Psychopathy and Aggression: Examining the Role of Empathy

Empirical research has consistently demonstrated a positive association between psychopathic traits and physical aggression (Campbell, Porter, & Santor, 2004; Gretton, Hare, & Catchpole, 2004; Raine et aI., 2006; Spain, Douglas, Poythress, & Epstein, 2004). Moreover, research has also found that the emotional/interpersonal (Factor 1) psychopathy traits tend to be more closely associated with goal oriented, proactive aggression, whereas the social deviance (Factor 2) psychopathy characteristics have been more closely linked to reactive aggression, which is perpetrated in response to threat or provocation (Flight & Forth, 2007). Blair (2004; 2005; 2006) has recently proposed the Integrated Emotions Systems Model (lES), which posits that the association between Factor 1 psychopathy traits and proactive aggression is due to amygdala dysfunction leading to failed moral socialization. Consequently, individuals who exhibit Factor 1 psychopathy traits do not experience affective empathy in response to distress cues exhibited by others, thus, preventing the inhibition of proactive aggression. The current investigation sought to test this model by examining the associations among the emotional/interpersonal (Factor 1) psychopathy traits, proactive aggression, and affective empathy. After accounting for head injury, Factor 2 psychopathy traits, reactive aggression, and cognitive empathy, it was hypothesized that 1) Factor 1 psychopathy traits would predict proactive aggression, and 2) that affective empathy is a common cause of Factor 1 psychopathy traits, proactive aggression, and of the relationship between these two constructs. This hypothesis assumed that (a) affective empathy would uniquely predict Factor 1 psychopathy traits, (b) that affective empathy would uniquely predict proactive aggression, and (c) that affective empathy would account for the relationship between Factor I psychopathy traits and proactive aggression. The total sample consisted of 137 male undergraduate students. Participants completed measures of psychopathy (SRP III; Paulhus, Hemphill, & Hare, in press), aggression (PCS; Marsee, Kimonis, & Frick, 2004; RPQ; Raine et at, 2006), dispositional cognitive and affective empathy (BES; Jolliffe & Farrington, 2006; TES; Spreng, McKinnon, Mar, & Levine, 2009), and situational cognitive and affective empathy in response to neutral and empathy eliciting video clips. Physiological indices (heart rate & electrodermal activity) of affective empathy were also obtained while participants viewed the neutral and empathy eliciting videos. Findings indicated that Factor I psychopathy traits predicted proactive aggression. In addition, results demonstrated that affective empathy predicted both Factor I psychopathy traits and proactive aggression. However, the association between affective empathy and proactive aggression appeared to be dependent on the conceptualization and measurement of affective empathy. Conversely, affective empathy did not appear to account for the relationship between Factor I psychopathy traits and proactive aggression. Overall, results demonstrated partial support for the IES model. Implications of the results, limitations of the study and future research directions are discussed.

The Dynamic Interplay of Attachment and Temperament in Relation to Dimensions of Aggression

The current study examined whether overt and relational forms of reactive and proactive aggression were differentially related to adolescents’ temperament and attachment security. Measures of adolescents’ temperament, attachment security, and aggression were completed by 211 adolescents, ages 10–14, and their caregivers. Attachment security was consistently associated with all four dimensions of aggression, whereas proneness to frustration was found to be uniquely associated with reactive-overt aggression. Additionally, it was found that at lower levels of effortful control more secure attachment was related to lower levels of reactive-relational aggression. Results also indicated that, for girls, the relation between attachment and proactive-overt and proactive-relational aggression was only significant when effortful control was low. Conversely, for boys, the relation between attachment and proactive-overt aggression and proactive-relational aggression was significant when effortful control was high. Implications of these findings and limitations to the current study are discussed.

