Studies on wild house mice iv: On the heredity of testosterone and readiness to attack

An attempt was made to determine the role of the Y chromosome in the development of aggression in wild house mice. The aggression-eliciting property of testosterone depends not only on circulating adult testosterone, but also on perinatal sensitization of the central nervous system to this steroid. Results of crosses between aggressive (SAL) and non-aggressive (LAL) mice indicate that adult plasma testosterone in these mice is determined by the autosomes, high testosterone levels being dominant over low levels. Conversely, the Y-chromosomal effect seems related to perinatal processes that sensitize the brain for testosterone.     

Antiaggressive and motor effects of the DA release inhibitor CGS 10746B

In the present study the effects of a wide range of doses of the dopamine release inhibitor CGS 10746B were evaluated in spontaneous activity and in aggressive behaviour using the paradigm of isolation‐induced aggression. The two higher doses (8 and 16 mg/kg) produced a decrease in spontaneous motor activity. Antiaggressive effects were observed after administration of doses from 4 mg/kg upwards. At this dose, CGS 10746B diminished threat and attack, and although an increase in immobility was observed, no impairment of other motor behaviours was presented. With higher doses, aggression was practically abolished but with a concomitant effect on many other behaviours. When animals were separated depending on their latency of attack, those that showed a long attack latency (LAL) presented a stronger response to 4 mg/kg than those that had a short attack latency (SAL), which were not affected in their aggression by this dose. We can conclude that presynaptic dopamine function is necessary for the normal expression of aggressive behaviours, since CGS 10746B reduces aggression at doses that do not affect spontaneous motor activity. Aggr. Behav. 27:382–390, 2001. © 2001 Wiley‐Liss, Inc.     

Violent phenotype in SAL mice is inflexible and fixed in adulthood

Violence was shown to be qualitatively different from functional hyper‐aggression in mice selected for high aggression namely Short Attack Latency (SAL), Turku Aggressive (TA) and North Carolina (NC900) strains. This study aimed at investigating whether this adulthood violent phenotype as seen previously in the SAL mice is fixed and hence behaviorally inflexible right from day 1 of the experiment or consequential, i.e., subject to gradual change from functional aggression to violence. The functionally hyper‐aggressive strains namely TA and NC900 strains served as controls for the study. Methodologically, behavioral (in)flexibility was studied using the overall sequential structure of agonistic behavior. In particular, intra‐individual variations in the overall agonistic behavior as well as offensive, pre‐ and post‐offensive behavior transitions, directly related to the resident–intruder interactions were investigated. The SAL mice showed the least intra‐individual variation in their overall sequential agonistic structure as well as a fixed offense‐oriented agonistic behavior of highest magnitude when compared with the other strains. Additionally, the pre‐ and post‐ offensive transitions were most salient in the functionally hyper‐aggressive TA and NC900 strains, whereas virtually absent in the SAL mice. Thus, the violent behavior of the adult SAL mice is behaviorally inflexible or fixed, whereas the functionally hyper‐aggressive behavior of the adult TA and NC900 mice is behaviorally flexible and constantly adaptive to the opponent behavior, over 3 days of repeated resident–intruder interaction. Aggr. Behav. 35:430–436, 2009. © 2009 Wiley‐Liss, Inc.     

Influence of the teacher-student relationship on childhood conduct problems: a prospective study.

Examined the influence of the quality of the teacher-student relationship on children's subsequent levels of aggression in a sample of 61 second and third-grade children nominated and rated by their teachers as aggressive. The stability of teachers' and children's reports of relationships quality across academic years was in the low to moderate range. Teachers and children showed little agreement in their reports of relationship quality. Teachers' and children's reports of relationship quality in year 1 (Y1) predicted teacher-rated aggression the following year, controlling for Y1 ratings of aggression. Teachers' reports of relationship quality across Y1 and Y2 predicted peer-rated aggression, but not teacher-rated aggression, in Y3, controlling for Y1 aggression. Consistent with a buffering role for teacher-student relationships, a positive teacher-student relationship was of greatest benefit to children whose mothers reported rejecting parenting histories. We discuss implications for school-based prevention programs.     

