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Theories of Aggression

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Biology 202
1999 Final Web Reports
On Serendip

Theories of Aggression

Alexandra K. Smith

"Two Gunman at Colorado School Reportedly Kill Up to 23 Before Dying in a Siege." On Tuesday, April 20, 1999, two students, Eric Harris and Dylan Klebold, of Columbine High School, shocked the nation when they entered the school armed with guns and explosives, killing fellow students and a teacher before taking their own lives. Stories of random violence and aggression such as this all too often plague the media. While the attention of the nation has recently been focused on the Colorado slayings, history reveals countless other similar crimes of aggression targeted towards innocent individuals. In both Nazi Germany and the more recent Bosnia conflict, ethnic cleansing has been used to violently eliminate certain races. In the early 1990s, Timothy McVegh's vengeful intentions led him to use a car bomb to kill hundreds of innocent people in the explosion of the Oklahoma City Federal Building.

In these cases, the culprits were seemingly normal people that displaced their aggression on innocent bystanders for a variety of reasons. What is the cause of this unleashed aggression toward society? How can we come to explain such acts of aggression and violence? Are they a result of societal influences, or are some individuals biologically predisposed to crime? This paper attempts to analyze some of the prevailing theories of aggression. The theories can be classified into three groups: innate or biological theories, drive theories and social learning theories. In light of the evidence produced for each, it is my goal to formulate a conclusion about which particular theory seems most substantiated and reasonable.

Sigmund Freud is well known as the father of psychoanalysis. In his early theory, Freud asserts that human behaviors are motivated by sexual and instinctive drives known as the libido, which is energy derived from the Eros, or life instinct (1). Thus, the repression of such libidinal urges is displayed as aggression. As an example of the expression of aggression as explained by Freud, let us consider his work on childhood aggression, and the Oedipus Complex. A boy around age five begins to develop an intense sexual desire for his mother. He has come to regard her as the provider of food and love and thus wants to pursue an intimate, close relationship. The desire for his mother causes the boy to reject and display aggression toward his father. The father is viewed as a competitive rival and the goal they both try to attain is the mother's affection (1). Thus, an internal conflict arises in the young boy. On one hand, he loves his father, but on the other, he wants him to essentially "disappear", so that he can form an intimate relationship with his mother. A boy will develop an immense feeling of guilt over this tumultuous conflict and come to recognize the superiority of his father because of his size. This evokes fear in the boy and he will believe that by pursuing his mother's affection his father will want to hurt him, essentially castrate him (1). To resolve the conflict, the boy learns to reject his mother as a love object and will eventually identify with his father. Thus, he has come to understand that an intimate relationship with his mother is essentially inappropriate.

Freud also developed the female Oedipal Complex, later named the Electra Complex, which is a similar theory for the childhood aggression of girls. In this theory, a girl around the age of five develops penis envy in attempts to relate to her father and rejects her mother (2). A similar internal conflict arises in the young girl, which is resolved after regarding her father as an inappropriate love object and ultimately identifying with her mother.

These examples of Freud's psychoanalytic theory demonstrate the idea that aggression is an innate personality characteristic common to all humans, and that behavior is motivated by sexual drives (1). According to Freud and demonstrated by the male and female Oedipal Complexes, aggression in children is instinctual and should be resolved by adulthood. Therefore, over the course of development, after the child has rejected the opposite sex parent, he or she will enter a period of latency in which they commonly reject all boys or all girls. Once puberty is reached, attention shifts to the genital region as an area of pleasure (1). Freud asserted that once this stage is reached, both men and women would search for an appropriate member of the opposite sex to fulfill sexual urges (2). Thus, Freud states that in individuals where the childhood conflicts have been successfully resolved, all aggression has been removed by adulthood in the pattern of development.

Later, Freud added the concept of Thanatos, or death force, to his Eros theory of human behavior (3). Contrary to the libido energy emitted from the Eros, Thanatos energy encourages destruction and death. In this conflict between Eros and Thanatos, some of the negative energy of the Thanatos is directed toward others, to prevent the self-destruction of the individual (4). Thus, Freud claimed that the displacement of negative energy of the Thanatos onto others is the basis of aggression (5).

While Freud's adapted theory focused on the death instinct as the cause of aggression, Konrad Lorenz looked at instinctual aggressiveness as a product of evolution. In essence, Lorenz combined Freud's theory of aggression with Charles Darwin's natural selection theory. In this interpretation, aggressiveness is beneficial and allows for the survival and success of populations of aggressive species since the strongest animals would eliminate weaker ones and over the course of evolution, the result would be an ultimate stronger, healthier population (4). This evolutionary theory of aggression is one of many biological theories, which as a whole are similar to the psychoanalytic theory in that aggression is understood to be instinctual. Common to some of the other biological theories is the proposition that aggression is the manifestation of a genetic or chemical influence (6). Empirical evidence shows that cerebral electrical stimulation of certain locations can induce or inhibit aggression (4). Other biological theorists propose that genetics may be a component of aggression. Observational studies on certain animals show that some breeds are more aggressive while others are naturally passive (6). While it is yet scientifically undetermined, proponents of the genetic theory explain this presence or absence of aggression in particular breeds in terms of a single gene or interaction of genes that are currently being studied. Studies that are more complete have shown that the presence or absence of particular chemicals and hormones affects aggression. For example, high levels of the hormone testosterone and neurotransmitters such as serotonin, dopamine and noradrenalin produce higher levels of aggression in animals (7). In addition, serotonin has been used pharmacologically as an effective treatment in combating erratic aggression (6). While there is still vast research being conducted in the area of chemical and genetic manipulation in response to aggression management, biological theorists recognize that aggression is instinctive, yet feel as though direct medicinal measures can be taken to interfere with the underlying drive.

