Relational Versus Physical Aggression: an Overview

Relational Versus Physical Aggression: An Overview

Debra Henninger Fordham University

There is much neurological and cognitive research contributing to explanations of physically aggressive behavior. The brain’s activity and functioning are significant in the determination of reasons for this form of aggressive behavior. Relational aggression is another form of aggression, however, and most research in this area focuses on the social or peer relationship side of relational aggression. Little, if any, research has been done on the neurological contributions to relational aggression. Since relational aggression and overt aggression both hold the same intention of inflicting harm on another person, it is reasonable to compare these two forms of aggression and their possible similarities. This review focuses primarily on neurological differences and cognitive deficits.

Much of the research on aggression deals with neuro- individuals may be at high risk for numerous adjustment logical components as contributing factors (Lyvers, M., difficulties including feelings of rejection, loneliness, de- 2000; Pihl, R. O., & Peterson, J. B., 1993; Raine, A., 2002; pression, and isolation (Crick & Grotpeter, 1995). A rela- Seguin, J. R., Pihl, R. O., Harden, P. W., Tremblay, R. E., tionally aggressive individual might have difficulties with & Boulerice, B., 1995; Spoont, M. R., 1992), and mainly peer relations, and over time might lose friends, miss out on focuses on violent behavior or overt aggression. There is opportunities, and develop low self-esteem. The lack of a much less research regarding another form of aggression support system and deteriorating feelings of self-worth can called relational aggression. In fact, there is little or no in- easily heighten the risk of depression, anxiety-related is- formation on neurological components of relational aggres- sues, or even a personality disorder. sion. It is because of this gap in the literature that this paper Crick (1996) found that relational aggression is stable focuses on relational aggression and it is because both over time and is predictive of future social maladjustment. forms of aggression have the same intention – namely, to If this behavior is stable over time, the individual is not cause harm - that this paper addresses potential similarities forming new patterns of behavior, and may be at risk for between the two. The goal is to compare physical aggres- future behavior problems. It could be that the relationally sion and relational aggression in an attempt to share insight aggressive individuals are not aware that their behavior is on a neurological and cognitive basis for future research on causing any aversive reactions, which would suggest possi- relational aggression. ble cognitive impairments. Also, in a sample of girls, Crick found negative changes in adjustment as the behavior per- Relational Aggression sisted, meaning that the relationally aggressive individuals became more rejected by peers over time. This confounds Relational aggression is an attempt to “harm others the issue because, if social relationships are considered im- through purposeful manipulation or damage to their peer portant to an individual, than the individual should notice relationships (e.g., using social exclusion as a form of re- when the relationships are faltering, and adjust their behav- taliation)” (Crick, 1996,). And so, relational aggression iors accordingly. Since relational aggression appears to be deals mainly with social issues and damage related to inter- stable over time, it is as if these individuals are either not personal relationships. This form of aggression can be just concerned with social relationships, or they lack the cogni- as destructive to an individual as overt aggression, particu- tive abilities, such as an executive functioning or problem larly when one puts a great emphasis on their social interac- solving ability, to both be aware of the rejection of their tions and relationships. Since the intention is to inflict harm peers, and/ or change their behavior patterns. on another, and is purposefully chosen to inflict the most Clinical and research literature highlights frequent damaging kind of harm, relational aggression is just as seri- cases of impairments in executive functioning and problem ous an issue as overt aggression. solving ability in physically aggressive individuals. These Research suggests that relationally aggressive impairments usually involve the frontal regions of the brain. The following sections address the neurological and cognitive components of physical aggression, and suggestions are Correspondence concerning this article should be addressed to made for potential similarities with relational aggression. Debra Henninger, Department of Psychology, Fordham Univer- sity, 441 East Forham Road, Bronx, NY 10458. E-mail: [email protected]

