Force Control of Ankle Dorsiflexors in Young Adults: Effects of Bilateral Control and Leg Dominance

Abstract

We investigated whether bilateral lower-limb control and leg dominance affect force control ability in 15 healthy young adults (9 males and 6 females, age =26.8?±?4.1 years). Participants performed isometric ankle dorsiflexion force control tasks, matching a visual target (10% of maximal effort) as quickly and precisely as possible in ballistic and tonic tasks. Performance was evaluated using force error, force steadiness, amount of muscle activity of the tibialis anterior, and response time characteristics. Results showed no significant effects of leg dominance during both ballistic and tonic tasks, while bilateral condition resulted in significantly larger error, less force steadiness, compared to unilateral condition, and only during the tonic task. Consequently, bilateral control, specifically in tasks utilizing feedback control (i.e., tonic task) might affect force control ability, possibly because of the interhemispheric inhibition to meet bilateral task complexity and integrate afferent bilateral sensory information from both right and left legs.     

Compensating for Innovation: Extreme Product Incongruity Encourages Consumers to Affirm Unrelated Consumption Schemas

New products are often extremely incongruent with expectations. The inability to make sense of these products elevates anxiety and leads to negative evaluations. Although scholars have predominantly focused on combating the negative response to extreme incongruity, we propose that extreme incongruity may have implications that extend beyond the category. We base our predictions on the concept of fluid compensation, which suggests that when people struggle to make sense of something, they will nonconsciously reinforce highly accessible schemas in unrelated domains. Four studies confirm that extreme incongruity encourages fluid compensation, such that it elevates preference for dominant brands (study 1), green consumption (studies 2 and 4), and ethnocentric products (study 3). We isolate the causal role of anxiety using moderation tasks and biometric feedback. Furthermore, we demonstrate that compensation has an immediate dampening effect on arousal intensity. Thus, if consumers can compensate before explicitly evaluating an extremely incongruent product, their evaluations tend not to be negative. Taken together, we document that extreme innovations encourage compensation, and in compensating, consumers can become more receptive to extreme innovations.     

The inheritance of social dominance rank in red grouse (Lagopus Lagopus scoticus)

Social dominance rank in red grouse has a large inherited component. The relative contributions of mothers and fathers to the dominance ranks of their sons and daughters were studied by breeding a dominant and a subordinate strain and crossing them. Both parents contributed equally to the dominance ranks of both sons and daughters. Cocks from the dominant strain were more aggressive and had bigger combs than cocks from the subordinate strain. Dominant cocks and hens, however, did not weigh more than subordinates.     

Competitive fighting for shells in the hermit crab,Clibanarius vittatus

The aggressive behavior of large Clibanarius vittatus against small C. vittatus was investigated. Large C. vittatus were more aggressive and showed fewer fear reactions in all conditions tested. The degree of dominance of large over small C. vittatus was much more marked and more predictable when the smaller crab occupied a Polinices rather than a Littorina shell and the large crab occupied a Littorina shell in both conditions. Evidence is given to suggest that C. vittatus reacts more to the shape than the size dimensions of a Polinices shell, and that small crabs occupying a Polinices shell are less active than other crabs occupying a Littorina shell.     

Rank and reproduction among female langur monkeys: Aging and improvement (They're not just getting older,they're getting better)

An investigation of the social rank, reproduction, and ages of adult female Indian gray langur monkeys (Presbytis entellus) living in two colony social groups revealed that rank based on displacements is neither correlated with nor best predicted by female age or reproductive value. The hierarchy of female ranks is best conceptualized as a layered ranking system in which there are clusters of females of the same dominance rank forming layers within the structure. Statistical significance in frequencies of displacement differs between but not within these layered groups of females. Factors such as group composition, presence of uterine kin, reproductive state, and individual personality are hypothesized to predict changes in female rank far better than does reproductive value. Our data show that reproductive success increases with age. The infant survival record for the six oldest females in our colony was much better than for the five youngest adult females.     