Demolishing the Competition: The Association between Competitive Video Game Play and Aggression among Adolescents and Young Adults

The link between video game play and aggression is an important issue as video games The link between video game play and aggression is an important issue as video games are the fastest growing form of entertainment in the world. Past research on this association has been focused primarily on the link between video game violence and aggression; however, this research has confounded the effect of video game violence versus competition on aggression. The main goal of the current dissertation, therefore, was to examine the short- and long-term associations between competitive video game play and aggression. In addition, the longitudinal work on this association to date has been limited to adolescent samples, but not young adults. Thus, the second goal of the dissertation research was to investigate whether video game play predicts aggression in the long-term among young adults in addition to adolescents. To address these goals, three studies were conducted. Study 1 consisted of a series of experiments examining the short-term effect of video game violence versus competition on aggression. Study 2 examined the long-term association between competitive video game play and aggression among adolescents, and Study 3 examined this long-term link among young adults, in addition to adolescents. Taken together, the results of the three dissertation studies converged to suggest that video game competition, rather than violence, may be a stronger predictor of aggression in both the short- and long-term. Overall, the current research represents an important advance in our understanding of the association between video game play and aggression, and leads to a new direction in the video game and aggression literature. are the fastest growing form of entertainment in the world. Past research on this association has been focused primarily on the link between video game violence and aggression; however, this research has confounded the effect of video game violence versus competition on aggression. The main goal of the current dissertation, therefore, was to examine the short- and long-term associations between competitive video game play and aggression. In addition, the longitudinal work on this association to date has been limited to adolescent samples, but not young adults. Thus, the second goal of the dissertation research was to investigate whether video game play predicts aggression in the long-term among young adults in addition to adolescents. To address these goals, three studies were conducted. Study 1 consisted of a series of experiments examining the short-term effect of video game violence versus competition on aggression. Study 2 examined the long-term association between competitive video game play and aggression among adolescents, and Study 3 examined this long-term link among young adults, in addition to adolescents. Taken together, the results of the three dissertation studies converged to suggest that video game competition, rather than violence, may be a stronger predictor of aggression in both the short- and long-term. Overall, the current research represents an important advance in our understanding of the association between video game play and aggression, and leads to a new direction in the video game and aggression literature.

The relationship between self-serving cognitive distortions and bullying behaviours among elementary school children /

The purpose ofthe study was to examine the relationshq) between self-serving cognitive distortions and involvement in bullying behaviours. While relationships were e}q)k)red for both bullies and victims, the bully represented the main focus ofthis research. The participants ofthis study were 206 elementary school children in grades 5, 6, 7, and 8 from a school board in South Western Ontario. Participants conq>leted a 2- part self-report questionnaire within a 1-week time period. Part I aimed to measure self-serving cognitive distortions, while Part II was designed to assess selfreports of bullying behaviours. Analyses revealed that a significant direct relationship existed between children's self-serving cognitive distortions and bullying others. More specifically, children's self-serving cognitive distortions were moderately correlated with bullying others (r = .50, p< 0.01). This finding was consistent for both male and female participants. In addition, significant moderate correlations also existed between each ofthe 9 subscales ofself-serving cognitive distortions and bullying others. In regard to the relationship between children's self-serving cognitive distortions and victimization, a low significant direct relationshq) was found (r = .22 p<0.01). This finding was consistent for both male and female participants. The results ofthis study are discussed in terms oftheir theoretical, as well as applied implications.