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Neurological Contributions to Aggression the ability to generate alternative socially adaptive behavioral responses and to execute a sequence of In general, damage to the frontal lobe of the brain has responses necessary to avoid aggressive or stressful been shown to result in a disruption of “aspects of auton- interactions” (Fishbein, 2000). omy, (such as) self-control, delay of gratification, drive And so, when an individual perceives something or some- inhibition, and the anticipation of future consequences, as one as a threat, they are more likely to react violently if well as selective attention and certain kinds of abstract they are ECF impaired. These functions are different from a problem-solving” (Lyvers 2000,). Research has also shown nonviolent person and the differences result in a misinter- that limits in one’s problem solving abilities in social situa- pretation of intentions being threatening, which leads to tions leads to physically aggressive behavior. A possible violent defensive actions. “Particular regions of the prefron- explanation for aggressive behavior is that individuals that tal cortex (e.g. the orbitofrontal region) appear to play a role are violently aggressive tend to use aggressive behavior in in forethought, behavioral inhibition, and capacity to learn adverse conditions because they lack appropriate problem from experience” (Fishbein, 2000). If violent individuals solving abilities (Spoont, M. R., 1992). Raine (2002) sug- are not able to experience the same levels of forethought gests that damage to the prefrontal cortex results in the in- and learning from experience than nonviolent individuals, ability to use reasoning skills adequately and difficulties then they are not cognitively processing information the making appropriate decisions, which contributes to behav- same way a nonviolent person would. Furthermore, “there iors such as impulsivity, recklessness, and irresponsibility. is recent speculation that a poor connection between func- Also, tions of the prefrontal cortex and structures within the lim- “the prefrontal cortex is part of a neural circuit that bic system may be responsible for disinhibited behavior, plays a central role in fear conditioning and stress inability to act on an assessment of costs versus benefits, responsivity… and individuals who are less and poor emotional regulation” (Fishbein, 2000). These are autonomically responsive to aversive stimuli… biological differences in individuals that affect cognition would be less susceptible to socializing punish- which indicate not only a better understanding of why they ments, and hence become predisposed to antisocial behave the way they do, but an idea that the root of this behavior” (Raine, 2002). behavior lies in the structures of the brain. Since relation- It is also thought that the prefrontal cortex regulates ally aggressive individuals would need higher level social arousal and since there are deficits in arousal in aggressive skills to manipulate social situations, it is possible that individuals, they try to compensate by acting in a stimula- when they perceive someone as a threat, they do not react tion-seeking behavior (e.g. aggression, impulsivity, etc.). with physical violence, but emotional violence. Conflict All of these findings suggest one’s ability to solve problems situations are still instigating an aggressive behavior, albeit and deal with social situations contributes to their behavior. a non-physical form of aggressive behavior. Because individuals who exhibit physically aggressive be- Physically aggressive behavior also appears to be havior appear to be deficient in these abilities, they behave linked to the limbic system in the forebrain, which holds the in an aggressive manner. hypothalamus and amygdala. Stimulation of the hypo- Interestingly, “damage to areas of the prefrontal cortex thalamus or amygdala has been shown to lead to aggressive reduces inhibitions and self-concern, causing an indiffer- behavior (Clemente, C. D. & Chase, M. H., 1973). Za- ence to the consequences to one’s behavior. Thus, areas of grodzka, Hedberg, Mann, and Morrison (1998) emphasized the prefrontal cortex are thought to modulate social skills” the role of the amygdala with aggressive behavior by look- (Fishbein, 2000). Also, damage to the prefrontal cortex is ing at cats with and without lesions in their amygdala. The related to posttraumatic violent behavior (Fishbein, 2000) cats were observed both while awake and during rapid eye and people with this damage “often exhibit impairments in movement (REM) sleep. In either state, the cats did not ability to make rational decisions in personal and social display any aggressive behavior, but when the cats were matters, in addition to difficulties in the processing of emo- exposed to aggression provoking situations, the cats with tion” (Fishbein, 2000). Not only are people shown to be- amygdalic lesions did not act aggressively. Also, the cats have in a more violent manner, but their ability to make with lesions did not show normal predatory tendencies decisions is impaired, which suggests they are thinking dif- when mice were placed in their environment. The results ferently about violence and the repercussions involved and show that the amygdala may play a role in aggressive be- their mental processes are lacking. This is all due to an al- havior and dysfunction or deficit in this area leads to a lack teration in the brain, specifically the prefrontal cortex, of aggressive behavior. which indicates there is a distinct cognitive change. Glucocorticoid hypofunction or glucocorticoid plasma Furthermore, levels are also associated with physically aggressive behav- “impaired executive cognitive functioning (ECF) ior. Halasz, Liposits, Kruk, and Haller (2002) used c-Fos compromises the ability to interpret social cues protein immunocytochemistry to study the effects of im- during interpersonal interactions, which may lead planting low-release glucocortoid pellets into rats. When to misperceptions of threat or hostility in conflict the rats were exposed to an intruder, the level of c-Fos acti- situations. ECF impairment may further undermine vation was induced in the brain areas related to aggression,