A Multimethodological Study of Preschoolers' Preferences for Aggressive Television and Video Games

The association between aggressive media and related behavior is complicated, and the role of underlying genetics has not been adequately explored. A better understanding of the role of genetics on the relationship between aggressive media and behavior, especially in young children, is critical. Using a twin/triplets sample (N = 184 children), the authors investigated the association between preschoolers' preferred media choices and their aggressive behaviors. A multimeasure methodology was utilized, examining children's reports of their preferred media games and shows, observed child negativity and aggression in the lab, and parent reports of their own and their children's aggressive behaviors. The results demonstrated a significant relationship between maternal aggression and parent-reported child aggression, especially for boys. Genetic analyses demonstrated significant heritability for children's parent-reported aggressive behaviors, supporting the biological basis of aggression, but not for media aggression preferences. Controlling for genetics, the authors found that the association between media preferences and aggressive behavior may be genetic in origin. These results emphasize the importance of considering shared genetics underlying the relationship between children's aggressive behaviors and their media preferences, as well as environmental influences. By examining preschoolers, the present study provides insight into the importance of media influences in children younger than those previously studied.     

Reciprocal influences between maternal discipline techniques and aggression in children and adolescents

Most studies assessing the link between parental discipline and child aggression have focused primarily on discipline as a cause and aggression as an outcome. In addition to the pathway from discipline to aggression, however, aggressive behavior on the part of the child may lead to future use of discipline by the parent. In this study, structural equation modeling was used to assess reciprocal influences over time between a mothers' use of discipline and aggression in children. Data were drawn from the Springfield Child Development Project, a longitudinal study of middle childhood and adolescence, focusing on antecedents of aggression. The original sample consisted of 440 mother-child dyads living in the city of Springfield, MA. Children in the sample were between 7 and 14 years of age at the first data collection period and between 12 and 19 years of age at the final data collection period. Four hypotheses were tested: (1) a mother's use of aggressive discipline predicts an increase in later child aggression, (2) child aggression predicts an increase in later use of aggressive discipline, (3) the use of reasoning predicts a decrease in later child aggression, and (4) child aggression predicts an increase in later use of reasoning. All hypotheses except number 3 were supported to some degree. Results suggest that children's early aggressive behavior leads to an increase in their mothers' use of both reasoning and aggressive discipline; in turn, increased use of aggressive discipline leads to an increase in aggression during both childhood and adolescence.     

The Y chromosome, social signals, and offense in mice

Offense is one type of aggression in mice (Mus musculus/Mus domesticus). Offense was measured in a panel of testers design for two congenic strains of mice. The two congenic strains were DBA1Bg and DBA1. C57BL10-YBg. These differ in the Y chromosome. Offense was measured for the following dyadic pairs: Group 1 (DBA1 tested against a DBA1 opponent); Group 2 (DBA1 tested against a DBA1.C57BL10-Y opponent); Group 3 (DBA1.C57BL10-Y tested against a DBA1.C57BL10-Y opponent); and Group 4 (DBA1.C57BL10-Y tested against a DBA1 opponent). Group 1 was more aggressive than Group 3, whereas Group 2 was no more aggressive than Group 4. Thus, when the experimental and opponent pairs have the same Y chromosome, the congenics differ in offense, whereas when the experimental and opponent pairs have different Y chromosomes, the congenics do not differ in offense. These findings are consistent with the hypothesis that these Y chromosomes affect the display of and response to social or other stimuli for offense of mice. These stimuli may be individual recognition chemosignals in urine.     

同伴地位对青少年早期不同类型攻击行为发展的影响:性别与班级规范的调节作用

采用同伴提名法,对2470名初二学生进行为期半年的追踪研究,考察两种同伴地位(社会喜好和社会支配)对三种攻击类型(身体、言语和关系攻击)发展的预测,以及性别与班级规范在其中的调节作用。多层线性分析发现:(1)社会喜好负向、社会支配正向预测个体半年后的三类攻击行为,且男生的社会喜好对关系攻击的预测作用强于女生;(2)对于男生而言,身体和言语攻击的班级规范强化个体后续的攻击行为,但关系攻击的班级规范则无显著影响;对于女生而言,身体攻击的班级规范强化个体后续的攻击行为,言语和关系攻击的班级规范强化初始攻击水平低的个体相应的攻击行为、而对于初始攻击水平高的个体表现出弱化效应;(3)班级规范还能调节社会支配对攻击行为的影响,在言语攻击规范高的班级中,社会支配对个体言语攻击的正向预测作用更强。     