A multivariate analysis of social dominance in children

The social dominance behavior of dyads of unacquainted, same-sex 31/2 year-olds was observed in a familiar laboratory playroom under two conditions: A free play situation and a situation where candy was introduced. In each of the two conditions, a principal components analysis was used to explore two issues: the usefulness of the multivariate approach in devising a definition of dominance, and the cross-situational stability of the construct. In the free play session, the first principal component that emerged was consistent with a theoretical definition of dominance. This picture was disrupted by the introduction of candy in the second condition. However, a high correlation was found between the dominance hierarchies established in each situation. It was concluded that the multivariate analysis is a useful method for the study of dominance. The generalizability of social dominance across settings was discussed as a possible explanation for the high cross-situational stability.     

寻找丢失的自我——精神分裂症患者的自我面孔识别

为探索精神分裂症患者自我面孔识别的能力以及在视听整合任务中面孔对声音身份识别(同性和异性)的影响,选取34名住院精神分裂症患者和26名健康被试,分别进行单通道动态自我面孔识别任务、单通道自我声音识别任务和视听整合任务的3个实验。结果发现:精神分裂症患者的单通道自我面孔识别能力和自我声音识别能力与健康组无区别,但在视听整合任务中,精神分裂症患者的声音身份识别受到视觉通道面孔识别的影响。结果表明,精神分裂症患者有自我面孔识别的能力,自我面孔会促进自我声音的识别,并抑制对同性他人声音和异性他人声音的识别。     

A dual-process motivational model of attitudes towards vegetarians and vegans

Vegetarians and vegans comprise a minority of most western populations. However, relatively little research has investigated the psychological foundations of attitudes towards this minority group. The following study employs a dual process model of intergroup attitudes to explore the motivational basis of non-vegetarians' attitudes towards vegetarians and vegans. Participants were 1,326 individuals recruited through advertisements in a national newspaper in New Zealand. Non-vegetarian participants first completed measures of ideological attitudes and social worldviews, and then were randomly assigned to complete a measure of outgroup attitudes towards either vegetarians or vegans. Although non-vegetarians' attitudes towards both vegetarians and vegans were generally positive, attitudes towards vegans were significantly less positive than attitudes towards vegetarians, and male participants expressed significantly less positive attitudes towards both outgroups than female participants. The structural equation model predicting attitudes towards vegetarians and vegans fit the data well and explained a significant amount of the variance in attitudes.     

Authoritarianism,Social Dominance,and Other Roots of Generalized Prejudice

The search for the personological roots of generalized prejudice (or ethnocentrism) began with the authoritarian personality, but in recent years, the twin constructs of right‐wing authoritarianism and social dominance orientation have been widely treated as the dual processes that lead to generalized prejudice. However, studies conducted for this article show that other constructs, notably empathy and principled moral reasoning, contribute important additional variance. Whereas authoritarianism and social dominance positively predict generalized prejudice, empathy and principled moral reasoning are related negatively to it. For the final study, a structural model of these relationships was tested. To fully understand individual differences in the propensity for generalized prejudice, it is necessary to move beyond the dual processes union of authoritarianism and social dominance.     

Individual Differences in Testosterone Predict Persistence in Men

Persistence is an important predictor of future successes. The present research addresses the relationship between testosterone and persistence in men. One hundred eighteen men were randomly assigned to win or lose a competitive number tracing task against a confederate or complete the task alone in a non‐competitive control condition. Saliva samples were collected prior to and after the competition or control conditions. Participants were then given a maximum time of 30 min to spend attempting to solve unsolvable puzzles, with the option to quit at any time. In contrast to our prediction, changes in testosterone concentrations in response to the competitive interaction did not predict persistence behaviour. However, individual differences in testosterone concentrations (pre‐competition/non‐competition) were positively correlated with persistence. These findings are the first to examine associations between neuroendocrine function and persistence behaviour in people and suggest that testosterone should also be considered when predicting persistence‐related outcomes. Copyright © 2014 European Association of Personality Psychology