





































RUNNING HEAD: RELATIONAL AND PHYSICAL AGGRESSION


Graduate Student Journal of Psychology                                                                             Copyright 2004 by the Department of Counseling & Clinical Psychology  
2004, Vol. 6                                                                                                                          Teachers College, Columbia University                          ISSN 1088-4661 
 
 

 

Relational Versus Physical Aggression: An Overview 
 

Debra Henninger 
Fordham University 

 
There is much neurological and cognitive research contributing  to explanations of physically ag-
gressive behavior. The brain’s activity and functioning are significant in the determination of rea-
sons 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 ag-
gression. 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 possi-
ble similarities. This review focuses primarily on neurological differences and cognitive deficits.    

 
 

individuals may be at high risk for numerous adjustment 
difficulties including feelings of rejection, loneliness, de-
pression, and isolation (Crick & Grotpeter, 1995). A rela-
tionally aggressive individual might have difficulties with 
peer relations, and over time might lose friends, miss out on 
opportunities, and develop low self-esteem. The lack of a 
support system and deteriorating feelings of self-worth can 
easily heighten the risk of depression, anxiety-related is-
sues, or even a personality disorder.   

Much of the research on aggression deals with neuro-
logical components as contributing factors (Lyvers, M., 
2000; Pihl, R. O., & Peterson, J. B., 1993; Raine, A., 2002; 
Seguin, J. R., Pihl, R. O., Harden, P. W., Tremblay, R. E., 
& Boulerice, B., 1995; Spoont, M. R., 1992), and mainly 
focuses on violent behavior or overt aggression. There is 
much less research regarding another form of aggression 
called relational aggression. In fact, there is little or no in-
formation on neurological components of relational aggres-
sion. It is because of this gap in the literature that this paper 
focuses on relational aggression and it is because both 
forms of aggression have the same intention – namely, to 
cause harm - that this paper addresses potential similarities 
between the two. The goal is to compare physical aggres-
sion and relational aggression in an attempt to share insight 
on a neurological and cognitive basis for future research on 
relational aggression.  

Crick (1996) found that relational aggression  is stable 
over time and is predictive of future social maladjustment. 
If this behavior is stable over time, the individual is not 
forming new patterns of behavior, and may be at risk for 
future behavior problems. It could be that the relationally 
aggressive individuals are not aware that their behavior is 
causing any aversive reactions, which would suggest possi-
ble cognitive impairments. Also, in a sample of girls, Crick 
found negative changes in adjustment as the behavior per-
sisted, meaning that the relationally aggressive individuals 
became more rejected by peers over time. This confounds 
the issue because, if social relationships are considered im-
portant to an individual, than the individual should notice 
when the relationships are faltering, and adjust their behav-
iors accordingly. Since relational aggression appears to be 
stable over time, it is as if these individuals are either not 
concerned with social relationships, or they lack the cogni-
tive abilities, such as an executive functioning or problem 
solving ability, to both be aware of the rejection of their 
peers, and/ or change their behavior patterns.  

 
Relational Aggression 

 
Relational aggression is an attempt to “harm others 

through purposeful manipulation or damage to their peer 
relationships (e.g., using social exclusion as a form of re-
taliation)” (Crick, 1996,). And so, relational aggression 
deals mainly with social issues and damage related to inter-
personal relationships. This form of aggression can be just 
as destructive to an individual as overt aggression, particu-
larly when one puts a great emphasis on their social interac-
tions and relationships. Since the intention is to inflict harm 
on another, and is purposefully chosen to inflict the most 
damaging kind of harm, relational aggression is just as seri-
ous an issue as overt aggression.  

Clinical and research literature highlights frequent 
cases of impairments in executive functioning and problem 
solving ability in physically aggressive individuals. These 
impairments usually involve the frontal regions of the brain. 
The following sections address the neurological and cogni-
tive components of physical aggression, and suggestions are 
made for potential similarities with relational aggression. 