Bidirectional Effects between Parenting and Aggressive Child Behavior in the Context of a Preventive Intervention

Over time, developmental theories and empirical studies have gradually started to adopt a bidirectional viewpoint. The area of intervention research is, however, lagging behind in this respect. This longitudinal study examined whether bidirectional associations between (changes in) parenting and (changes in) aggressive child behavior over time differed in three conditions: a child intervention condition, a child + parent intervention condition and a control condition. Participants were 267 children (74 % boys, 26 % girls) with elevated levels of aggression, their mothers and their teachers. Reactive aggression, proactive aggression and perceived parenting were measured at four measurement times from pretest to one-year after intervention termination. Results showed that associations between aggressive child behavior and perceived parenting are different in an intervention context, compared to a general developmental context. Aggressive behavior and perceived parenting were unrelated over time for children who did not receive an intervention. In an intervention context, however, decreases in aggressive child behavior were related to increases in perceived positive parenting and decreases in perceived overreactivity. These findings underscore the importance of addressing child-driven processes in interventions aimed at children, but also in interventions aimed at both children and their parents.     

When hockey parents are motivationally imbalanced: Passion,need satisfaction,and verbal aggression toward officials

Spectators can engage in high levels of verbal aggression toward youth hockey officials. Often, the perpetrators of this aggression are the parents. Our aim was to test the motivational factors involved in explaining why hockey parents sometimes take things too far and engage in verbally aggressive behavior toward officials. We reasoned that verbal aggression toward officials would be a function of two forms of motivational imbalance. First, in line with the dualistic model of passion, we hypothesized that verbal aggression would be positively associated with hockey parents’ obsessive passion, an imbalanced form of passion. Also, based on the compensatory model of passion, we predicted that obsessive passion would be associated with imbalanced psychological need satisfaction involving high need satisfaction from being a hockey parent, but low global need satisfaction. We administered online surveys to Canadian hockey parents (N = 992) assessing their verbal aggression toward officials, passion for being a hockey parent, and psychological need satisfaction from being a hockey parent and in general. Using structural equation modeling, we found support for a model in which high need satisfaction from being a hockey parent and low need satisfaction in general were associated with obsessive passion. Obsessive passion, in turn, was associated with greater verbal aggression toward referees. These findings help reveal why some hockey parents insult, threaten, and engage in other forms of verbal aggression toward officials. They also highlight the importance of maintaining motivational balance among sport parents.     

Y haplogroups and aggressive behavior in a Pakistani ethnic group

Studies show that personality dimensions such as aggression are influenced by genetic factors and that allelic variants located on the Y chromosome influence such behavior. We investigated polymorphisms on the male-specific region of the human Y chromosome in 156 unrelated males from the same ethnic background, who were administered the Punjabi translation of the Buss and Perry Aggression Questionnaire that measures four aspects that constitute aggressive behavior, i.e. physical aggression, verbal aggression, anger, and hostility. A value of .85 for Cronbach's coefficient alpha indicates considerable internal consistency and suggests that the psychometric properties of the aggression questionnaire can be adapted for the Pakistani population. A mean score+/-SD of 69.70+/-19.95 was obtained for the questionnaire. Each individual was genotyped following a phylogenetic hierarchical approach to define evolutionary Y haplogroups. Five Y haplogroups that are commonly found in Eurasia and Pakistan comprised 87% (n=136) of the population sample, with one haplogroup, R1a1, constituting 55% of the sampled population. A comparison of the total and four subscale mean scores across the five common Y haplogroups that were present at a frequency > or =3% in this ethnic group revealed no overall significant differences. However, effect-size comparisons allowed us to detect an association of the haplogroups R2 (Cohen's d statistic=.448-.732) and R1a1 (d=.107-.448) with lower self-reported aggression mean scores in this population.     

