing a bottom picture (same) or white rectangle (different) learned rapidly. Monkeys not required to touch the top picture or presented with the top picture for a fixed time learned slowly or not at all. No abstract-concept learning occurred after 8-item training but progressively improved with larger set sizes and was complete following 128-item training. A control monkey with a constant 8-item set ruled out repeated training and testing. Contrary to the unique-species account, it is argued that different species have quantitative, not qualitative, differences in abstract-concept learning.     

Interplay of biomechanical constraints and kinematic strategies in selecting arm postures

In this study, the authors examined the interplay between biomechanics and control strategies in the resolution of excess degrees of freedom at the joint level. Seven participants made aimed arm movements from 30 starting points and several starting postures to targets. Final arm postures for movements to a target exhibited substantial joint angle variation. Through regression modeling and by comparing observed final arm postures with biomechanically plausible postures, the authors identified 3 kinematic strategies: (a) Maintain deviations from the average angle at the starting point to the joint's final posture; (b) make torso rotations that are a fixed proportion of shoulder rotations; and (c) adopt a characteristic combination of 4 wrist-positioning approaches. The results demonstrated that kinematic strategies can account for substantial variance in final arm postures, if one takes into account 2 types of individual differences-those that arise inevitably from biomechanical constraints and those that reflect choices in movement strategy.     

Planning and executing simple movements: contributions of relative-time and overall-duration specification

In 3 experiments, the authors used a precuing protocol to examine the nature and cost of programming and the subsequent reprogramming of a movement's relative time and overall duration. Initial programming followed a fixed-order specification; knowledge of the necessary relative time was required before information regarding overall duration could be used in a manner that expedited response planning. In the case of reprogramming, however, when a modification had to be made in either the relative time or overall duration of the anticipated and already-prepared response, performers chose to completely reprogram the entire response. Complete reprogramming occurred even when the performer had correctly prepared the higher order relative-time component and only had to modify the overall duration of the movement. The data indicate that organizing movement timing before movement initiation is accomplished in a fundamentally different manner depending on whether the movement is being initially compiled or modified.     

A functional MRI study of human amygdala responses to facial expressions of fear versus anger

Functional magnetic resonance imaging (fMRI) of the human brain was used to compare changes in amygdala activity associated with viewing facial expressions of fear and anger. Pictures of human faces bearing expressions of fear or anger, as well as faces with neutral expressions, were presented to 8 healthy participants. The blood oxygen-level dependent (BOLD) fMRI signal within the dorsal amygdala was significantly greater to Fear versus Anger, in a direct contrast. Significant BOLD signal changes in the ventral amygdala were observed in contrasts of Fear versus Neutral expressions and, in a more spatially circumscribed region, to Anger versus Neutral expressions. Thus, activity in the amygdala is greater to fearful facial expressions when contrasted with either neutral or angry faces. Furthermore, directly contrasting fear with angry faces highlighted involvement of the dorsal amygdaloid region.