Research suggests that relationally aggressive  
 
 
Correspondence concerning this article should be addressed to 
Debra Henninger, Department of Psychology, Fordham Univer-
sity, 441 East Forham Road, Bronx, NY  10458. E-mail: 
debra_henninger@yahoo.com 

 
 

13 



HENNINGER 
 

Neurological Contributions to Aggression 
 

In general, damage to the frontal lobe of the brain has 
been shown to result in a disruption of “aspects of auton-
omy, (such as) self-control, delay of gratification, drive 
inhibition, and the anticipation of future consequences, as 
well as selective attention and certain kinds of abstract 
problem-solving” (Lyvers 2000,). Research has also shown 
that limits in one’s problem solving abilities in social situa-
tions leads to physically aggressive behavior. A possible 
explanation for aggressive behavior is that individuals that 
are violently aggressive tend to use aggressive behavior in 
adverse conditions because they lack appropriate problem 
solving abilities (Spoont, M. R., 1992). Raine (2002) sug-
gests that damage to the prefrontal cortex results in the in-
ability to use reasoning skills adequately and difficulties 
making appropriate decisions, which contributes to behav-
iors such as impulsivity, recklessness, and irresponsibility. 
Also,  

“the prefrontal cortex is part of a neural circuit that 
plays a central role in fear conditioning and stress 
responsivity… and individuals who are less 
autonomically responsive to aversive stimuli… 
would be less susceptible to socializing punish-
ments, and hence become predisposed to antisocial 
behavior” (Raine, 2002).  
It is also thought that the prefrontal cortex regulates 

arousal and since there are deficits in arousal in aggressive 
individuals, they try to compensate by acting in a stimula-
tion-seeking behavior (e.g. aggression, impulsivity, etc.). 
All of these findings suggest one’s ability to solve problems 
and deal with social situations contributes to their behavior. 
Because individuals who exhibit physically aggressive be-
havior appear to be deficient in these abilities, they behave 
in an aggressive manner.  

Interestingly, “damage to areas of the prefrontal cortex 
reduces inhibitions and self-concern, causing an indiffer-
ence to the consequences to one’s behavior. Thus, areas of 
the prefrontal cortex are thought to modulate social skills” 
(Fishbein, 2000). Also, damage to the prefrontal cortex is 
related to posttraumatic violent behavior (Fishbein, 2000) 
and people with this damage “often exhibit impairments in 
ability to make rational decisions in personal and social 
matters, in addition to difficulties in the processing of emo-
tion” (Fishbein, 2000). Not only are people shown to be-
have in a more violent manner, but their ability to make 
decisions is impaired, which suggests they are thinking dif-
ferently about violence and the repercussions involved and 
their mental processes are lacking. This is all due to an al-
teration in the brain, specifically the prefrontal cortex, 
which indicates there is a distinct cognitive change.  

Furthermore,  
“impaired executive cognitive functioning (ECF) 
compromises the ability to interpret social cues 
during interpersonal interactions, which may lead 
to misperceptions of threat or hostility in conflict 
situations. ECF impairment may further undermine 

the ability to generate alternative socially adaptive 
behavioral responses and to execute a sequence of 
responses necessary to avoid aggressive or stressful 
interactions” (Fishbein, 2000).  

And so, when an individual perceives something or some-
one as a threat, they are more likely to react violently if 
they are ECF impaired. These functions are different from a 
nonviolent person and the differences result in a misinter-
pretation of intentions being threatening, which leads to 
violent defensive actions. “Particular regions of the prefron-
tal cortex (e.g. the orbitofrontal region) appear to play a role 
in forethought, behavioral inhibition, and capacity to learn 
from experience” (Fishbein, 2000). If violent individuals 
are not able to experience the same levels of forethought 
and learning from experience than nonviolent individuals, 
then they are not cognitively processing information the 
same way a nonviolent person would. Furthermore, “there 
is recent speculation that a poor connection between func-
tions of the prefrontal cortex and structures within the lim-
bic system may be responsible for disinhibited behavior, 
inability to act on an assessment of costs versus benefits, 
and poor emotional regulation” (Fishbein, 2000). These are 
biological differences in individuals that affect cognition 
which indicate not only a better understanding of why they 
behave the way they do, but an idea that the root of this 
behavior lies in the structures of the brain. Since relation-
ally aggressive individuals would need higher level social 
skills to manipulate social situations, it is possible that 
when they perceive someone as a threat, they do not react 
with physical violence, but emotional violence. Conflict 
situations are still instigating an aggressive behavior, albeit 
a non-physical form of aggressive behavior.  