The third category of aggression is the drive theories, which attribute aggression to an impulse created by an innate need (6). The most well known drive theory of aggression is the frustration-aggression hypothesis proposed by a group of researchers at Yale led by John Dollard (3). In this theory, frustration and aggression are linked in a cause and effect relationship. Frustration is the cause of aggression and aggression is the result of frustration (5). The early empirical evidence for this theory involved the examination of prison populations. A variety of studies were conducted to determine age, economic status and intelligence of inmates and to relate these variables to the amount of frustration of each individual prisoner. The results showed that the higher the frustration level, the more prone the person was to act aggressively or commit crime (3). Other researches that have examined the frustration-aggression hypothesis have determined that frustration is only one source of aggression and that other contributing factors exist. A study done by Geen and Berkowitz in 1967 showed that frustration is merely a "weak instigator of aggression," and that the presence of other cues can elicit more aggressive behavior (3). Therefore, while frustration and aggression seem to be closely linked, the mere presence of frustration does not seem to suggest aggression. The frustration-aggression theory has therefore been modified to include other instigating factors of aggression including tension.

Finally, one of the most radical and well-documented approaches to aggression is the social learning theory, which, unlike the other models, does not attribute aggression to an internal mechanism. There are two important principles underlying this theory. In this hypothesis, aggression is initially learned from social behavior and it is maintained by other conditions (4). There are a variety of proposed methods through which aggression is learned and maintained. One method of learning aggressive behavior is through simple operant conditioning (4). If after performing an aggressive act an animal or human receives a positive reinforcement (such as food or a toy), they are likely to repeat the behavior in order to gain more rewards. In this way, the aggressive act becomes positively associated with the reward, which encourages the further display of aggression. Aggressive responses can also be acquired through social modeling or social referencing (6). Small children are likely to look to a familiar face to see how to react to a particular person or situation. By demonstrating aggression, one can unknowingly encourage aggression in suggestible children. One of the most popular current debates which centers around the idea that TV violence contributes to increased aggression in viewers exemplifies the idea that people are easily influenced by others' behavior. By modeling the behaviors of TV, movie or video game characters, acts of aggression become increasingly more frequent and violent. Researchers suggest that after aggressive behaviors are acquired, other factors serve to maintain their presence including self-reinforcement, in which the aggressive individual is proud of his or her harmful action (4). Other maintaining conditions are tangible and intangible rewards. Whether a person receives money or a medal for injuring or harming another, that person is more likely to commit aggressive acts in the future due to the reinforcement received. Studies have shown that many aspects of the social learning theory of aggression are highly demonstrable in and out of the laboratory and by both humans and animals (6). Currently one of the most popular theories of aggression, it seems as though the social learning theory competently describes the acquisition and maintenance of aggression and violence in a variety of subjects.

To formulate a conclusion about the theories of aggression I decided to analyze the existing empirical evidence in support of each, and examine their strengths and weaknesses. Freud's instinct theory of aggression is characteristic of most of his work, with psychic energy focused on the libido and the incessant motivation of sexual desires. While I give Freud credit for having developed such a profound theory very early in the history of social psychology, I cannot support his theory of aggression for two reasons. First, despite Freud's interest in childhood development and anxiety, he failed to observe children in his studies. His theories are substantially based on hypotheses. Second, there is no existing empirical evidence to support Freud's instinct theory of aggression. Thus, in my opinion, Freud's theory can be virtually discounted as a scientific theory of aggression as there is no credible, tangible support.

The biological theories of aggression have much to offer about the physical and neurobiological causes of aggressive acts. I find this theory intriguing because it follows my interest in pinpointing anatomical and neurochemical roots of behavior. However, there is only limited evidence as of yet in this area. I believe that we will continue to see accumulating empirical evidence for biological causes of aggression over the next decade or two as medical technology advances. In addition, the vastly developing field of genetics will in all likelihood pinpoint genetic sources of aggression as the Human Genome Project proceeds.

Finally, the social learning theory is the most well supported and documented theory of aggression. Not only is it widely applicable to men and women, girls and boys and members of all different age levels, but it also has been continually modified and developed over the past 40 years so as to incorporate new findings.

