Dominance-subordinance in cohabiting pairs of adult rats: Effects on Aggressive behavior

Following an initial intruder aggression test, 10 pairs of adult male rats matched on aggressiveness were formed. The first 20 min of paired cohabitation were used to determine dominance and subordinance between pau members. Residents judged to be dominant from this observation session gained significantly more weight during cohabitation and exhibited significantly more aggression on the second aggression test than their subordinate counterparts. Significant correlations among various measures of aggression were found, but open field performance did not correlate, with the measures of aggression nor did changes in open field scores reflect changes in aggression.     

研究心理理论的新方法——失言识别任务

心理理论是对他人心理状态进行推论的能力。考察心理理论的经典范式是错误信念任务, 而青少年和成人在这种任务上可能出现天花板效应。为了测量青少年和成人的心理理论, Valerie E. Stone和她的合作者设计了失言识别任务。征求了Stone意见, 对失言识别任务的提出、构成、使用进行了介绍, 说明了该任务相对于经典范式的优势; 与此同时, 分析了失言识别任务范式存在的一些问题, 比如其效度指标问题, 与言语能力的分离问题, 失言识别任务与执行功能之间的分离等。未来研究可以尝试编制失言识别任务的本土化的量表, 并利用其探讨年长个体心理理论水平发展变化的规律。     

5～8岁儿童对模糊信息具有多重解释的理解

参照Carpendale和Chandler的实验范式,研究儿童对于“人们可能对同样信息给出不同解释”这一现象的理解,考察5~8岁儿童的解释性心理理论的发展。结果表明,5岁儿童不能理解心理过程的解释性,认为同样的信息只有一种合理的解释。从6岁开始,儿童才认识到,模糊信息可以有多种解释,但6、7岁时的这种理解并不完善,成绩随着任务要求而变化。8岁儿童才有比较稳定的解释性心理理论。     

儿童理解误信念的心理机制假设

儿童心理理论是近20年来发展心理学研究热点,对其研究主要是在误信念实验范式之下进行的。儿童理解误信念的心理机制问题是误信念研究的核心问题之一,研究者从不同的角度出发,采用不同的方法,提出了儿童如何理解误信念的几个重要假设,包括：元表征假设、事实掩盖假设、心理理论机制假设、计算资源假设。此文综述了这些假设,以期借鉴使用。     

Women Behaving Badly: Gender and Aggression in a Military Town, 1653–1781

Magistrates records from the English town of Portsmouth show the towns women to have been exceptionally violent. Women accounted, on average, for just over 31% of all assaults on record for the years 1653 to 1781. We used a combination of quantitative and qualitative methods to compare the fighting styles of men and women and to examine the extent to which these were gendered. Particular attention was paid to levels of violence between pairs of brawlers. The most common form of violence was male-on-male (2,666 cases), followed by female-on-female (1,690), male-on-female (1,675), and female-on-male (299). Of these pairings, female-on-male assaults were the most violent, as measured by the types of weapons used by the aggressors, and female-on-female pairings were the least violent.Funding was provided by grant 410-2000-0467 from the Social Sciences and Humanities Research Council of Canada. The authors are profoundly grateful to the gracious and highly capable staff of Portsmouths Museums and Records Service, including, most notably, Michael Gunton, Diana Gregg, Donna Malcolmson, and Sarah Speller. Special thanks also go to the team of volunteers who transcribed the towns sessions papers, thus greatly facilitating our entry of the same into a database. They were, in alphabetical order, Kate Beatty, Barbara Gower, Ursula Heinrich, Pam Honeysett, George Hothersall, Marjorie Hothersall, Una Lowe, Betty Richardson, Marjorie Ripper, and Brenda Whorton. There was one other volunteer: an inmate at the Kingston Prison just outside Portsmouth. Back in Toronto, several more people assisted in entering the records into a database. They were, in alphabetical order, Joanne Cordingley, James Hewitson, Allyson Lunny, Yvonne Pelletier, and Victoria Vaag.     

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.     

