Voluntary Engagement in an Open Web-Based Encyclopedia: Wikipedians and Why They Do It

The online encyclopedia Wikipedia is a highly successful “open content” project, written and maintained completely by volunteers. Little is known, however, about the motivation of these volunteers. Results from an online survey among 106 contributors to the German Wikipedia project are presented. Both motives derived from social sciences (perceived benefits, identification with Wikipedia, etc.) as well as perceived task characteristics (autonomy, skill variety, etc.) were assessed as potential predictors of contributors' satisfaction and self-reported engagement. Satisfaction ratings were particularly determined by perceived benefits, identification with the Wikipedia community, and task characteristics. Engagement was particularly determined by high tolerance for opportunity costs and by task characteristics, the latter effect being partially mediated by intrinsic motivation. Relevant task characteristics for contributors' engagement and satisfaction were perceived autonomy, task significance, skill variety, and feedback. Models from social sciences and work psychology complemented each other by suggesting that favorable task experiences might counter perceived opportunity costs in Wikipedia contributors. Moreover, additional data reported by Wikipedia authors indicate the importance of generativity motives.     

Associations between psychological characteristics and indicators of metabolic syndrome among Chinese adults

Current knowledge about the relationship between psychological characteristics and metabolic syndrome (MetS) components is limited in Asian populations. The purpose of this study is to investigate linkages between physiological markers of MetS and life satisfaction, hostility, and depression in Chinese adults. Secondary analyses were conducted using cross-sectional data from parents of randomly selected middle school students participating in a pilot study in Qingdao, China. Among 440 parents who consented to participate (237 women, 203 men), 368 provided valid responses in all three categories of psychological characteristics, and only those subjects were included in these analyses. General linear models and logistic regressions were run separately by gender, controlling for covariates. Among women, life satisfaction was inversely associated with triglyceride levels (p = .04), LDL-C (p < .01), risk of hypertriglyceridemia (OR[.53], p < .01), HDL-C (OR[.78], p = .03), and MetS (OR[.52], p = .03). No associations were found between life satisfaction and any psychological characteristics among men. Among women, hostility was positively associated with triglyceride level (p = .04) and risk of hypertriglyceridemia (OR[2.12], p < .05). Among men, hostility was positively associated with waist circumference (p = .04), waist-hip ratio (p < .05), and fasting plasma insulin (p < .01). Depression was not associated with any physiological measurement in either gender. These findings indicate that relationships exist between certain psychological characteristics and physiological indicators of MetS among Chinese adults, although there may be important differences between genders.     

Wild capuchin monkeys anticipate the amount of ripe fruit in natural trees

Tropical forests have a high diversity of tree species which have very low densities and vary across time in their seasons of peak fruiting and maturation rates. As evidence of the ability of primates to track or anticipate changes in fruit production at individual trees, researchers have used the increased speed of primate groups toward more rewarding food patches. We analyzed the speed of approach to natural trees of wild capuchin monkeys under the effect of scramble competition, after excluding any plausible visual, olfactory and auditory cues. We conducted all-day group follows of three habituated capuchin groups at Iguazú National Park, Argentina, collecting data on ranging behavior and patterns of visits to fruit trees in relation with their location and fruit availability. Travel speed varied according to the expected reward at a feeding tree, increasing as rewards increased from low values, but decreasing again at very high values. Also, travel speed varied with time of day, decreasing from the time of first activity as the monkeys became less hungry, and increasing again toward late afternoon. Measures of unripe fruit cover did not explain variation in travel speed at any distance from a focal tree. Our data imply that, after excluding sensory cues, capuchins appear to anticipate time-varying ripe fruit quantity of natural resources, suggesting that they use memory of tree location and anticipation of fruit maturation. We also confirm that speed is a good measure about expectations of resources, as has been shown in previous studies.     

The director task: A test of Theory-of-Mind use or selective attention?

Over two decades, the director task has increasingly been employed as a test of the use of Theory of Mind in communication, first in psycholinguistics and more recently in social cognition research. A new version of this task was designed to test two independent hypotheses. First, optimal performance in the director task, as established by the standard metrics of interference, is possible by using selective attention alone, and not necessarily Theory of Mind. Second, pragmatic measures of Theory-of-Mind use can reveal that people actively represent the director’s mental states, contrary to recent claims that they only use domain-general cognitive processes to perform this task. The results of this study support both hypotheses and provide a new interactive paradigm to reliably test Theory-of-Mind use in referential communication.     

