Index for Volume 23

In this study, changes in movement coordination caused by fatigue that developed during repetitive lifting were examined. Five men performed 6 times a 5-min bout of lifting an 8-kg barbell at 15 lifts/min, using two lifting techniques; one minimized trunk rotation (squat lift), and the other minimized rotation in the knee joint (stoop lift). Kinematics and dynamics were studied by means of movement analysis and inverse dynamics, using a two-dimensional linked segment model. Within-subject variation over repetitive lifts of the time course of joint angles was smaller than between-subjects variation on the first analyzed lift. Relative timing between joint rotations did not change significantly across repetitive lifts, except between knee and hip in the squat lift. No change of the lumbosacral torque over repetitive lifts was found. The adaptability of the neural control appeared to be sufficient to accommodate the strong changes of the input-output characteristics of the muscles caused by fatigue so that an essentially constant performance of the movement act was maintained.     

To Pass or Not to Pass: A Mathematical Model for Competitive Interactions in Rugby Union

ABSTRACT. Predicting behavior has been a main challenge in human movement science. An important step within the theory of coordination dynamics is to find out the rules that govern human behavior by defining order parameters and control parameters that support mathematical models to predict the behavior of a system. Models to describe human coordination have been focused on interlimb coordination and on interpersonal coordination in affiliative tasks but not on competitive tasks. This article aims to present a formal model with two attractors to describe the interactive behavior on a 2v1 system in rugby union. Interpersonal distance and relative velocity critical values were empirically identified and were included as task constraints that define the attractor landscape. It is shown that using relative velocity as a control parameter the model offers reasonable prediction concerning the decision-making process. The model has the plasticity to adapt to other settings where interpersonal distances and relative velocities amongst system components act as significant task constraints.     

Fitts’ Theorem in Oculomotor Control: Dissociable Movement Times for Amplitude and Width Manipulations

The authors examined whether movement times (MT) for discrete saccades are constant given equivalent index of difficulty (ID) values (i.e., unitary nature of Fitts’ theorem). To that end, we contrasted ID/MT relations for saccades equated for ID but differing with respect to their target amplitudes and widths. Results showed that MT increased with increasing ID within amplitude and width conditions; however, the ID/MT slope was markedly steeper in the former condition. Thus, the amplitude condition imposed greater information processing demands than the width condition—a result indicating that the constituent elements of Fitts’ theorem are dissociable (i.e., nonunitary). Further, examination of saccade kinematics demonstrated that the optimal MT for a given target amplitude was largely independent of target width.     

Attentional and behavioural responses of spider fearfuls to virtual spiders

This study employed an immersed virtual environment (IVE) in the Nijmegen RIVERlab to study spider fearfuls’ attentional and motor reactions to virtual spiders. The participants were exposed to virtual spiders while completing an unrelated task, walking freely through a virtual museum. Compared to non-fearful controls, spider fearfuls showed an increase in state anxiety, they spent more time looking at spiders, and they exhibited spontaneous behavioural avoidance of spiders and visually similar objects. The results extend, and to some degree contradict, those of earlier studies with static pictures, and they speak to the usefulness of state-of-the-art IVEs in fundamental anxiety research.     

Relationships Between Leader-Contingent and Non-contingent Reward and Punishment Behaviors and Subordinates’ Perceptions of Justice and Satisfaction, and Evaluation of the Moderating Influence of Trust Propensity, Pay Level, and Role Ambiguity

Purpose

This research evaluates how reward and punishment behaviors are related to employee satisfaction, and how perceptions of justice mediate the effects of these behaviors. This study also seeks to examine the connection between some boundary conditions and the efficacy of reward and punishment behaviors.

Design/Methodology/Approach

Data were collected using questionnaires, and hypotheses were tested using a sample of 3,065 managers from 41 business units.

Findings

We found that contingent financial and social rewards were positively related to fairness and satisfaction, whereas punishment behaviors exert a negative influence. Findings reveal that high-trust propensity and low-pay level strengthen the positive influence of rewards on distributive justice, whereas high role ambiguity increases the positive effect of reward behaviors and the negative influence of non-contingent punishment (NCP) on superior satisfaction.

Implications

This study provided evidence that using contingent rewards is more effective in promoting positive attitudes at work than using contingent punishments. Our findings add to the evidence that organizations would benefit from encouraging their managers to use financial and social rewards and reducing the administration of NCP among performing employees.

Originality/Value

This study represents a first attempt to examine an integrated model of the effects of reward and punishment behaviors. It also contributes to this field by empirically evaluating the impact of individual and situational boundary conditions in the efficacy of these leader behaviors.     

First face hatred

The book of Joshua is the most violent book in the Bible. And it is different from all of the other books in that it has no poetry in it. And that is the lesson do not make poetry out of violence, out of bloodshed Elie Wiesel, The Anatomy of Hatred     

Emotion processing and regulation in women with morbid obesity who apply for bariatric surgery

Emotional eating, the tendency to eat when experiencing negative affect, is prevalent in morbid obesity and may indicate that ways to deal with emotions are disturbed. Our aim was to compare emotion processing and regulation between 102 women with morbid obesity who apply for bariatric surgery and 102 women from the general population (control group) and to examine in the group with morbid obesity the association of emotion processing and regulation with emotional eating. The group with morbid obesity reported higher scores on difficulty identifying feelings (alexithymia, p?=?0.002) and suppression of emotions (p?=?0.003) than the control group. In the women with morbid obesity, more negative affect and a higher difficulty identifying feelings were correlated with more emotional eating (r?=?0.36 and r?=?0.35, p?<?0.001). Our study suggests that negative emotions and unhealthy emotion processing may play a role in emotional eating, and it indicates the possible relevance of emotion processing and emotional regulation as initiating or perpetuating mechanisms in morbid obesity.     

Validating Measures of Psychological Well-being by Contrasting Samples Employed in Hazardous and Less Hazardous Work

The study investigated whether differences between contrasting groups reflect significant differences in psychological well-being scores. Membership of hazardous vs. less hazardous occupations in the same profession served as proxy measures of well-being. Antonovsky's Sense of Coherence (SOC), Block & Kremen's Ego-resiliency, and Goldberg's Emotional Stability scales were validated. Study 1 compared mine rescue team members and ordinary miners (n = 34, 41) and Study 2 police special task force members and regular officers (n = 43, 41). In Study 1, SOC and job satisfaction predicted group membership. In Study 2, satisfaction with life and extraversion scales predicted group membership, as did SOC in a secondary analysis. The SOC scale could predict psychological well-being in hazardous work settings.