An aggression machine I. The intensity of aggressive defence aroused by aggressive offence

PitkÄnen, L. An aggression machine. I. The intensity of aggressive defence aroused by aggressive offence. Scand. J. Psychol., 1973, 14, 56–64.-Sixty 9-year-old boys were tested with an aggression machine (PAM) designed by the writer. PAM allows the variation of both S (light) and R (pressing a button) intensities. The stimuli and responses were given the designations of offensive and defensive aggression, respectively. The following main hypotheses were supported: (1) The intensity of impulsive aggressive defence to an aggressive offence was adapted to the intensity of attack. (2) The intensity of aggressive defence was determined by the authority of the attacker, the defence being strongest when the attacker was a person of the same age and status, and least vigorous when the attacker was a figure of authority or a weaker person. (3) The correlations of the intensity of aggressive defence against different attackers depended on the similarity of their social position; the correlations were higher the closer the position.     

An aggression machine: IV. Concurrent and predictive validity over ten years

The subjects (60 boys) were drawn from the sample of a longitudinal study of social development to represent extremely aggressive, anxious, constructive, and submissive patterns of behaviour at the age of 8. A year later they were tested with an aggression machine (PAM). This allows variation of the intensity of both aggressive attack and defence in different stimulus conditions. The intensity of defensive aggression towards different attackers as well as the response style variables, latency, duration, and number of responses were correlated with observed and self-reported data at the ages of 8, 9, 14 and 19. The results showed that the intensity of aggression toward a same-sex peer had the highest validity. Opposite sex and authority figures as attackers called up other associations and motives, such as conflicts with the mother and anxiety. From the response style variables the highest validity was obtained for reaction time. This correlated with constructive behaviour.     

Mousekilling,intermale fighting,and conditioned emotional response in rats

Several possible relationships between two forms of aggression in rats were studied. First, mouse killing and spontaneous intermale fighting were found to be correlated. Rats which attacked other rats were those most likely to kill mice. To determine whether aggressive and nonaggressive rats were also differentially responsive to other situations involving emotional arousal, but not aggression, mouse-killers and nonkillers were compared in a conditioned emotional response (CER) situation. Mouse-killers showed greater suppression to the conditioned stimulus (CS) and to the situational cues of the apparatus. Therefore, a common arousal mechanism may underlie a number of diverse agonistic responses. Nevertheless, extensive mouse-killing experience did not increase the tendency of rats to fight with either adult males or juvenile males.     

Are Children's Concerns About Punishment Related to Their Aggression?

Although moral reasoning is recognized as an influence on students' behavior, it is often overlooked in policies and interventions developed to change their behavior. Relations between specific types of moral reasoning (i.e., imminent, probable, physical, and psychological) and teacher-reported overt aggression were examined in 203 first and second graders. Regression analyses indicated that psychological reasoning explained a significant amount of the variance in overt aggression. Follow-up analyses indicated that overtly aggressive boys demonstrated more concern for the imminent consequences of their behavior on themselves (e.g., punishment) and less concern for the psychological consequences of their actions on others (e.g., hurting others' feelings) than nonaggressive boys. Implications for the prevention and treatment of aggressive behavior are discussed.     

The best friendships of aggressive boys: relationship quality, conflict management, and rule-breaking behavior

The current study examined the best friendships of aggressive and nonaggressive boys (N = 96 boys, 48 dyads, mean age = 10.6 years). Friends completed self-report measures of friendship quality, and their interactions were observed in situations that required conflict management and provided opportunities for rule-breaking behavior. Although there were no differences in boys' self-reports of friendship quality, observers rated nonaggressive boys and their friends as showing greater positive engagement, on-task behavior, and reciprocity in their interactions compared with aggressive boys and their friends. Aggressive boys and their friends provided more enticement for rule violations and engaged in more rule-breaking behavior than did nonaggressive boys and their friends. Also, the intensity of negative affect in observed conflicts between aggressive boys and their friends was greater than that between nonaggressive boys and their friends. The findings suggest that friendships may provide different developmental contexts for aggressive and nonaggressive boys.     