The social consequences of mild head injury and executive dysfunction /

Mild head injury (MHI) is a serious cause of neurological impairment as is evident by the substantial percentage (15%) of individuals who remain symptomatic at least 1-year following "mild" head trauma. However, there is a paucity of research investigating the social consequences following a MHI. The first objective of this study was to examine whether measures of executive functioning were predictive of specific forms of antisocial behaviour, such as reactive aggression, impulsive antisocial behaviour, behavioural disinhibition, and deficits in social awareness after controlling for the variance accounted for by sex differences. The second objective was to investigate whether a history of MHI was predictive of these same social consequences after controlling for both sex differences and executive functioning. Ninety university students participated in neuropsychological testing and filled out self-report questionnaires. Fifty-two percent of the sample self-reported experiencing a MHI. As expected, men were more reactively aggressive and antisocial than women. Furthermore, executive dysfunction predicted reactive aggression and impulsive antisocial behaviour after controlling for sex differences. Finally, as expected, MHI status predicted reactive aggression, impulsive antisocial behaviour, and behavioural disinhibition after controlling for sex and executive fimctioning. MHI status and executive functioning did not predict social awareness or sensitivity to reward or punishment. These results suggest that incurring a MHI has serious social consequences that mirror the neurobehavioural profile following severe cases of brain injury. Therefore, the social sequelae after MHI imply a continuum of behavioural deficits between MHI and more severe forms of brain injury.

Correlates and outcomes of severe bullying: internalizing maladjustments of adolescent bullies, victims and bully- victims

The current study examined the association between involvement in bullying and victimization and internalizing difficulties such as self-esteem, social anxiety, depression and body image. Possible gender differences were also examined. The participants, high school students from Southern Ontario (N=533), were drawn from a larger, data set as part ofa study that was completed by the Youth Lifestyle Choices: Community Research Alliance (YLCCURA). The students completed a self-report questionnaire on a number ofmeasures; including, bullying, victimization, self-esteem, social anxiety, depression and body image. The results of this study suggest that those students who self-identified as victims and bully-victims also report higher levels of anxiety and depression than controls and bullies. Severe victims and bullyvictims had a lower body image than severe bullies and controls, whereas severe bullies seem to have a higher body image score than controls. These results are relevant when considering treatments and interventions for students experiencing adjustment difficulties who may also be at risk for bullying victimization. The results also suggest that particular attention needs to be focused on those adolescents who play multi-roles in bullying situations (i.e., bully-victims), since these students may come to the attention ofthe school system for externalizing behaviours, but may also need assistance for internalizing maladjustments.

Individual differences and factors affecting male behaviour in field crickets

Individual differences in male sexual behav~our and the factors influencing calling behaviour were studied in the field crickets Gryllus 2 integer and Q. veletis. In a large (13m) outdoor arena individually numbered adult male ~~ integer started calling at three to five days of age but thereafter the age of individual G. integer males did not affect nightly calling duration. Calling also did not correlate with individual weight. In this study individual male calling was continuously distributed from 0 hrs. per night to 3.5 hrs. per night, on average. A temporal effect on the number of G. integer males calling was observed. The number of males calling through the night was uniform, but a sharp increase in the number calling was observed in the early morning. No difference in calling times was observed between the night and dawn callers. AlsC)' males calling at dawn usually didnotc'all during the preceeding night. Calling and reproductive success in 1979 demonstrated a negative logarithmic relationship while in the 1980(initial) population a negative linear relationship was observed. No relationship was seen in the 1980 high density population. The ratio of non-callers to callers also affected the mating of individuals in the 1979 and1980(initial) densities:-non~callers (males calling .5 hrs. per night, on average, or less) obtained more females when the population contained a high number of callers, this being a negative logarithmic relationship to, No such relationship was observed in the 1980 high density population. Individual displacement varied nightly and was not correlated to amount of calling or reproductive success of individual G. integer males. G. integer males were displa~ed more when in a higher density in the outdoor arena Male G. integer and G. veletis behaviours were also observed in an indoor arena at different densities and, in G. veletis, with respect to female presence. When females were present in the arena, in G. veletis, male calling was reduced. Males of both species called less, on average, when in ~ higher density, than when they were in a lower density. Male displacement of both species increased on average when in a higher density as compared to displacement in a lower density. Aggression was measured by aggressive call-ing and fighting and was studied in regards to density.G. integer demonstrated less aggression in all but one comparison at higher density. No difference was observed in the ratio of aggressive calling to f.ighting comparison in G. integer. G. veletis demonstrated mixed results. No difference in aggression between densities was observed in comparisons. Less.aggression did occur in higher densities when comparisons invol.ved fighting behaviour. Male behaviour represents a competitive strategy against ot~er males, strategy being defined as a genetic (in part) alternative to other strategies. In this sense, the factors of time, density, male-male aggression, and female presence are conditions demonstrated to affect male behaviour in G. integer and G. veletis. Individual male differences and other considerations suggest that alternative male behaviours are represented by at least two conditional strategies. This possibility, and the transient 'or stable nature of genetic polymorphisms in field cricket behaviour are considered.