Links Between Stressful Life Events and Proactive and Reactive Functions of Aggression

Recently, more attention has been devoted to understanding how stressful life events might relate to proactive and reactive aggression. Findings suggest that stressful life events are more strongly linked to reactive, than proactive, aggression; however, it is unclear whether the impact of stressful life events on proactive and reactive aggression might vary as a function of the level of exposure to or type of stressful life event. The current study examined how level of exposure to stressful life events (i.e., witnessed, experienced, and learned about) and stressful life event types (i.e., war zone exposure, sexual victimization, interpersonal violence, and other trauma exposure) related to proactive and reactive aggression. The sample was comprised of 500 undergraduate students (M = 18.96, SD = 1.22, 49.6% male) recruited from a Midwestern university. Findings indicated that all three levels of stressful life event exposure (i.e., experienced, witnesses, and learned) were associated with reactive aggression; however, only witnessed stressful life events were associated with proactive aggression. Clinical implications and future directions are discussed.     

Influence of text cohesion on the persuasive power of expository text

The present study examined how global text cohesion affects persuasion and memory for message arguments presented in expository text. Sixty-nine participants who held a neutral prior attitude towards NATO read a persuasive text about NATO that was either high or low in global cohesion. After reading, participants voted whether Finland should seek NATO membership and filled in an attitude questionnaire. After a 1-week delay they returned for a surprise recall task. The results showed that the high cohesion text was more persuasive than the low cohesion text. Moreover, attitude after reading but not text cohesion predicted later recall of the message arguments. The results show that global text cohesion increases text's persuasive power and that readers who form a positive attitude have better memory of the persuasive arguments after a delay than readers who are less persuaded.     

Understanding social motor coordination

Recently there has been much interest in social coordination of motor movements, or as it is referred to by some researchers, joint action. This paper reviews the cognitive perspective’s common coding/mirror neuron theory of joint action, describes some of its limitations and then presents the behavioral dynamics perspective as an alternative way of understanding social motor coordination. In particular, behavioral dynamics’ ability to explain the temporal coordination of interacting individuals is detailed. Two experiments are then described that demonstrate how dynamical processes of synchronization are apparent in the coordination underlying everyday joint actions such as martial art exercises, hand-clapping games, and conversations. The import of this evidence is that emergent dynamic patterns such as synchronization are the behavioral order that any neural substrate supporting joint action (e.g., mirror systems) would have to sustain.     

Understanding the Effect of Social Capital on the Depression of Urban Chinese Adolescents: An Integrative Framework

Using data from an ongoing longitudinal study of 5,164 adolescents and their parents from seven cities in mainland China, this study investigated how social capital embedded in the family and the community, together with family human capital and financial capital, influenced the depressive symptoms of urban Chinese adolescents within an integrative framework. The structural equation modeling results suggested that higher community social capital was associated with lower level of adolescent depressive symptoms and was the strongest predictor among all these contextual factors. Family social capital played a significant role in mediating the effects of all other contextual factors on adolescent depressive symptoms. Unexpectedly, higher family financial capital predicted increased depressive symptoms both directly and indirectly through its negative effect on family social capital. As for gender, female adolescents reported more depressive symptoms as a result of less available family social capital. Implications of these findings for theory, practice, policy, and future research are discussed.     

The Simulation of Smiles (SIMS) model: Embodied simulation and the meaning of facial expression

Recent application of theories of embodied or grounded cognition to the recognition and interpretation of facial expression of emotion has led to an explosion of research in psychology and the neurosciences. However, despite the accelerating number of reported findings, it remains unclear how the many component processes of emotion and their neural mechanisms actually support embodied simulation. Equally unclear is what triggers the use of embodied simulation versus perceptual or conceptual strategies in determining meaning. The present article integrates behavioral research from social psychology with recent research in neurosciences in order to provide coherence to the extant and future research on this topic. The roles of several of the brain's reward systems, and the amygdala, somatosensory cortices, and motor centers are examined. These are then linked to behavioral and brain research on facial mimicry and eye gaze. Articulation of the mediators and moderators of facial mimicry and gaze are particularly useful in guiding interpretation of relevant findings from neurosciences. Finally, a model of the processing of the smile, the most complex of the facial expressions, is presented as a means to illustrate how to advance the application of theories of embodied cognition in the study of facial expression of emotion.