Aggression in African-American boys: a discriminant analysis.

The main purposes of this study were to determine whether familial variables found to be related to the development of aggressive behavior in Caucasian boys may also be related to similar aggressive patterns in inner-city African-American boys and to assess the relative importance of these variables for classifying the subject population into aggressive and nonaggressive groups. Discriminant analyses were performed using 83 African-American boys, with a mean age of 13.9 years, who were classified as institutionalized aggressive, noninstitutionalized aggressive, and noninstitutionalized nonaggressive subjects. Although the same father and mother variables were used in the analyses, the father variables were not related to group membership. Furthermore, the results showed that both groups of aggressive boys reported more aggression within as well as outside their family home settings than their nonaggressive counterparts. Socioeconomic-related factors such as employment status of parent(s), size of family, and number of parents in the household were not useful predictors of aggressive and nonaggressive group membership.     

When Social Situations Take a Turn for the Worse: Situational and Interpersonal Risk Factors for Sexual Aggression

This study conducted an up-to-date assessment of situational and interpersonal risk factors for sexual aggression. Two hundred undergraduate women from a medium sized college on the US west coast completed the Sexual Experiences Survey (SES) and a questionnaire developed by the authors. Participants who reported sexual victimization on the SES answered a series of questions about their most severe experience, as well as a representative, nonaggressive date. Participants who reported no sexual victimization answered questions only about a representative date. Risk factors were identified by comparing victimized participants’ sexually aggressive dates to nonvictimized participants’ dates, and victimized participants’ non-sexually aggressive dates to nonvictimized participants’ dates. Results revealed distinct situational and interpersonal differences between sexually aggressive and nonaggressive social interactions.     

Aggressive rejected children: Implications for school psychologists

By a sociometric rating procedure, 32 third-grade and 32 firth-grade boys were classified as peer-rejected. Standardized teacher ratings were completed for all rejected children in order to identify those children who also exhibited clinically significant levels of aggression. A significant portion of the rejected sample at each grade were rated as highly aggressive (t score≥65). Among third graders, however, 69% of the rejected group were classified as aggressive, but only 41% of the fifth graders were similarly classified. The aggressive rejected groups at both grade levels were also rated as exhibiting lower achievement motivation and higher levels of hostile withdrawal than their nonaggressive rejected counterparts. At the fifth-grade level, nonaggressive rejected children were rated as more anxious than aggressive children. Implications for both the identification and treatment of these children are discussed.     

The Role of Relational Aggression in Identifying Aggressive Boys and Girls

Peer perceptions of relational and overt aggression and peer evaluations of social competencies were obtained for 461 boys and 443 girls in second and third grades. In contrast to Crick and Grotpeter (1995), boys obtained higher relational and overt aggression scores than girls, and the relation between both types of aggression and peer evaluations were similar for boys and girls. When controlling for levels of overt aggression, relational aggression made a statistically significant but small contribution to the prediction of both peer-evaluated competencies and teacher ratings of aggression in boys and girls. Analyses treating relational and overt aggression as categorical variables revealed gender differences in the prevalence and corresponding sociometric status of aggressive subtypes. When peer-rated relational aggression status is not considered, 60% of aggressive girls, compared to 7% of aggressive boys, are not identified as aggressive. High levels of overt aggression were more likely to result in peer rejection for girls than for boys. In a subsample of 112 children, peer-rated relational aggression contributed more to the discrimination of teacher-identified aggressive and nonaggressive girls, whereas peer-rated overt aggression contributed more to the discrimination of teacher-identified aggressive and nonaggressive boys.     