The form and function of aggressive subtypes: Relations with the goodness of fit between adolescent temperament and parent personality

The current research investigated whether the interaction between adolescent temperament and parent personality, consistent with the goodness of fit perspective, differentially predicted overt (e.g., kicking, punching, insulting) and relational (e.g., gossiping, rumour spreading, ostracising) forms of reactive (e.g., provoked, a response to goal blocking, unplanned and emotional) and proactive (e.g., unprovoked, goal-directed, deliberate and relatively unemotional) aggression. Mothers, fathers and their adolescent child (N = 448, age 10-17) from southern Ontario, Canada filled out questionnaires on adolescent temperament (i.e., frustration, fear, and effortful control) and aggression. Parents reported on their own personality traits (i.e., agreeableness, conscientiousness, and emotional stability). The form and function of aggression not encompassed by the subtype under investigation were controlled in each regression analysis. Consistent with the hypothesis, results indicated that a poor fit between adolescent temperament vulnerabilities and lower parent personality traits, including agreeableness, conscientiousness and emotional stability, was predictive of greater levels of differentiated aggression. For instance, lower father conscientiousness strengthened the relation between higher frustration and reactive overt aggression. Unexpectedly in some cases, temperament risk factors were more strongly associated with aggression subtypes when personality scores were at higher levels, particularly agreeableness and conscientiousness, traits normally considered to be at the optimal end of the dimension. For example, higher father agreeableness strengthened the relation between higher frustration and reactive relational aggression. At the main effects level, low fearfulness was significantly associated with only the overt subtypes of aggression, and unexpectedly, higher frustration and lower effortful control were related to both proactive and reactive subtypes of aggression. A temperamentally vulnerable adolescent was also at greater risk of displaying aggressive behaviour when the father lacked emotional stability, but not the mother. These results are broadly consistent with the prediction that temperament risk factors are more strongly associated with aggression subtypes when an adolescent predisposition does not fit well with parent personality traits. Mechanisms pertaining to stress in the family environment and the fostering of self-regulation abilities are discussed with respect to why a poor fit between temperament and parent personality is predictive of adolescent differentiated aggression.

Facing Aggression: Cues Differ for Female versus Male Faces

The facial width-to-height ratio (face ratio), is a sexually dimorphic metric associated with actual aggression in men and with observers’ judgements of aggression in male faces. Here, we sought to determine if observers’ judgements of aggression were associated with the face ratio in female faces. In three studies, participants rated photographs of female and male faces on aggression, femininity, masculinity, attractiveness, and nurturing. In Studies 1 and 2, for female and male faces, judgements of aggression were associated with the face ratio even when other cues in the face related to masculinity were controlled statistically. Nevertheless, correlations between the face ratio and judgements of aggression were smaller for female than for male faces (F1,36= 7.43, p= 0.01). In Study 1, there was no significant relationship between judgements of femininity and of aggression in female faces. In Study 2, the association between judgements of masculinity and aggression was weaker in female faces than for male faces in Study 1. The weaker association in female faces may be because aggression and masculinity are stereotypically male traits. Thus, in Study 3, observers rated faces on nurturing (a stereotypically female trait) and on femininity. Judgements of nurturing were associated with femininity (positively) and masculinity (negatively) ratings in both female and male faces. In summary, the perception of aggression differs in female versus male faces. The sex difference was not simply because aggression is a gendered construct; the relationships between masculinity/femininity and nurturing were similar for male and female faces even though nurturing is also a gendered construct. Masculinity and femininity ratings are not associated with aggression ratings nor with the face ratio for female faces. In contrast, all four variables are highly inter-correlated in male faces, likely because these cues in male faces serve as ‘‘honest signals’’.