Physically aggressive behavior also appears to be 
linked to the limbic system in the forebrain, which holds the 
hypothalamus and amygdala. Stimulation of the hypo-
thalamus or amygdala has been shown to lead to aggressive 
behavior (Clemente, C. D. & Chase, M. H., 1973). Za-
grodzka, Hedberg, Mann, and Morrison (1998) emphasized 
the role of the amygdala with aggressive behavior by look-
ing at cats with and without lesions in their amygdala. The 
cats were observed both while awake and during rapid eye 
movement (REM) sleep. In either state, the cats  did not 
display any aggressive behavior, but when the cats were 
exposed to aggression provoking situations, the cats with 
amygdalic lesions did not act aggressively. Also, the cats 
with lesions did not show normal predatory tendencies 
when mice were placed in their environment. The results 
show that the amygdala may play a role in aggressive be-
havior and dysfunction or deficit in this area leads to a lack 
of aggressive behavior.  

Glucocorticoid hypofunction or glucocorticoid plasma 
levels are also associated with physically aggressive behav-
ior. Halasz, Liposits, Kruk, and Haller (2002) used c-Fos 
protein immunocytochemistry to study the effects of im-
planting low-release glucocortoid pellets into rats. When 
the rats were exposed to an intruder, the level of c-Fos acti-
vation was induced in the brain areas related to aggression, 

14 



RELATIONAL AND PHYSICAL AGGRESSION 
 

including the amygdala and hypothalamus. When glucocor-
toid hypofunction was induced, there was an increase in 
attacks, especially to vulnerable parts of the intruder, and 
there was a dramatic increase in the activation of brain cen-
ters involved with stress response such as the hypothalamus 
and fear reactions such as theamygdala. Thus, glucocortoid 
hypofunction is related to stress sensitivity and fear and 
leads to physically aggressive behavior.  

Further examination of the amygdala’s role in aggres-
sive behavior leads to consideration of the neurotransmitter 
serotonin. Serotonin is regulated through the work of the 
forebrain, an area important in executive functioning.  This 
suggests that serotonin levels influence a threshold function 
in information processing and behavioral reactions. There-
fore, physically aggressive behavior may be linked to limits 
in problem solving abilities in social situations because of 
the influence of serotonin’s regulation from the forebrain. 
Serotonin regulates chemical processes in the brain, such as 
response to pain, body rhythms, and sexual behavior. Re-
duced serotonin levels are associated with heightened ag-
gression, and higher levels of serotonin are associated with 
reduced aggression in animals (Higley 1992; Popova 1991). 
In humans, “reduced brain serotonin function is associated 
with heightened vulnerability to depression, increased risk 
of violent suicide, propensity to exhibit aggressive or im-
pulsive behavior, and susceptibility to alcohol abuse both 
among persons with psychiatric disorders and among the 
general public” (Phil, R. O. & Peterson, J. B., 1993). 

Brain imaging has shown violent offenders have func-
tional deficits in anterior regions of the brain, particularly in 
the frontal region. (Raine, 2002). Explanations for the defi-
cits include reduced glucose in the frontal cortex, reduced 
frontal regional cerebral blood flow, and lower prefrontal 
concentrations of N-acetyl asparate and creatine phospho-
creatine (Raine,2002). Interestingly, individuals who have 
received damage to the prefrontal region of the brain “pro-
ceed to acquire an antisocial, psychopathic-like personality. 
These patients also show autonomic arousal and attention 
deficits to socially meaningful events” (Raine, 2002).   

In general, the structures of the brain most often asso-
ciated with physical aggression are in the frontal regions. 
These structures appear to be related to self-control, prob-
lem solving behavior, inhibition, and aggression. If the 
same issues of executive functioning and problem solving 
ability apply with regards to relationally aggressive indi-
viduals, the same regions of the brain would be important 
focal points of future research.  

 
Cognitive Contributions to Aggression 

 
Impairment in executive functioning is related to 

physically aggressive behavior. A study by Seguin, Pihl, 
Harden, Trembley, and Boulerice (1995) investigated the 
relationship between cognitive deficits and physical aggres-
sion. They looked at four factors: verbal learning, incidental 
spatial learning, tactile-lateral ability, and executive func-
tions. The results showed that the aggressive boys had diffi-

culties in executive functions, but not the other factors. Ex-
ecutive functions were defined as:  

“capacities for the initiation and maintenance of 
efficient attainment of goals. They are typically 
derived from tests that assess primarily 
programming and planning of goal-oriented motor 
behavior skills, modulation of behavior in light of 
expected future consequences, anticipation of 
events in the regulation of behavior, learning of 
contingency rules and the ability to use feedback 
cues, inhibition of response set and flexibility (vs. 
perseveration), abstract reasoning, problem 
solving, sustained attention, and concentration” 
(Seguin, et al., 1995).  