Concurrent and predictive validity of self-reported aggressiveness

The subjects (60 boys) were drawn from the sample of a longitudinal study of social development and represented extremely aggressive, anxious, constructive, and submissive behaviour at the age of 8. They were presented with three question series concerning (1) their responses to aggressive attacks; (2) reactions in frustration situations presented in short stories; and (3) their aggressive initiatives. In each series the type of aggressive behaviour, attacker, victim, and other situational factors were systematically varied. In series 2 the type of response, open-ended or forced-choice, was also varied. The results showed that the most valid way of studying boys' self-observations on their aggressive behaviour was to ask if they attack somebody without a specific reason (series 3). This correlated with contemporaneous overt aggression at the age of 8 and predicted aggressiveness and various characteristics of antisocial aggressive development at the ages of 14 and 19. Self-observations on one's physical aggression were more valid for ratings of overt aggressiveness than on verbal aggression. The open-ended or forced-choice type of response did not affect the validity of aggressive responses. Of the categories of nonaggression, ‘conciliatory responses’ had the highest concurrent and predictive validity for constructiveness and other indicators of strong self-control.     

ESCAPE AS A FACTOR IN THE AGGRESSIVE BEHAVIOR OF TWO RETARDED CHILDREN

This study sought to identify some of the variables controlling the severely aggressive behavior of two retarded children. In Experiment 1, each child was presented with several demand and nondemand situations. Aggression was frequent in the demand situations and rare in the nondemand situations. When a stimulus correlated with the termination of demands was introduced, aggression fell to a near zero level. In Experiment 2, for one child, a variety of preferred reinforcers was introduced into the demand situation contingent on correct responding. Aggression abruptly decreased to a low level. Experiments 3 and 4 involved the second child. In Experiment 3, this child was permitted, in one condition, to leave the demand situation if he emitted a nonaggressive response. Aggression decreased to a low level. In Experiment 4, he was prevented, in one condition, from leaving the demand situation in spite of high levels of aggression. Aggression fell to a near zero level. In Experiments 3 and 4, he was permitted, in several conditions, to leave the demand situation following aggressive behavior. Aggression increased to a high level. The results suggested that: (1) aggression can sometimes function as an escape response; and (2) escape-motivated aggression can be controlled by: (a) introducing strongly preferred reinforcers to attenuate the aversiveness of the demand situation; (b) strengthening an alternative, nonaggressive escape response; or (c) using an escape-extinction procedure.     

Did the instigator intend to provoke? A key moderator in the relation between trait aggression and aggressive behavior

The purpose of this study was to investigate the cross‐situational consistency of trait aggression in provoking situations where an instigator (1) clearly intended to provoke, (2) clearly intended not to provoke, or (3) where presence of intention was ambiguous. It was hypothesized that cross‐situational consistency would be substantial, and that trait aggression would have the greatest impact on aggressive behavior in ambiguous situations. Participants were 80 female and 38 male undergraduate students. They completed the Aggression Questionnaire [Buss and Perry, J Pers Soc Psychol, 1992, pp. 452], read a set of 24 vignettes depicting conflict situations and rated their perceived likelihood of becoming angry and aggressive in those situations. An overall cross‐situational consistency correlation coefficient of r=.47 was found. It was also found that trait aggression had a significantly greater effect on the likelihood of aggressive responses in the ambiguous and intentional situations than it did in the unintentional situations. These results are discussed in relation to trait activation and hostile attribution bias. Aggr. Behav. 30:409–424, 2004. © 2004 Wiley‐Liss, Inc.     

Generalization of aggressive behavior in adolescent delinquent boys

The generalization of conditioned aggressive and nonaggressive responses in a group of six adolescent delinquent boys was investigated. Responses were reinforced in card games where a token reinforcement system with money as a back-up rinforcer was used. Conditioning of responses was rapid. Generalization, measured in terms of frequency of physical contact, was tested in a group game for which no reinforcement was given. Generalization occurred during aggressive contingencies. During nonaggressive contingencies, responses did not return completely to the baseline level.     