青少年的依恋、情绪智力与攻击性行为的关系

通过对370名青少年的问卷调查,考察情绪智力在亲子依恋与攻击行为之间关系的中介效应和调节效应。结果表明:(1)亲子依恋和情绪智力对青少年的攻击行为均具有保护作用,亲子依恋既直接影响青少年的攻击行为,同时又通过情绪智力对其产生间接影响。(2)情绪智力对亲子依恋与攻击行为的关系具有调节作用,亲子依恋的保护作用在高情绪智力的个体中比在低情绪智力的个体中更明显,支持了保护因子—保护因子模型。     

Unidimensionality and Developmental Trajectory of Aggressive Behavior in Clinically-Referred Boys: A Rasch Analysis

A majority of research investigating aggression and its development in children relies on rating scales such as the Child Behavior Checklist (CBCL). These scales typically are developed using a conventional factor analytic approach for the selection and retention of scale items, but may contain insufficient items to assess the unidimensionality and developmental trajectory of youths’ aggressive behavior. Rasch analysis was employed to determine the extent to which CBCL Aggressive and Delinquent clinical syndrome scale items reflect the unidimensionality and expected developmental trajectory of aggressive behavior based on parent endorsements of 455, 6 to 16 year old boys referred to community mental health centers. The two scales showed considerable promise as a unidimensional aggression scale and mimic the expected developmental pattern of aggressive behavior in extant literature. Future development of an aggressive CBCL dimensional subscale, however, must eliminate redundant and non-contributing items, and include severe aggressive behavior items exhibited by persistently aggressive youths.     

The moderating role of empathy in the association between parental support and adolescent aggressive and delinquent behavior

The present two‐wave longitudinal study addressed the role of affective empathy and parental support in aggressive and delinquent behavior in a sample of 323 adolescents (158 boys, 165 girls). Self‐report questionnaires were used to assess affective empathy, perceived support from parents, delinquency, and aggression. Guided by theories on children's differential susceptibility to socialization, we expected adolescents with different levels of empathy to vary in their responsiveness to parental support. In agreement with our hypothesis, empathy moderated the relation of perceived parental support with aggressive and delinquent behavior. Controlling for the effect of gender and for the stability of aggression and delinquency, higher perceived parental support was predictive of lower levels of aggression at age 15, but only for adolescents high in empathy. Remarkably, adolescents low in empathy not only appeared to benefit less from parental support, but even showed more aggression and delinquency at age 15 when they perceived their parents to be more supportive at age 14. Aggr. Behav. 38:368‐377, 2012. © 2012 Wiley Periodicals, Inc.     

The mediation effect of mentalization in the relationship between attachment and aggression on the road

Studies regarding aggression on the road are getting more frequent, due to the close relationship of these variables with risky behaviour and crash-related events. Whereas most of research has focused on both contextual and personality (proximal) variables, the current research aimed to explore the relationship between attachment styles (distal variables) and aggressive behaviour on the road, hypothesizing the mediation effect of mentalization. Then, a sample of 469 drivers (M_age = 35.60, SD_age = 12.38; 66.1% female) taken from the general Spanish population completed a set of measures about their attachment styles (secure, anxious, avoidant, and disorganized), mentalization (alexithymia, mindful attention, empathy, and emotion recognition), and aggressive behaviour on the road (verbal, physical, vehicle-use related, displaced, and adaptive aggression). The results showed that driving aggression variables were significantly associated with self-sufficiency attachment style, as well as with empathy, alexithymia, and mindful attention. A further SEM analysis suggested that mentalization did not mediate in the relationship between self-sufficiency and driving aggression, but significant indirect effects were obtained in the case of the association between preoccupation attachment style and each one of the ways of aggression. Clinical implications of the results are discussed, in terms of the possible effectiveness of mentalization-based therapies to reduce aggression on the road, especially those which refer to alexithymia and mindful attention.     

The impact of non‐aggressive behaviour early in aggressive interactions: Sex differences in direct and indirect aggression in response to provocation

Using an adapted form of the Taylor competitive reaction time task (TCRT: Taylor, 1967), we examined the effect of initially non‐aggressive behaviour during aggressive encounters. Specifically, if a person is initially non‐aggressive, but becomes more aggressive later, does an opponent respond more or less aggressively in response? Participants (N = 148) played a competitive reaction time task against a bogus partner, who was either initially non‐aggressive, or initially moderately aggressive, and then delivered increasingly loud noise blasts to participants on trials when the participant lost. Both direct (noise blasts delivered to the partner) and indirect aggression (damage to partner's reputation) were assessed. The impact of whether or not participants expected to meet the partner on direct and indirect aggression was also examined. All participants reduced their direct aggression towards an initially non‐aggressive partner and a partner they expected to meet. However, for females, the switch from initial non‐aggression to later aggression generated a negative evaluation of the partner, exhibited by indirect but not direct aggression.     

