Effects of peripheral immune activation on social behavior and adrenocortical activity in aggressive mice: Genotype-environment interactions

To explore genetic-developmental differences in the biobehavioral effects of induced illness, males from two lines of mice selectively bred for high or low levels of aggressive behavior were injected with endotoxin (Escherichia coli, LPS: 0.25 mg/kg, 1.25 mg/kg, or 2.5 mg, i.p.) or saline. Body temperature, weight, and locomotor activity were monitored immediately before and 8 and 24 hr after injection. Twenty-four hours after injection, social behaviors were assessed in a 10-min dyadic test, and hypothalamus, spleen, and serum were collected. In both lines, endotoxin treatment increased behavioral immobility ("freezing") and decreased social exploration. Other effects showed line differences: Males from the high-aggressive line had a lower threshold to endotoxin-induced effects on body temperature, weight loss, spleen weight, and corticosterone. Social reactivity (startle response to mild social investigation) increased in the high-aggressive line and decreased in the low-aggressive line after treatment. In the high-aggressive line only, endotoxin decreased attack frequency and increased latency to attack. The interactions between selected line (genotype) and endotoxin treatment (environment) demonstrate that genetic-developmental differences in social and aggressive behavior may indicate the extent to which immune stimuli (e.g., bacteria, viruses, cytokines) function as "biobehavioral stressors." Aggr. Behav. 23:93–105, 1997.© 1997 Wiley-Liss, Inc.     

Bullying as a group process: Participant roles and their relations to social status within the group

Bullying was investigated as a group process, a social phenomenon taking place in a school setting among 573 Finnish sixth-grade children (286 girls, 287 boys) aged 12–13 years. Different Participant Roles taken by individual children in the bullying process were examined and related to a) self-estimated behavior in bullying situations, b) social acceptance and social rejection, and c) belongingness to one of the five sociometric status groups (popular, rejected, neglected, controversial, and average). The Participant Roles assigned to the subject were Victim, Bully, Reinforcer of the bully, Assistant of the bully, Defender of the victim, and Outsider. There were significant sex differences in the distribution of Participant Roles. Boys were more frequently in the roles of Bully, Reinforcer and Assistant, while the most frequent roles of the girls were those of Defender and Outsider. The subjects were moderately well aware of their Participant Roles, although they underestimated their participation in active bullying behavior and emphasized that they acted as Defenders and Outsiders. The sociometric status of the children was found to be connected to their Participant Roles. © 1996 Wiley-Liss, Inc.     

A comparison of 8- and 11-year-old girls' and boys' participation in specific types of rough-and-tumble play and aggressive fighting: Implications for functional hypotheses

Study 1 compared the extent to which 8- and 11-year-old girls and boys (N = 86) participated in specific types of rough-and-tumble play. It used an observational methodology. The data were used to test two prominent hypotheses about the evolutionary function of this general category of play behaviour that have been applied to children, especially boys, of this age. One is that rough-and-tumble play provides practice for the development of real fighting skills and the other that it serves as a safe way to establish/display social dominance. Both hypotheses predict that boys will engage in more rough-and-tumble play than girls, especially those types that are used in fighting/dominance contests. Boys were found to engage in significantly more chase initiation activities, more bouts of brief rough-and-tumble play, more bouts of restraining and more bouts of boxing/hitting than girls. These data provide some support for the two hypotheses, although significant sex differences were not found for all types of rough-and-tumble play observed. No significant age differences were obtained, suggesting that the two hypotheses may be applicable throughout the 8- to 11-year-old period and not just at the end of it as previous research had suggested. Study 2 presented observational data concerning the motor patterns used in aggressive fighting. In all but one case, there were no significant differences in the extent to which 8/9- and 10/11-year-old girls and boys employed wrestling, hitting and restraining, supporting the view that the practice fighting hypothesis is relevant throughout the 8-11-year-old period. It was argued that age and sex differences provide a useful means of scrutinising functional hypotheses, and that splitting behavioural categories that contain disparate action patterns facilitates more refined tests of those hypotheses. © 1996 Wiley-Liss, Inc.     