Attention and social problem solving as correlates of aggression in preschool males

This study examined the relationship between two cognitive processing variables-attention and social problem solving-and aggression in preschoolage boys. The 43 participants were administered two selective attention tasks that assess children's tendency to focus on aggressive versus cooperative social situations, the Preschool Interpersonal Problem Solving Test developed by Shure and Spivack, and the information and block design subtests of the Wechsler Preschool and Primary Scale of Intelligence. Aggressive behavior was measured by teacher ratings and observational data. Results indicated that, in contrast to their nonaggressive peers, aggressive preschool boys tend to focus their attention on aggressive social interactions in their environment. They also provide aggressive solutions to hypothetical interpersonal conflict situations more often than their less aggressive peers. Intelligence does not appear to play a mediating role in these relationships. Implications of these results for understanding and remediating aggressive behavior in young boys are discussed.This study is based upon data collected as part of the author's doctoral dissertation submitted to the Institute of Child Development, University of Minnesota. It was supported, in part, by a Bush Fellowship from the University of Minnesota. I would like to thank the parents, teachers, and children of the New Life Day Care and Joyce Child Care Centers in Minneapolis, and the Jack and Jill Preschool and Children's Home Society Day Care in St. Paul for their cooperation. I would also like to thank Judith List, Michael Reiner, and David Michell for help in stimulus preparation; Sally Westby, Andrea Easter, and Allyson Pearling for help with data collection; and W. Andrew Collins and Daniel Keating for their assistance throughout the study.     

Emotional catharsis and aggression revisited: heart rate reduction following aggressive responding

The authors tested two components of the catharsis theory of aggression: physiological tension reduction and aggressive drive reduction. On the basis of work in the stress-aggression literature, they also examined the moderating effect of impersonal stress exposure on cathartic reductions in heart rate following aggressive responding. Participants were instructed to administer nonaggressive (correct button) or aggressive (shock button) responses to a frustrating confederate in a laboratory aggression paradigm, and half the participants were exposed to an impersonal stressor (aversive air blasts) during the procedure. Heart rate was recorded before and after the participants administered the aggressive or nonaggressive response. Analyses revealed that participants exhibited reductions in heart rate following aggressive but not nonaggressive responding, but this was the case only for those not exposed to the impersonal stressor. Heart rate reductions during the experimental blocks actually predicted the most intense aggression in a subsequent block of trials. The results are considered in light of different theories of aggression by J. E. Hokanson (1974) and L. Berkowitz (1990) and have implications for interventions with anger-prone individuals.     

Attributional styles of aggressive boys and their mothers

To determine if mothers of aggressive boys have the same propensity as their sons to infer hostile intentions in ambiguous interpersonal situations, 50 mothers of aggressive and nonaggressive boys were each asked to interpret hypothetical situations involving themselves with their child, their partner, and a peer as well as hypothetical situations involving their child in interaction with classmates and teachers. Their sons also were each requested to interpret hypothetical situations involving themselves with their mother, a teacher, and a classmate. The results indicated that mothers of aggressive boys do share the propensity to infer hostility in ambiguous situations and may, in effect, model a hostile attributional bias. Mothers of aggressive boys failed to differentiate ambiguous from hostile situations and were as likely to infer hostile intentions in ambiguous as in hostile situations. The results also suggest a generalized tendency on the part of mothers of aggressive boys to infer negative motives and/or dispositions when accounting for the noxious behavior of their sons. Further, for the aggressive boys, the hostile attributional bias was evident with both peers and teachers. The presence of a hostile attribution was predictive of an aggressive response for the aggressive boys. Even in the face of clearly hostile, provocative behavior, nonaggressive boys were less likely to offer aggressive solutions than aggressive boys.The authors acknowledge the contribution of the staff from the Division of Child and Adolescent Psychiatry and Emergency Medicine, Department of Pediatrics, Emory University School of Medicine, and Grady Health Systems for their assistance and support in conducting this study.     

The Missouri Children's Picture Series: Correlates of the aggression scale in normal fourth-grade males

Missouri Children's Picture Series (MCPS) Aggression scale scores and four more traditional measures of aggression were intercorrelated for 40 normal fourthgrade boys. Results indicated that the MCPS Aggression scale must be viewed as a highly specific instrument which has little if any usefulness in a public school setting. In addition, the failure of the five aggression measures to be interrelated significantly suggests that aggression may be a highly situational response, with children varying in the modality through which they are able to express aggressive feelings and motives.     