An exploration of the experience of implementing the second step violence prevention curriculum in one primary general learning disabilities class /

Violence has always been a part of the human experience, and therefore, a popular topic for research. It is a controversial issue, mostly because the possible sources of violent behaviour are so varied, encompassing both biological and environmental factors. However, very little disagreement is found regarding the severity of this societal problem. Most researchers agree that the number and intensity of aggressive acts among adults and children is growing. Not surprisingly, many educational policies, programs, and curricula have been developed to address this concern. The research favours programs which address the root causes of violence and seek to prevent rather than provide consequences for the undesirable behaviour. But what makes a violence prevention program effective? How should educators choose among the many curricula on the market? After reviewing the literature surrounding violence prevention programs and their effectiveness, The Second Step Violence Prevention Curriculum surfaced as unique in many ways. It was designed to address the root causes of violence in an active, student-centred way. Empathy training, anger management, interpersonal cognitive problem solving, and behavioural social skills form the basis of this program. Published in 1992, the program has been the topic of limited research, almost entirely carried out using quantitative methodologies.The purpose of this study was to understand what happens when the Second Step Violence Prevention Curriculum is implemented with a group of students and teachers. I was not seeking a statistical correlation between the frequency of violence and program delivery, as in most prior research. Rather, I wished to gain a deeper understanding of the impact ofthe program through the eyes of the participants. The Second Step Program was taught to a small, primary level, general learning disabilities class by a teacher and student teacher. Data were gathered using interviews with the teachers, personal observations, staff reports, and my own journal. Common themes across the four types of data collection emerged during the study, and these themes were isolated and explored for meaning. Findings indicate that the program does not offer a "quick fix" to this serious problem. However, several important discoveries were made. The teachers feU that the program was effective despite a lack of concrete evidence to support this claim. They used the Second Step strategies outside their actual instructional time and felt it made them better educators and disciplinarians. The students did not display a marked change in their behaviour during or after the program implementation, but they were better able to speak about their actions, the source of their aggression, and the alternatives which were available. Although they were not yet transferring their knowledge into positive action,a heightened awareness was evident. Finally, staff reports and my own journal led me to a deeper understanding ofhow perception frames reality. The perception that the program was working led everyone to feel more empowered when a violent incident occurred, and efforts were made to address the cause rather than merely to offer consequences. A general feeling that we were addressing the problem in a productive way was prevalent among the staff and students involved. The findings from this investigation have many implications for research and practice. Further study into the realm of violence prevention is greatly needed, using a balance of quantitative and qualitative methodologies. Such a serious problem can only be effectively addressed with a greater understanding of its complexities. This study also demonstrates the overall positive impact of the Second Step Violence Prevention Curriculum and, therefore, supports its continued use in our schools.