Impact of artificial fissioning and social networks on levels of aggression and affiliation in primates

Levels of aggression may be affected by stability of social relationships or by population density. A number of studies of nonhuman primates have indicated that spatial density influences agonistic activity levels less than does social density. Artificial fissioning of a captive troop of rhesus macaques was undertaken and the resultant differences in patterns of aggression and affiliation were examined. If population density has a major effect on levels of aggression, then fissioning will result in a decrease in aggression; if social stability has a major effect on levels of aggression, then fissioning is likely to be accompanied by an increase in aggression. An increase in rates of both aggressive and affiliative behavior resulted from artificial troop fissioning. These findings concur with other studies that have concluded that social stability is a more important determinant of primate aggression than is population density. Nonhuman primates use affiliative mechanisms to adjust their behavior when population density increases such that potentially adverse consequences of crowding are avoided.     

Person perception from changing emotional expressions: primacy,recency, or averaging effect?

ABSTRACT

Dynamic changes in emotional expressions are a valuable source of information in social interactions. As the expressive behaviour of a person changes, the inferences drawn from the behaviour may also change. Here, we test the possibility that dynamic changes in emotional expressions affect person perception in terms of stable trait attributions. Across three experiments, we examined perceivers’ inferences about others’ personality traits from changing emotional expressions. Expressions changed from one emotion (“start emotion”) to another emotion (“end emotion”), allowing us to disentangle potential primacy, recency, and averaging effects. Drawing on three influential models of person perception, we examined perceptions of dominance and affiliation (Experiment 1a), competence and warmth (Experiment 1b), and dominance and trustworthiness (Experiment 2). A strong recency effect was consistently found across all trait judgments, that is, the end emotion of dynamic expressions had a strong impact on trait ratings. Evidence for a primacy effect was also observed (i.e. the information of start emotions was integrated), but less pronounced, and only for trait ratings relating to affiliation, warmth, and trustworthiness. Taken together, these findings suggest that, when making trait judgements about others, observers weigh the most recently displayed emotion in dynamic expressions more heavily than the preceding emotion.     

Communicative factors,conflict progression,and use of reconciliatory strategies in pre‐school boys‐a series of random events or a sequential process?

Affiliative interactions between former opponents soon after a conflict, in non‐human primates and pre‐school children, have been documented to be followed by a reduction of future aggression and stress reactions, and to promote tolerance between individuals. The phenomenon has, therefore, been called reconciliation. Studies of non‐human primates have shown that the conflict cause can influence the reconciliatory outcome, and whether the aggressor or the victim of the aggression is more likely to take the initiative to reconcile, can differ between species. Few studies in pre‐school children have addressed how factors preceding the post‐conflict period, such as social interactions before the conflict outbreak, or the cause of the conflict, may be related to the likelihood of reconciliation, conflict progression, and conflict outcome in the form of possible continuation or initiation of interactions. Twenty boys were video‐recorded during free‐play at six pre‐schools. The existence of social interaction between the opponents in the upcoming conflict was examined in the pre‐conflict period. The observed causes of conflict were determined and classified into five categories. The affiliative behaviors identified in the post‐conflict period were classified into six categories. Finally, whether or not conflicts were followed by communicative exchanges in the succeeding non‐conflict period was documented. The results revealed that the cause of the conflict is associated with whether opponents had established social interaction prior to conflict in the pre‐conflict period. Acceptance rates (for the various categories of affiliative behaviors) appeared to differ. A non‐random pattern of conflict progression was apparent, suggesting the conflict cause was related to the category of reconciliatory strategy shown by the individuals. The aggressor and the victim initiated reconciliation at similar rates, with the exception of verbal apologies, which were initiated most often by the aggressor. Finally, the data also showed that higher frequencies of social interaction between former opponents in the succeeding non‐conflict period were associated both with whether or not social interaction had occurred in the pre‐conflict period, and whether or not the conflict was reconciled. In conclusion, communicative factors preceding conflicts, and conflict cause, are distinctively correlated with both the use and the outcome of post‐conflict affiliation in pre‐school boys. Aggr. Behav. 00:000–000, 2005. © 2005 Wiley‐Liss, Inc.     

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.