This explanation of executive functioning encompasses a 
wide range of abilities, and relational aggression can be 
attributed to the same abilities. As discussed previously, 
relationally aggressive individuals did not change their be-
havior over time even when rejected by peers. This relates 
to an apparent deficit in executive functioning in that be-
havior is not altered or modified in the apperent absence or 
ineffectiveness of feedback cues.  

Problem solving ability is associated with physically 
aggressive behavior. A longitudinal study by Seguin, Phil, 
Harden, Tremblay, & Boulerice (1995) found that cognitive 
executive functions were poor on performance among 
physically aggressive males. In the words of Seguin et al: 

 “Poor performance on several verbal abilities, 
such as reasoning, planning, and problem solving 
in the verbal modality (which are associated with 
antisocial behavior), theoretically rely as much on 
executive abilities as nonverbal executive tests… 
the executive functions tests used in the present 
study required active formation of representations 
in working memory that needed to be temporarily 
stored, accessible, and free of interference as they 
were continually monitored and scanned according 
to goals and rules” (Seguin et al., 1995). 
If an individual has difficulty using these cognitive 

functions, they are more likely to exhibit physically aggres-
sive behavior. This suggests  

“an association between history of aggressive be-
havior and impairment in executive functions most 
probably reflects an inability to organize several 
parameters simultaneously, uncover complex rules, 
anticipate consequences of choices and actions, and 
reflect abstractly (verbally or otherwise) in order to 
solve interpersonal and social problems. The ca-
pacity to reflect in impaired individuals may 
quickly be overwhelmed or their abilities poorly 
activated when they are in a motivational situation 
that calls for a more adaptive social response” (Se-
guin et al., 1995).  
Therefore, the tendency to exhibit aggressive behavior 

may be a result of a lack of ability to use cognitive proc-
esses such as working memory or reasoning skills. The ex-
ecutive functions may be hard to access or use because of 

15 



HENNINGER 
 

hitting or punching anyone (obviously explicit signs of 
harmful agression), the aggressor and others might not per-
ceive the behavior as being problematic.    

obstructions of these functions or they may be overloaded 
easily. The working memory of these individuals may not 
be as large or smooth as non-aggressive people, which 
would make it harder for them to organize their thinking 
and formulate and understand the best action to take.  

In support of this point, a study by Shahinfar, Ku-
persmidt, & Matza (2001) focused on social-cognitive and 
social information processing. Individuals that were victims 
of severe violence had significant levels of the measures of 
social information processing, including approval of ag-
gression, hostile attributional bias, and social goals; wit-
nesses to violence were more likely to perceive a positive 
outcome from violence (Shahinfar et al., 2001). A possible 
explanation is  

Relational aggressive individuals may also have diffi-
culty with problem solving abilities because of their inabil-
ity to resolve a conflict in a non-aggressive way (i.e. talking 
about a problem and proactively expressing their feelings or 
dismissing the conflict). Their ability to use reasoning skills 
might also be lacking due to a personal conflict that may or 
may not actually exist. Sometimes the relational aggressors 
simply perceive conflict when it is not actually there.  “that having been a victim of violence enhances 

children’s perceptions of threat in the world, 
which affects appraisal of the social environment 
and the interpretation of the behavior of others. 
Having been a victim of severe violence may 
also accentuate the need for revenge and domi-
nance of others as a response to one’s own ex-
perience” (Shafinfar et al., 2001).  

In a different light, problem solving skills and informa-
tion processing might alter the way an individual views 
behavior. A study by Slaby and Guerra (1988) selected ado-
lescents that were incarcerated in a maximum-security fa-
cility for having committed at least one violent criminal act 
and compared them with public high school adolescents. It 
was found that individuals with high levels of aggression 
also had low levels of problem solving skills and they gen-
erally felt that aggressiveness was a positive way to behave. 
This is thought to be somewhat related to information proc-
essing, although,  

The exposure to violence, whether it is as a victim or as a 
witness, appears to result in a particular form of cognitive 
thinking about violence in general. This relates to the phe-
nomenon of thinking that the world and other people are a 
threat, which was previously suggested to result from a 
biological difference in the brain, whereas Shanfinfar et al 
suggests this results from experience. And so, exposure to 
violence actually appears to change the way individuals 
think about violence.  

