Nonlinear Dynamics Psychology and Life Sciences最新文献

To shed light on findings suggesting that not all job crafting strategies are (equally) favourable for employee motivation, we applied cusp catastrophe models to explore the possibility that combinations of job crafting strategies might be associated with nonlinear changes in work engagement (i.e., vigour, dedication, and absorption). We used cross-sectional data from a heterogeneous sample of 193 Greek employees and investigated increasing social and structural job resources as asymmetry factors, and increasingly challenging job demands and decreasingly hindering job demands as bifurcation factors in relation to work engagement. Cusp models, analysed with the maximum likelihood and least squares methods, proved superior to their linear alter-natives. Increasing social job resources functioned as the asymmetry factor for vigour and dedication. Increasing structural job resources was the asymmetry factor for absorption. The bifurcation factors were decreasing hindering job demands for vigour and increasing job challenges for dedication and absorption. This evidence suggests that threshold values exist in decreasing hindering and increasing challenging job demands, beyond which sudden changes in work engagement occur. The supported nonlinear models add in explaining when job crafting strategies are unfavourable for employees and have epistemological implications by suggesting that the underlying processes may be viewed as a complex dynamical system.

Stimulus-response compatibility effects illustrate the mutual depen-dence of perception and action processes. Ellis and Tucker (2000) showed that object identification was facilitated when the response required a grip that was compatible with the stimulus. In the current study, we extend grip-compatibility effects to perception of the Necker cube. Participants reported the perceived orientation of a Necker cube by orienting a hand-held cube into a compatible or an incompatible position. Participants in the incompatible condition were quickly attracted to the FRB (front-side right bottom) percept, consistent with previous work. However, participants in the compatible condition showed an extended period of metastability, switching between the two perceptual states about equally. A second experiment replicated these results and showed that a control condition in which responses were made with a key press produced intermediate levels of metastability. These results are interpreted in terms of the dynamics of bistable perception.

In this empirical research, using a database of 41,107 directors from 38 European countries from 1999 to 2015, we analyze the topological features of the director's networks and observe that the degree distribution for both men and women follows a power law. The exponent of the power law is higher for women than the one for men, suggesting a milder role of interlocking for women that points to the absence of the 'Golden Skirts' phenomenon at the European level (i.e., women who accumulate more directorships than men). This gender gap in power laws has faded away during the studied period, coinciding with two counteracting external forces. On one hand, the diffusion of corporate governance good practices in European companies, reducing the size of boards and discouraging the multiple directorships by a single person, democratizing the director's network. On the other, the political and regulatory pressure for more women on boards across Europe, creating a high demand for women in the network.

In this paper, we take one of the most emblematic models of the economic orthodoxy, the representative agent optimal growth problem, and discuss the adaptations it needs to go through to be reflective of a virtual world of interacting agents. The rational agent that maximizes intertemporal utility is replaced by a profusion of heterogeneous households, who are endowed with distinct productivity and confidence levels, who interact locally, and who make consumption-savings decisions based on a boundedly rational rule (a heuristic). We show that the three highlighted features (heterogeneity, local interaction, and non-optimality) are intertwined, and that the transformation of the standard optimal growth problem into a complexity framework requires their simultaneous consideration. Heterogeneous productivity levels trigger different technology absorption capabilities and, as a consequence, a slow process of innovation diffusion; the consumption heuristic introduces flexibility into consumption-savings choices, allowing for the coexistence of those who save with those who consume their entire current income; random contact across a population of agents makes sentiments of optimism or pessimism to spread in unpredictable ways. These processes tend to reinforce one another, provoking a change of scenery, with the conventional equilibrium growth model giving place to a multi-agent decentralized interaction platform where emergent results, rather than mechanic outcomes, are the norm. Ultimately, the new theoretical framework preserves the fundamental concept of what an economic growth model should be, at the same time it offers a richer structure of analysis, allowing for a deeper debate on the dynamics of the aggregate economy.

Many real-world tasks require people to forecast chaotic events in order to take adaptive action. This ability is considered rare, and less understood than other cognitive processes. The present study examined how the performance dynamics in a chaotic forecasting task would be affected by stressors such as cognitive workload and fatigue using two cusp catastrophe models. Participants were 147 undergraduates who were shown graphs and brief chaotic number series for which they needed to forecast the next four values. Performance data were complemented by variables known to represent cognitive elasticity versus rigidity, compensatory abilities for fatigue, and NASA TLX ratings of subjective workload. R2 for the workload cusp was .56, which compared favorably to the next best linear alternative model (.12); it contained six bifurcation variables and three measures of workload (asymmetry). R2 for the fatigue cusp was .54, which also compared favorably to the next best linear alternative (.07); it contained one bifurcation variable and two compensatory abilities. The role of field independence as an elasticity variable in the workload model and as a compensatory ability in fatigue was particularly noteworthy. Several elasticity-rigidity variables have now been identified over a series of studies. They appear to be operating in unison to produce a bifurcation effect, and different variables become salient depending on the task. Future research should consider how the ability to forecast chaos and its susceptibility to workload and fatigue carry over to dynamical decisions made while managing a complex system. Key Words.