14 RELATIONAL AND PHYSICAL AGGRESSION including the amygdala and hypothalamus. When glucocor- culties in executive functions, but not the other factors. Ex- toid hypofunction was induced, there was an increase in ecutive functions were defined as: attacks, especially to vulnerable parts of the intruder, and “capacities for the initiation and maintenance of there was a dramatic increase in the activation of brain cen- efficient attainment of goals. They are typically ters involved with stress response such as the hypothalamus derived from tests that assess primarily and fear reactions such as theamygdala. Thus, glucocortoid programming and planning of goal-oriented motor hypofunction is related to stress sensitivity and fear and behavior skills, modulation of behavior in light of leads to physically aggressive behavior. expected future consequences, anticipation of Further examination of the amygdala’s role in aggres- events in the regulation of behavior, learning of sive behavior leads to consideration of the neurotransmitter contingency rules and the ability to use feedback serotonin. Serotonin is regulated through the work of the cues, inhibition of response set and flexibility (vs. forebrain, an area important in executive functioning. This perseveration), abstract reasoning, problem suggests that serotonin levels influence a threshold function solving, sustained attention, and concentration” in information processing and behavioral reactions. There- (Seguin, et al., 1995). fore, physically aggressive behavior may be linked to limits This explanation of executive functioning encompasses a in problem solving abilities in social situations because of wide range of abilities, and relational aggression can be the influence of serotonin’s regulation from the forebrain. attributed to the same abilities. As discussed previously, Serotonin regulates chemical processes in the brain, such as relationally aggressive individuals did not change their be- response to pain, body rhythms, and sexual behavior. Re- havior over time even when rejected by peers. This relates duced serotonin levels are associated with heightened ag- to an apparent deficit in executive functioning in that be- gression, and higher levels of serotonin are associated with havior is not altered or modified in the apperent absence or reduced aggression in animals (Higley 1992; Popova 1991). ineffectiveness of feedback cues. In humans, “reduced brain serotonin function is associated Problem solving ability is associated with physically with heightened vulnerability to depression, increased risk aggressive behavior. A longitudinal study by Seguin, Phil, of violent suicide, propensity to exhibit aggressive or im- Harden, Tremblay, & Boulerice (1995) found that cognitive pulsive behavior, and susceptibility to alcohol abuse both executive functions were poor on performance among among persons with psychiatric disorders and among the physically aggressive males. In the words of Seguin et al: general public” (Phil, R. O. & Peterson, J. B., 1993). “Poor performance on several verbal abilities, Brain imaging has shown violent offenders have func- such as reasoning, planning, and problem solving tional deficits in anterior regions of the brain, particularly in in the verbal modality (which are associated with the frontal region. (Raine, 2002). Explanations for the defi- antisocial behavior), theoretically rely as much on cits include reduced glucose in the frontal cortex, reduced executive abilities as nonverbal executive tests… frontal regional cerebral blood flow, and lower prefrontal the executive functions tests used in the present concentrations of N-acetyl asparate and creatine phospho- study required active formation of representations creatine (Raine,2002). Interestingly, individuals who have in working memory that needed to be temporarily received damage to the prefrontal region of the brain “pro- stored, accessible, and free of interference as they ceed to acquire an antisocial, psychopathic-like personality. were continually monitored and scanned according These patients also show autonomic arousal and attention to goals and rules” (Seguin et al., 1995). deficits to socially meaningful events” (Raine, 2002). If an individual has difficulty using these cognitive In general, the structures of the brain most often asso- functions, they are more likely to exhibit physically aggres- ciated with physical aggression are in the frontal regions. sive behavior. This suggests These structures appear to be related to self-control, prob- “an association between history of aggressive be- lem solving behavior, inhibition, and aggression. If the havior and impairment in executive functions most same issues of executive functioning and problem solving probably reflects an inability to organize several ability apply with regards to relationally aggressive indi- parameters simultaneously, uncover complex rules, viduals, the same regions of the brain would be important anticipate consequences of choices and actions, and focal points of future research. reflect abstractly (verbally or otherwise) in order to solve interpersonal and social problems. The ca- Cognitive Contributions to Aggression pacity to reflect in impaired individuals may quickly be overwhelmed or their abilities poorly Impairment in executive functioning is related to activated when they are in a motivational situation physically aggressive behavior. A study by Seguin, Pihl, that calls for a more adaptive social response” (Se- Harden, Trembley, and Boulerice (1995) investigated the guin et al., 1995). relationship between cognitive deficits and physical aggres- Therefore, the tendency to exhibit aggressive behavior sion. They looked at four factors: verbal learning, incidental may be a result of a lack of ability to use cognitive proc- spatial learning, tactile-lateral ability, and executive func- esses such as working memory or reasoning skills. The ex- tions. The results showed that the aggressive boys had diffi- ecutive functions may be hard to access or use because of