“it is unclear whether this hostile bias represents 
a deficit in processing information whereby ag-
gressive children merely assume that others’ in-
tentions would be similar to their own, presuma-
bly hostile, intentions, or whether this hostile 
bias reflects a more general set of “paranoid” be-
liefs about others’ motivations that might affect 
processing and interpretations of cues” (Slaby & 
Guerra, 1988).  

This mechanism may be the same for relationally ag-
gression individuals. If an individual is a victim of rela-
tional aggression, that individual might exhibit relationally 
aggressive behavior for revenge or because they might sim-
ply see the aggression as a way to get what they want.  This relates to cognition and how the aggressive individual 

is thinking and understanding information. There is a dif-
ference in the way these individuals are processing informa-
tion and it results in aggressive behavior. Slaby and Guerra 
illustrate how an individual “generates consequences”. 
Slaby and Guerra explain that “An individual must generate 
or draw from an existing repertoire of available responses. 
If he or she holds the belief, for instance, that heightened 
self-esteem is a consequence of aggression, this response 
might be available for consideration during the response-
evaluation step of information processing. However, this 
particular belief might also directly lead the individual to 
seek out opportunities to aggress” (Slaby & Guerra, 1988). 
It is possible that aggressive individuals have a limited cog-
nitive pool of responses and if those responses are all re-
lated to aggression, then they are bound to behave in an 
aggressive manner and furthermore, find situations to en-
gage in such behavior.  

Intelligence is also linked to violent behavior. A study 
by Sigurdsson, Gudjonsson, & Peersen (2001), adminis-
tered psychological tests to young juvenile offenders who 
had plead guilty to a criminal offense and then were given a 
conditional discharge. Sigurdsson et al  found that  

“as far as cognitive abilities were concerned the 
desisters (temporary or situational offending) 
scored significantly higher than the re-offenders 
(stable and persistent offenders) on the Standard 
Progressive Matrices and had better verbal mem-
ory recall on the GSS 1”.   

The Standard Progressive Matrices specifically measured 
intellectual ability, but does not translate to I.Q. scores. The 
individuals who continually committed violent offences had 
lower intelligence scores than the individuals who commit-
ted violent offences on a temporary or situational basis. 
This suggests that cognition affects whether or not an indi-
vidual will act in a violent manner. The results also suggest 
that low intellectual capacity may result in an inability to 
understand repercussions, socially acceptable behavior, or 
that these individuals are simply thinking on a different 
level that non-violent individuals.  

Relationally aggressive individuals might not realize 
their behavior is “wrong.”  A contrubiting factor of this 
may be that authority figures tend not to recognize relation-
ally aggressive behavior or punish individuals for it (Sim-
mons, 2002).  It  may  be  that  because the individual is not  

 

16 



RELATIONAL AND PHYSICAL AGGRESSION 
 

Conclusion 
 

Relational aggression and physical aggression are simi-
lar in that they both hold the same intention of inflicting 
harm on another person. Research on relational aggression 
mainly focuses on the social or peer relationship component 
of relational aggression. Little, if any, research has been 
done on the neurological contributions to relational aggres-
sion, which leaves this report to speculate on the similarities 
between neurological aspects involved with overt aggres-
sion and relational aggression. It is possible that individuals 
who exhibit relationally aggressive behaviors have neuro-
logically related deficits and/ or cognitive differences that 
contribute to this behavior.  

There are numerous contributions from the neurosci-
ence literature explaining aggressive behavior from a bio-
logical perspective. The brain and its activity and function-
ing are predominantly significant in the determination of 
reasons for aggressive behavior. An underlying theme sug-
gests the behavior is a result from limits in interpreting so-
cial situations adequately and lacking appropriate problem 
solving abilities. Since relationally aggressive behavior is 
stable over time and predictive of future social maladjust-
ment (Crick, 1996), impairments in executive functioning 
and problem solving skills are possible. Considering the 
social nature of relational aggression, these individuals 
probably have some of the same differences in brain activ-
ity and functioning as physically aggressive individuals.  

Future research should focus on neurological and cog-
nitive components of relationally aggressive behavior. Due 
to the breadth of information regarding these issues in 
physically aggressive individuals, and the underlying inten-
tion of harm that both forms of aggression share, compo-
nents related to physical aggression should be considered as 
a starting point to further understand relational aggression.  
 

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