Reading is an emerging process from human brain activity. This process sometimes is subject to disorders which has been studied from the performance of studies that provide data that are treated with qualitative and quantitative linear tools to obtain the average behavior determined and the causality of it. This research focuses on the nonlinear quantitative study of reading disorder and in this way fractal geometry and roughness interface growth theory approach were selected to be used in the processing of brain wave quantification (EEG). From the EEG of children with and without reading disorders in the State of Mexico (experimental and control group) were built time series of standard deviation for each of the 19 channels distributed in cerebral cortex. The self-affinity of these time series (treated as interfaces in motion) is studied by the scaling behavior of their structure functions. It was found that the behavior of the time series of children with reading problems (experimental group) and without them (control group) is similar to the Family-Vicsek scaling dynamic for a kinetic roughening of moving interface.

Psychologists have had a long-standing interest in the connections between group processes and team performance. The biopsychosocial perspective has piqued an interest in the connection between team processes and performance and coordinated and synchronized physiological arousal levels among team members. Studies of synchronization in work teams have been stalled by the lack of a metric that captures the total synchronization within teams of three or more people. This study examined how synchronized physiological arousal does in fact connect to team performance and related group process outcomes by utilizing the SE coefficient developed by Guastello and Peressini. Forty-three groups of 3 to 8 participants (total N = 197) participated in a survival simulation. Synchroniza-tion coefficients were produced for three task segments: watching an orientation video together, an individual decision task, and a group decision task. Primary results showed: (a) Synchronization was greater in larger groups across the three task segments. (b) A combination of the three synchronization coefficients - higher during the team task and lower otherwise - was correlated with higher workload ratings for performance demands, greater team dissatisfaction, and lower demands for time-sharing between the individual and the team.

We consider a standard macroeconomic model of a small open economy in which the flow of capital on the international foreign exchange market crucially depends on the expected exchange rate. These expectations about the exchange rate are modelled to be either homogeneous or heterogeneous, i.e., all agents may form naive expectations, or they may switch between different simple linear extrapolative or regressive predictors with respect to changing market circumstances. Using a mixture of analytical and numerical tools, we attempt to describe the characteristics of our model's dynamical systems we obtain with these different assumptions and analyse the impact of exchange rate expectations on short-term business cycle fluctuations. Our results suggest that fluctuations in both national income and the exchange rate are crucially driven by speculators' expectations. With respect to these expectations, our numerical results additionally show an ambiguous effect of extrapolative expectations on stability. Due to coexisting attractors, an increase in the strength of extrapolative expectations may have both a destabilising and a stabilising impact on dynamics. I n contrast, regressive expectations have a stabilising effect on the business cycle.

This year's cover artists are members of a newly formed team of designers and scientists known as the Science and Design Laboratory, along with flooring manufacturing experts from the Mohawk Group. This unique collab-oration creates patterns for installation on the floors of versatile commercial, public and private spaces including airports, hospitals, offices and homes. Their goal is to create human-centered designs based on psychology experiments that investigate the positive impacts of viewing fractal patterns. These include reduced physiological stress levels, enhanced cognitive skills, and heightened concentration. Here, the fractal construction process and the resulting fractal characteristics of these designs are explained.

An inverted U-shaped pattern in heart rate (HR) and a U-shaped pattern in heart rate variability (HRV) are easily recognizable when individuals experience any acute stressor. How cardiac complexity (scaling and entropy) changes under acute stress is not well known. Psychologically, emotion regulation (ER) style is likely to influence the individual's specific behavioral response when affronting stress. This study tested whether adolescents with distinct ER styles would show different patterns of linear and nonlinear cardiac changes under stressful conditions. We predicted less autonomic flexibility for adolescents with a highly negative emotional regulation (HNER) style (n = 10) than for those adolescents with a highly positive emotional regulation (HPER) style (n=10). Further, associations between linear and nonlinear measures during each condition were examined for each group. Repeated measures ANOVAs revealed that HR and HRV changed according to the predicted pattern. Higuchi's fractal dimension and Sample Entropy followed a U-shaped pattern, whereas the short-term scaling exponent followed the reverse pattern. Cardiac changes across conditions were larger in the HPER group. Significant associations between linear and nonlinear measures were found in the HPER group but not in the HNER group. Results are cautiously discussed within a multiscale framework of fluctuations of the different cardiac features.