Attributional biases in aggressive children and their mothers

To investigate if mothers and their aggressive children share the tendency to infer hostile motives from others' behavior in ambiguous social situations, 100 pairs of mothers and their clinic-referred or comparison children (50 boys and 50 girls) were asked to interpret hypothetical situations involving both overtly and relationally provocative scenarios. Results replicated previous findings of studies on social information processing of aggressive children and extended the findings to mothers of aggressive children. Findings were generally consistent with the hypothesis that mothers of aggressive children tend to view others' ambiguous actions as hostile, increasing the probability of responding with aggression and, in effect, modeling a hostile attributional bias for their children. Examinations of mothers' and their children's attributional and behavioral intentions suggested that mothers' and daughters' attributions and behavioral intentions were significantly correlated, whereas mothers' and sons' were not. Gender effects with regard to provocation type are also discussed.     

Social-information-processing factors in reactive and proactive aggression in children's peer groups

We examined social-information-processing mechanisms (e.g., hostile attributional biases and intention-cue detection deficits) in chronic reactive and proactive aggressive behavior in children's peer groups. In Study 1, a teacher-rating instrument was developed to assess these behaviors in elementary school children (N = 259). Reactive and proactive scales were found to be internally consistent, and factor analyses partially supported convergent and discriminant validities. In Study 2, behavioral correlates of these forms of aggression were examined through assessments by peers (N = 339). Both types of aggression related to social rejection, but only proactively aggressive boys were also viewed as leaders and as having a sense of humor. In Study 3, we hypothesized that reactive aggression (but not proactive aggression) would occur as a function of hostile attributional biases and intention-cue detection deficits. Four groups of socially rejected boys (reactive aggressive, proactive aggressive, reactive-proactive aggressive, and nonaggressive) and a group of average boys were presented with a series of hypothetical videorecorded vignettes depicting provocations by peers and were asked to interpret the intentions of the provocateur (N = 117). Only the two reactive-aggressive groups displayed biases and deficits in interpretations. In Study 4, attributional biases and deficits were found to be positively correlated with the rate of reactive aggression (but not proactive aggression) displayed in free play with peers (N = 127). These studies supported the hypothesis that attributional biases and deficits are related to reactive aggression but not to proactive aggression.     

Depression and Self-Esteem in Boys with Attention-Deficit/Hyperactivity Disorder: Associations with Comorbid Aggression and Explanatory Attributional Mechanisms

It was tested whether boys with attention-deficit/hyperactivity disorder (ADHD), subgrouped by aggressive status, would show higher rates of depressive symptomatology and lower levels of self-esteem than would comparison boys and, in a subsample, explored attributional mechanisms that may be related to such internalizing features. Study 1 utilized 114 boys with ADHD (all prior recipients of stimulant medication) and 87 comparison boys, aged 7–12 years. Aggressive boys with ADHD reported more symptoms of depression than did nonaggressive boys with ADHD, who, in turn, reported more depression than did comparison boys. Effect sizes were moderate to large and did not vary with a depression rating scale uncontaminated by ADHD-related items. For self-esteem, the most pronounced effect was that aggressive boys with ADHD showed lower levels than did nonaggressive ADHD or comparison boys; effects were again moderate to large. Study 2 participants were a subsample of boys with ADHD from Study 1 (N = 27). We probed causal attributions in ADHD-related domains through responses to hypothetical vignettes, in which the protagonist's medication status (medicated, not medicated) was crossed with type of outcome (good, bad). Medication-related attributions were frequent. In describing the protagonist's success in relation to medication treatment, the sample showed significant associations between (a) medication-related attributions and (b) increased depressive symptomatology as well as decreased self-esteem. We discuss attributional processes that may help to explain the variation in internalizing symptoms among children with ADHD.