15 HENNINGER obstructions of these functions or they may be overloaded hitting or punching anyone (obviously explicit signs of easily. The working memory of these individuals may not harmful agression), the aggressor and others might not per- be as large or smooth as non-aggressive people, which ceive the behavior as being problematic. would make it harder for them to organize their thinking In support of this point, a study by Shahinfar, Ku- and formulate and understand the best action to take. persmidt, & Matza (2001) focused on social-cognitive and Relational aggressive individuals may also have diffi- social information processing. Individuals that were victims culty with problem solving abilities because of their inabil- of severe violence had significant levels of the measures of ity to resolve a conflict in a non-aggressive way (i.e. talking social information processing, including approval of ag- about a problem and proactively expressing their feelings or gression, hostile attributional bias, and social goals; wit- dismissing the conflict). Their ability to use reasoning skills nesses to violence were more likely to perceive a positive might also be lacking due to a personal conflict that may or outcome from violence (Shahinfar et al., 2001). A possible may not actually exist. Sometimes the relational aggressors explanation is simply perceive conflict when it is not actually there. “that having been a victim of violence enhances In a different light, problem solving skills and informa- children’s perceptions of threat in the world, tion processing might alter the way an individual views which affects appraisal of the social environment behavior. A study by Slaby and Guerra (1988) selected ado- and the interpretation of the behavior of others. lescents that were incarcerated in a maximum-security fa- Having been a victim of severe violence may cility for having committed at least one violent criminal act also accentuate the need for revenge and domi- and compared them with public high school adolescents. It nance of others as a response to one’s own ex- was found that individuals with high levels of aggression perience” (Shafinfar et al., 2001). also had low levels of problem solving skills and they gen- The exposure to violence, whether it is as a victim or as a erally felt that aggressiveness was a positive way to behave. witness, appears to result in a particular form of cognitive This is thought to be somewhat related to information proc- thinking about violence in general. This relates to the phe- essing, although, nomenon of thinking that the world and other people are a “it is unclear whether this hostile bias represents threat, which was previously suggested to result from a a deficit in processing information whereby ag- biological difference in the brain, whereas Shanfinfar et al gressive children merely assume that others’ in- suggests this results from experience. And so, exposure to tentions would be similar to their own, presuma- violence actually appears to change the way individuals bly hostile, intentions, or whether this hostile think about violence. bias reflects a more general set of “paranoid” be- This mechanism may be the same for relationally ag- liefs about others’ motivations that might affect gression individuals. If an individual is a victim of rela- processing and interpretations of cues” (Slaby & tional aggression, that individual might exhibit relationally Guerra, 1988). aggressive behavior for revenge or because they might sim- This relates to cognition and how the aggressive individual ply see the aggression as a way to get what they want. is thinking and understanding information. There is a dif- Intelligence is also linked to violent behavior. A study ference in the way these individuals are processing informa- by Sigurdsson, Gudjonsson, & Peersen (2001), adminis- tion and it results in aggressive behavior. Slaby and Guerra tered psychological tests to young juvenile offenders who illustrate how an individual “generates consequences”. had plead guilty to a criminal offense and then were given a Slaby and Guerra explain that “An individual must generate conditional discharge. Sigurdsson et al found that or draw from an existing repertoire of available responses. “as far as cognitive abilities were concerned the If he or she holds the belief, for instance, that heightened desisters (temporary or situational offending) self-esteem is a consequence of aggression, this response scored significantly higher than the re-offenders might be available for consideration during the response- (stable and persistent offenders) on the Standard evaluation step of information processing. However, this Progressive Matrices and had better verbal mem- particular belief might also directly lead the individual to ory recall on the GSS 1”. seek out opportunities to aggress” (Slaby & Guerra, 1988). The Standard Progressive Matrices specifically measured It is possible that aggressive individuals have a limited cog- intellectual ability, but does not translate to I.Q. scores. The nitive pool of responses and if those responses are all re- individuals who continually committed violent offences had lated to aggression, then they are bound to behave in an lower intelligence scores than the individuals who commit- aggressive manner and furthermore, find situations to en- ted violent offences on a temporary or situational basis. gage in such behavior. This suggests that cognition affects whether or not an indi- Relationally aggressive individuals might not realize vidual will act in a violent manner. The results also suggest their behavior is “wrong.” A contrubiting factor of this that low intellectual capacity may result in an inability to may be that authority figures tend not to recognize relation- understand repercussions, socially acceptable behavior, or ally aggressive behavior or punish individuals for it (Sim- that these individuals are simply thinking on a different mons, 2002). It may be that because the individual is not level that non-violent individuals.