Bullying as a social process : factors influencing bystander behaviour

Bullying was approached as a social phenomenon in the present study. The central aim of this thesis was to uncover some of the factors that contribute to the attitudes and behavioural choices of bystanders during bullying situations. With this type of information, interventions can be tailored to change the behaviour of bystanders during bullying situations, and thus the ethos of the larger group. Thus, acting to alter the available sources of reinforcement for bullying behaviour and peer intervention attempts. Six hundred and twenty-six students participated. Students were sampled from grades 4 (n=140), 5 (n=l 13), 7 (n=205), and 8 (n=168). Students were measured for their involvement in bullying and victimization, as well as for involvement in the following bystander behaviours: encouraging, onlooking, defending, and seeking adult support. In addition, students were measured for tolerance of deviance, pro-victim attitudes, social anxiety and fear, and self-efficacy for peer intervention. Last, students were asked to complete a series of qualitative measures, including a series of hypothetical vignettes and open-ended questions. Analyses centered on the following areas: 1) rates of bullying, victimization, and bystander behaviour; 2) the influence of age and gender on bystander behaviour; 3) the characteristics associated with students who predominantly report involvement with defending, seeking adult assistance, encouraging, and onlooking behaviour; and 4) the influence of past involvement with bullying and victimization on bystander behaviour. b .--' -i . k Rates of bullying, victimization, and bystander behaviour were comparable to findings in the existing literature, where male students were more likely than female students to report involvement in both bullying and victimization. Boys were more likely than girls to report participation in encouraging and onlooking behaviours, while being less likely to report involvement in defending and seeking adult assistance. Partly consistent with existing findings, older students were more likely to report involvement in bullying, encouraging, and onlooking behaviour than younger students, who were more likely to report victimization, defending, and seeking adult assistance. Self-identified encouragers and onlookers reported a similar array of characteristics, in that they tended express high levels of tolerance of deviance, while expressing low levels of pro-victim attitudes and self-efficacy for peer intervention. Likewise, self-identified defenders and seekers of adult assistance tended to report a similar array of characteristics to each other, in that they tended to report low levels of tolerance of deviance, while expressing high levels of pro-victim attitudes and self efficacy for peer intervention. Additionally, self-identified bullies and self-identified bully-victims tended to report increased involvement in encouraging and onlooking, whereas self-identified victims tended to report increased involvement in defending behaviour and seeking adult assistance. Results are discussed in terms of implications for bullying prevention and intervention. Specifically, evidence from the present study suggests that as bystanders, students predominantly act to either support bullying acts or to support the victims of these acts, or alternatively, to actively remain outside bullying situations. Thus, encouraging students to make small changes in the way they express these sentiments during bullying situations would act to alter the culture of the larger peer group and the sources of reinforcement available for bullying acts as well as peer intervention attempts.

A comprehensive examination of adolescent gambling

The purposes of this study were: a) to examine the prevalence and consequences associated with adolescent gambling, b) to examine the factors which influence adolescent gambling,. c) to detennine what factors discriminate among four groups of gamblers (no-risk/non-gamblers, low-risk gamblers, at-risk gamblers, and high-risk/problematic gamblers), and d) to examine the relation of gambling to nine other risk behaviours (i.e., alcohol use, smoking, marijuana use, hard drug use, sexual activity, minor delinquency, major delinquency, direct aggression, and indirect aggression). Adolescents (N = 3,767) from 25 secondary schools completed a twohour survey that assessed involvement in risk be~aviours as well as potential predictors from a wide range of contexts (school, neighbourhood, family, peer, and intrapersonal). The majority of adolescents reported gambling, although the frequency of gambling participation was low. The strongest predictors/discriminators of gambling involvement were gender, unstructured activities, structured activities, and risk attitudes/perceptions. In addition, the examination of the co-occurrence of gambling with other risk behaviours revealed that for high-risk/problem gamblers, the top three most frequent co-occurring high-risk behaviours were direct aggression, minor delinquency and alcohol. This study was the first to examine the continuum of gambling involvement (i.e., non-gambling to high risk/problematic gambling) using a comprehensive set ofpotential predictors with a large sample of secondary school students. The findings of this study support past research and theories (e.g., Theory of Triadic Influence) which suggest the importance ofproximal variables in predicting risk behaviors. The next step, however, will be to examine the direct and indirect 1 effects of the ultimate (e.g., temperament), distal (e.g., parental relationship), and proximal variables (e.g., risk attitudes/perceptions) on gambling involvement in a longitudinal study.

