Lesions of the ventral hippocampus, but not the dorsal hippocampus, impair conditioned fear expression and inhibitory avoidance on the elevated T-maze

The hippocampus has been suggested to be involved in spatial (or configural) memory and also in the inhibition of certain response or goal alternatives. An increasing number of anatomical, physiological, and behavioral studies indicate that the hippocampus is functionally heterogeneous along the dorsal-ventral axis. Identification of distinct behavioral roles for the dorsal (DH) and ventral (VH) hippocampus may resolve differences between the various theoretical accounts of hippocampal function. The present study examined the effects of electrolytic lesions restricted to the DH or VH on fear-conditioned freezing, passive avoidance on the elevated T-maze (ETM) test of anxiety, and general activity in male Sprague-Dawley (Charles-River derived) albino rats. We found that rats with lesions of the VH, but not DH showed reduced freezing to both context and tone conditioned stimuli (CS). Rats with VH lesions also showed a reduced latency to emerge from the enclosed arm on trials 2 and 3 of the ETM (indicating reduced anxious behavior), while having no effect on the latency to escape from the open arms on trial 4. There were no differences in activity between the groups. These results indicate that the VH and DH are differentially involved in passive avoidance on the ETM and conditioned freezing to context and tone CS. We suggest that the VH may be specifically involved in modulating goal-oriented, defensive behavior expression through hypothalamic and amygdaloid connections.     

Importance of considering testosterone-cortisol interactions in predicting human aggression and dominance

A novel "field" study recently published in Aggressive Behavior found that individual differences in baseline testosterone concentrations were positively correlated with endorsement of political aggression and that baseline cortisol concentrations were negatively correlated with self-reported aggression among Palestinian boys living in Gaza. Here, we discuss recent evidence indicating that testosterone and cortisol interact to predict competitive, aggressive, and dominant behaviors and urge researchers collecting both hormones to perform and report analyses that formally test for such interaction effects.     

视觉表象扫描加工中的认知控制

通过建构一个反向扫描任务而形成任务冲突,在3个实验中考察了视觉表象扫描中认知控制与冲突解决机制。结果发现:(1)视觉表象扫描中出现了任务冲突效应;(2)外源性认知控制增强降低了任务冲突效应,但不影响扫描效率;(3)内源性认知控制增强既降低了任务冲突效应,也提高了反向扫描任务扫描效率。这些结果证实视觉表象扫描中存在一个认知控制机制,并发展了现有冲突解决理论。     

Extending the Theory of Realistic Conflict to Competition in Institutional Settings: Intergroup Status and Outcome

Abstract

The authors analyzed the extent to which the Theory of Realistic Conflict can be extended to institutional settings in which groups are not actively involved in decisions but are passive targets of decisions taken by an institutional authority (the rector). A negative interdependence between the in-group (psychology) and a high- or low-status out-group (engineering versus nursing) was established by an institutional authority (the rector). The competition (induced by the rector) was beneficial (an increase in the budget previously invested in the faculty) or detrimental (a decrease in the budget) for the in-group. The results confirmed that competition affects mutual attitudes, images, and behaviors of groups even if the groups are passive targets of decisions that the institutional authority makes. Moreover, competition—regardless of whether beneficial or detrimental—deteriorated images of and attitudes toward high-status out-groups. In contrast, competition improved images and opinions about low-status out-groups, but only in the loss condition.     

Developing work–family balance through conflict management*

An often‐neglected perspective is that work–family incompatibilities are not only intrapersonal role conflicts but also typically involve interpersonal conflicts. This study adopts an episodes approach and uses the theory of cooperation and competition to understand the interaction that promotes resolving work–family conflict incidents. Two‐hundred and four Chinese dual‐career parents each described a specific work–family conflict incident and responded to specific questions to code the interaction. Structural equation analyses indicated that cooperative goals facilitated constructive controversy that in turn promoted high quality resolutions, strong relationships, and confidence in the future of their work and family lives.     

Embedding social dilemmas in intergroup competition reduces free-riding

We study a class of multi-level collective actions, in which each individual is simultaneously engaged in an intragroup conflict and intergroup competition. The intragroup conflict is modeled as an n-person Prisoner’s Dilemma game, in which the dominant strategy is to contribute nothing. The intergroup competition is for an exogenous and commonly known prize shared by members of the winning group. We focus on the effects on the level of contribution of the two most common sharing rules for dividing the prize, equal and proportional. Our results show that (1) embedding the intragroup conflict in intergroup competition markedly reduces free riding; (2) the proportional profit sharing rule significantly outperforms the egalitarian rule, and the difference between the two increases with experience; (3) under egalitarian but not under proportional sharing, there is over-contribution compared to theoretical predictions, and (4) a simple reinforcement-based learning model accounts for the aggregate results of all five experimental conditions.     

动词隐含因果关系在代词解决中的作用及时间进程

以大学生为被试,通过三个实验来探讨动词隐含因果关系在代词解决中的作用及其时间进程。结果表明,动词隐含因果关系在代词解决中具有重要作用,特别是偏向NP2的动词具有强烈的导向作用,这种作用在代词解决的过程中,并不是在遇到代词后立即产生,而是在整合的过程中生效。     

Clinical Ethics: Theory Or Practice?

This article starts with a brief historical account of the ongoing debate about the status of clinical ethics: theory of practice. The author goes on to argue that clinical ethics is best understood as a practice. However, its practicality should not be measured by the extent to which clinical-ethical consultants manage to mediate or negotiate resolutions to ethical conflicts. Rather, clinical ethics is practical because it is characterized by a profound concern for the well-being of individual patients as well as the moral parameters of swift and urgent medical action in the face of limited supportive information.     

Effects of reward distribution and performance feedback on competitive responding

To implement competitive contingencies, one must select a distribution of unequal rewards and a schedule of feedback for competitors regarding one another's performance. This study investigated three bases for distributing rewards and two performance feedback conditions. Pairs of college students competed over a series of 2-min contests in which the competitive response was a knob pull. A sum of money was divided using a proportional distribution or one of two fixed reward distributions. In the proportional distribution, a subject's proportion of the sum was his or her proportion of the total number of responses. The two fixed distributions were divisions of 100%/0% or 67%/33%. Also, in every contest either subject could make a response that would end the contest prematurely and give both subjects the same amount—a sum equal to 33% of the competitive total. In the two feedback conditions, cumulative responses by each subject were either shown to both subjects during the contest or were not shown. The proportional distribution was clearly superior to either of the fixed distributions in number of responses produced across contests. The proportional distribution with feedback produced the largest number of competitive responses, and the 100%/0% distribution without feedback produced the smallest number. Differences among distributions typically emerged only during later blocks of contests. Fixed distributions of rewards often produced decelerating rates of responding, with losing competitors ending the contests before they were completed. Response-rate decreases were greatest for pairs in which the 2 subjects differed most in their response rates and proportion of wins. The presence of feedback had a small effect, increasing responding for some pairs in the 100%/0% distribution. Performance patterns were interpreted in terms of the consequences arranged for the individual participants by the reward distributions and differences in performance between competitors.