睡眠不足对人际交互的影响及其认知神经机制

睡眠不足会对人的认知、情感和人际交互产生诸多影响。这种影响在社会情绪层面表现为个体情绪共情和认知共情的减少,易激惹性与愤怒情绪的增加;在社会行为层面则表现为亲社会行为的减少和攻击行为的增加。在睡眠不足状态下,情绪系统和认知系统功能连接的减弱可能是这些变化的潜在机制。未来应结合生态效度较高的睡眠操作手段,系统考察睡眠不足如何导致各种高级社会情绪的改变,以及这些社会情绪的变化如何导致社会行为的变化。     

Creative Fixation is No Laughing Matter: The Effects of Funny and Unfunny Examples on Humor Production

How do people come up with humorous ideas? In creative cognition research, exposure to good examples sometimes causes fixation (people get “stuck” on the examples) but other times sparks inspiration (people's responses are more creative). The present research examined the effects of funny and unfunny examples on joke production. A sample of 175 adults read scenarios that they completed with funny responses. All participants were instructed to be funny, but before responding they read (a) funny responses as examples of good responses to emulate, (b) unfunny responses as examples of poor responses to avoid, or (c) no examples. The participants’ own responses were rated for funniness and for similarity to the example responses, and response times were recorded. Reading either funny or unfunny examples, compared to no examples, caused people to come up with funnier jokes. Similarity to the examples was low in all conditions, so fixation was relatively modest, but people who saw unfunny examples spent more time coming up with their responses. Taken together, the findings support the growing literature showing that examples are often inspiring rather than constraining, and they imply that good and bad examples spark creative thought via different paths.     

Traumatic brain injury and adverse psychological effects: Examining a potential pathway to aggressive offending

Contemporary scholarship has demonstrated an association between traumatic brain injury (TBI) during adolescence and aggressive offending. Research, however, has yet to identify any mechanisms linking TBI to subsequent aggressive offending. Consequently, the current study hypothesized that adverse psychological effects is one such pathway. The current study used the Pathways to Desistance data set (n = 416) to examine the pathway of TBI to aggressive offending through adverse psychological effects. The findings of the structural equation model supported the hypothesized association. Specifically, increased exposure to TBI was indirectly associated with aggressive offending through adverse psychological effects. An additional supplemental analysis illustrated that a direct link between TBI and aggressive offending did not exist for the analytical sample. The findings suggested that the neurological disruptions commonly associated with TBI could result in direct increases in negative psychological outcomes and indirect increases in subsequent negative behavioral outcomes.     

Predictors of Symptom Outcome in Interpretation Bias Modification for Dysphoria

Interpretation Bias Modification (IBM) interventions have been effective in reducing negative interpretation biases theorized to underlie depressive psychopathology. Although these programs have been highlighted as potential short-term interventions for depression, mixed evidence has been found for their effects on depressive symptoms. There is a need to examine attitudes towards training as well as individual difference factors that may impact symptom outcomes for IBM depression interventions. Seventy-two dysphoric young adults were randomly assigned to receive either an IBM targeting negative interpretation bias in personal evaluations or interpersonal situations or a healthy video control (HVC) condition. Compared to those who received HVC, participants in the IBM condition reported lower negative interpretation bias at posttreatment. No differences between conditions were found for symptom outcomes. Greater perceived treatment credibility and expectancy were associated with better treatment outcomes for both the IBM and HVC groups. Within the IBM group, a greater tendency toward assimilation with treatment scenarios was significantly associated with better treatment outcomes for both depressive and anger symptoms. This effect was unique from treatment credibility and expectancy. Pretreatment psychological reactance did not predict treatment response for either condition. Implications and future research directions are discussed.