Mating behaviours of the field cricket (Gryllus integer) at different levels of male density

The reproductive behaviour of the field cricket, Gryllus integer, was systematically observed in indoor arenas to determine the extent of female Choice and male-male competition at different sex ratios representing two male densities (12:6 and 6:6). The costs and benefits to males and females in those two densities were analyzed according to the theory of the evolution o£ leks. Observations were conducted during the dark hours when most calling occurred since hourly rates of courtship song and mating did not fluctuate significantly over a 24 h period. Female mating rates were not significantly different between densities, therefore males at high densities were not advantaged because of increased female tendencies to mate when social stimulation was increased. Mean rates of acoustical signalling (calling and courtin"g) did not differ significantly between densities. Mean rates of fighting by males at the high density were significantly greater than those of males at the low density. Mating benefits associated with callin~courting and fighting were measured. Mating rates did not vary with rates of calling at either density. Calling was not a prerequisite to mating. Courtship song preceded all matings. There was a significant power fit between male mating and courting rates, and male mating and fighting rates at the low, but not at the high, density. Density differences in the benefits associated with increased courting and fighting may relate, in part, to greater economic defensibility and monopoly of females due to reduced male competition at the low density. Dominant males may be preferentially chosen by females or better able to monopolize mating opportunities than subordinate males. Three criteria were used to determine whether dominant males were preferentially chosen by females. The number of matings by males who won fights (within 30 min of mating) was significantly greater than the number of matings by males who were defeated in such fights. Mating rates did not vary significantly with rates of winning at either density. There was a significant power fit between male mating rates and the percentage of fights a male won (irrespective of his fighting-frequency) at the low density. The mean duration a male guarded the female after mating did not vary significantly between densities. There was a significant linear relationship between the duration a spermatophore was retained and the duration a male guarded the female after mating. Courtship song apparently stimulated spermatophore removal. Male guarding involved inter-male aggression and reduced courtship attempts by other males. Males at the high density received no apparent reproductive benefits associated with increased social stimulation. Conclusive evidence for preferential choice of males by females, using the criteria examined here, is lacking. Males at the lower density had fewer competitors and could monopolize females more effectively.

Reproduction in the temperate crayfish, Orconectes rusticus: intermale aggression, copulatary behaviour, and sperm competition

The chelipeds of Orconectes rusticus are sexually dimorphic; males possessing the larger. Males use their chelae in intermale aggressive interactions, both to threaten, and assault opponents. In dyadic interactions males with larger chelae were dominant over otherwise physically similar opponents. A high frequency of attack behaviour, coupled with a low frequency of threats during these interactions indicates that actual physical contact is required for opponent assessment. Large clawed males oriented females into the copulatory position faster than small clawed males. Females more frequently escaped the precopulatory-grasp attempts of small clawed males. Additionally, male-female pairs that included a large clawed male remained in copula longer than pairs that included a small clawed male. Sperm of the second male to mate took precedence over the sperm of the primary male. Sperm precedence was incomplete; about 900/0 paternity accrued to the second male.

Personality and neuropsychological factors involved in females' relational aggression

The personality and neuropsychological factors associated with relational aggression were examined in a group of30 grade 6,7, and 8 girls identified through cluster analysis as being highly, yet almost exclusively, relationally aggressive and a group of 30 nonaggressive matched controls. Parents of the students in both groups completed the Coolidge Personality and Neuropsychological Inventory (1998), a 200- item DSM-IV -TR aligned, parent-as-respondent, standardized measure of c.hildren' s psychological functioning. It was found that high levels of relational aggression, in the absence of physical and verbal aggression, were associated with symptoms of DSM-IV - TR Axis I oppositional defiant disorder and conduct disorder and a wide variety of personality traits associated with DSM-IV -TR Axis II paranoid, borderline, narcissistic, histrionic, schizotypal, and passive aggressive personality disorders. Implications of these findings for theory, practice, and further research are discussed.