16 RELATIONAL AND PHYSICAL AGGRESSION

Conclusion abuse, and violence: A conceptual framework. Criminal Justice and Behavior, 27(2), 139-159. Relational aggression and physical aggression are simi- Halasz, J., Liposits, Z., Kruk, M. R., & Haller, J. (2002) lar in that they both hold the same intention of inflicting Neural background of glucocortoid dysfunction-induced harm on another person. Research on relational aggression abnormal aggression in rats: involvement of fear- and mainly focuses on the social or peer relationship component stress-related structures. European Journal of Neurosci- of relational aggression. Little, if any, research has been ence, 15. pp. 561-569. done on the neurological contributions to relational aggres- Higley, J. D., Mehlman, P. T., Taub, D. M., & Higley, S. B. sion, which leaves this report to speculate on the similarities (1992). Cerebrospinal fluid monoamine and adrenal cor- between neurological aspects involved with overt aggres- relates of aggression in free-ranging rhesus monkeys. Ar- sion and relational aggression. It is possible that individuals chives of General Psychiatry, 49 (6), pp. 436-441. who exhibit relationally aggressive behaviors have neuro- Lyvers, M. (2000) “Loss of control” in alcoholism and drug logically related deficits and/ or cognitive differences that addiction: A neuroscientific interpretation. Experimental contribute to this behavior. and Clinical Psychopharmacology, 8 (2), pp. 225-249. There are numerous contributions from the neurosci- Pihl, R. O., & Peterson, J. B. (1993). Alcohol, serotonin, ence literature explaining aggressive behavior from a bio- and aggression. Alcohol Health and Research World, 17 logical perspective. The brain and its activity and function- (2), pp. 113. ing are predominantly significant in the determination of Popova, N. K., Voitenko, N. N., Kulikov, A. V., & Av- reasons for aggressive behavior. An underlying theme sug- gustinovich, D. F. (1991). Evidence for the involvement gests the behavior is a result from limits in interpreting so- of central serotonin in mechanism of domestication of cial situations adequately and lacking appropriate problem silver foxes. Pharmacology, Biochemistry & Behavior, solving abilities. Since relationally aggressive behavior is 40 (4), pp. 751-756. stable over time and predictive of future social maladjust- Raine, A. (2002). Annotation: The role of prefrontal defi- ment (Crick, 1996), impairments in executive functioning cits, low autonomic arousal, and early health factors in and problem solving skills are possible. Considering the the development of antisocial and aggressive behavior in social nature of relational aggression, these individuals children. Journal of Child Psychology and Psychiatry probably have some of the same differences in brain activ- and Allied Disciplines, 43 (4), pp. 417-434. ity and functioning as physically aggressive individuals. Seguin, J. R., Pihl, R. O., Harden, P. W., Tremblay, R. E., Future research should focus on neurological and cog- & Boulerice, B. (1995). Cognitive and neuropsychologi- nitive components of relationally aggressive behavior. Due cal characteristics of physically aggressive boys. Journal to the breadth of information regarding these issues in of Abnormal Psychology, 104 (4), pp. 614-624. physically aggressive individuals, and the underlying inten- Shahinfar, A., Kupersmidt, J. B., & Matza, L. S. (2001). tion of harm that both forms of aggression share, compo- The relation between exposure to violence and social in- nents related to physical aggression should be considered as formation processing among incarcerated adolescents. a starting point to further understand relational aggression. Journal of Abnormal Psychology, 110(1), 136-141. Sigurdsson, J. F., Gudjonsson, G. H., & Peersen, M. (2001). References Implications for human psychopathology. 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