The importance of narcissism in predicting proactive and reactive aggression in moderately to highly aggressive children

The present study examined the importance of psychopathy-linked narcissism in predicting proactive and reactive aggression and conduct problems in a group of 160 moderately to highly aggressive children (mean age of 10 years, 9 months). Children's self-report of self-esteem and parent and teacher report of dimensions of psychopathy [narcissism, callous-unemotional (CU) traits, and impulsivity], proactive and reactive aggression, and conduct problems were collected. Composites of parent and teacher ratings of children's behavior were used. Consistent with the study's hypotheses, narcissism predicted unique variance in both proactive and reactive aggression, even when controlling for other dimensions of psychopathy, demographic variables associated with narcissism, and the alternative subtype of aggression. As hypothesized, impulsivity was significantly associated with only reactive aggression. CU traits were not related to proactive or reactive aggression once the control variables were entered. All dimensions of psychopathy predicted unique variance in conduct problems. Consistent with prediction, narcissism was not significantly related to general self-esteem, providing support that narcissism and self-esteem are different constructs. Furthermore, narcissism and self-esteem related differentially to proactive aggression, reactive aggression, and conduct problems. Furthermore, narcissism but not self-esteem accounted for unique variance in aggression and conduct problems. The importance of narcissism in the prediction of aggressive behaviors and clinical implications are discussed.     

Effects of movie violence on aggression in a field setting as a function of group dominance and cohesion.

In this quasi-experimental field study, delinquent members belonging to two cottages viewed aggressive commercial movies every evening for a week, while at the same time, subjects from two other cottages were exposed to neutral commercial movies. Behavioral observations were obtained through a nonhier-archical, minimally inferential procedure of a time-sampling nature; they were taken during a baseline week (at noon and in the evening), a treatment week (noon and evening) and a posttreatment week (noon). The main immediate effects of the violent films were an overall increase of both active behaviors and physical aggression; the effects on verbal aggression were more persistent but limited to one of the two cottages. On the other hand, more interactions occurred as an immediate consequence of viewing the films in both neutral treatment cottages; moreover, one of these two cottages also decreased its level of physical (short-term effect) and verbal (short- and long-term effects) aggression. In the aggressive treatment cottage, which was most affected, subjects who were most dominant, most popular, and least popular were influenced the most: an opposite effect was exhibited by those subjects who were judged as least aggressive by their peers. Complementary data are presented and discussed; the difference between the single individual laboratory paradigm and the existing group field paradigm is especially stressed.     

Differential effect of handling on adult aggression in male mice bidirectionally selected for attack latency

Individual variation in intermale aggression is to a significant degree based upon genetic variation, but environmental factors can also exert their influence on the level of aggression. Moreover, genotype–environment interactions are a well‐known phenomenon. In the present experiment, I tested whether cage size or handling during development had an influence on adult attack latency scores. To be able to study a genotype–environment interaction, mice from two bidirectionally on attack latency selected lines were used. The size of the cage in which the mice grew up had no long‐term effect on aggression, neither in the high‐ nor in the low‐aggressive line. Handling, however, significantly increased the adult aggression of males from the low‐aggressive line. Despite the differential effect of handling on genetically high‐ and low‐aggressive mice, handling was not able to undo the marked differences in attack latencies between mice from both lines. Aggr. Behav. 25:365–368, 1999. © 1999 Wiley‐Liss, Inc.     

Reactive and Proactive Aggression: Cross-informant Agreement and the Clinical Utility of Different Informants

The current study examined cross-informant agreement and clinical utility of parent and teacher ratings of reactive and proactive aggression (two functions of aggression) in the prediction of aggressive and rule-breaking behavior (two forms of aggressive behavior) in a clinically-heterogeneous referred sample. Reactive and proactive measures were significantly related to one another within informant. Furthermore, the reactive and proactive measures of aggression were significantly related across informants and resulted in differential predictions of emotion-focused aggressive and goal-directed rule-breaking behaviors in home and school settings. Both reactive and proactive functions of aggression predicted aggressive acts that were more emotion-focused, whereas only the proactive function of aggression predicted instrumental acts of aggression. The current findings suggest that setting-specific reports of functions and forms of aggressive behavior are valuable and that it may be premature to abandon the reactive and proactive aggression distinction.