In my overall examination of aggression theories, it is important that I include one of the major findings that I learned from the neurobiology course. The history of science and especially neurobiology has taught us that one cannot examine a problem from just one angle. Doing so leads to narrow conclusions that are only applicable to particulars. In order to obtain a general, well-rounded view, one must study the problem from different scientific perspectives. Aggression cannot and should not be explained by just one of these theories in particular. Rather, by combining the strengths of all the aggression theories, one can obtain a general and dependable ideology. In order to dissect aggression and understand it fully, it is necessary to include the ideas of sexual energy, biological factors, frustration, and social influences and, most importantly, continue researching these respective areas. As a manifestation of the central nervous system, aggression is an output that can be caused by many things. As we have learned, behaviors can be generated by an external input, from within the nervous system, by intermediate factors or even by intrinsic variability. In conclusion, in today's violent world filled to capacity with murders and violence, we must regard aggression as a summated response to many factors. Individually, the factors probably are harmless, but when united, they can be unleashed as aggression in which case terrible crimes take the lives of so many innocent people.

WWW Sources

1)Freud's Theory

2)Freud Biography

3)Instinct Theory

4)Aggression Theories

5)Theories of Aggression

6)The Theoretical Development of Aggression

7)Aggression and Violence: Examining the Theories



Continuing conversation
(to contribute your own observations/thoughts, post a comment below)

01/14/2006, from a Reader on the Web

I have been curious about the relationship between frustration and aggression. We have had a family member that turned violent with a verbal attack and it appeared to me that he was frustrated or on some kind of crusade, what ever the case he apparently needs help. I would imagine that there are plenty of people that have to live near or co-exist with people with this condition. When information is made available for these people it helps them do the right thing when an up rising occurs. Thank you.


Additional comments made prior to 2007
to the one who asked about their family member. how about looking at ways that set this person off, or looking at when did this all start . if you can look for the beganning and if you can do so without passing jugment then you will be a great help to this person. just beleave ... Arthur White, 26 July 2006



please send me more information on the theory of Aggression, freud's theory, instict theory. iam deeply convinced that this is a good and beneficial website. thanks hope to hear from you . please i will be happy to receive these theories from you ... Njamba Alpha, 3 October 2006



can u help me with this question how best i can answer it: "How can the study of social influence explain acts of aggression? What can be done to reduce the negative impact of social influence on human behaviour?" ... Mitchell, 5 October 2006



I read the article here on "Theories of Aggression". Explaining Freud's work showing 5yr old male children have sexual urges for their mother and, though they love their father, they want him out of the picture.


My son just turned 6. For over two years he has been quite aggressive towards me, his father. It just gets worse as he gets older and stronger. I have to say we have a wonderful, loving relationship. I take a lot of time off work so we can be together and we do many projects and activities together. He demonstrates great affection and love for me. But nearly every day he gets into a mode where he starts hitting, scratching, biting, kicking, etc. and he won't stop. I have tried every tactic I can think of. If I do nothing he will seriously hurt me. At times throwing toys and other objects at me; and has drawn blood on more than one occasion. I find very little advice anywhere. My wife tells me to stop that with him; but fails to tell me how. She, and our female friends, are convinced I am instigating it. They seem to not have a clue. I search the Web and find nothing to help; except this article that gives one explanation. I love my son so much, and he is a fantastic son. A wonderful person. Any thoughts appreciated ... Arthur Clancy, 18 January 2007



I have a 39 yr old daughter .She attended a school for slow learners but was so well behaved and popular At age 11 puberty every thing changed in one week she became so violent she also had a grand mal seizure After a week or so she was her happy self again.This has gone on for 28 yrs. She has spent over 15 years in mental hospitals In Jan 2000 after much research I took it upon myself to give her 5mg of dex normally she would be handcuffed and taken by police to hospital where she would be put into a chemical straight jacket It worked !


Her weight went from 50kls to 115kls over those years the effects of the anti psychotic medication was horrendous and it was making her worse I was sure she did not have a mental illness nor did she have a.d.d as a child .The doctors treating her were a disgrace they were missing the key points of her illness Since Jan 2000 she has never been in hospital except for respite once.


She has lost50kls. I have named her illness hormonal A.D.D giving her dex every day does not help, the week of her period if you can give it to her she can be attacking you with a iron bar 5mg of dex and her behaviour settles within 20 mins She is also on 500mg sodium valporate for her seizures it does nothing for behaviour She has not had any anti psychotic medication since Jan 2000 She has the mental age of approx 8yr old but it varies through her monthly cycle.




Smerendip Visitor milka gakenia's picture

if aggression can be used as

if aggression can be used as a defence mechanism why not use it despite its effects?

obarafo mat's picture

aggresive client

i have a ten year old client, very aggressive in nature, that she can actually prove sturbon would not even want to learn, he injures his mates several time. i have tried all my best. what else could you advise me

A visitor's picture


Perhaps aggression and violence are driven by a mental virus / mental viruses. If you are interested in this theory, have a look here -

Paul Underwood's picture


It is Timothy McVeigh, not McVegh.

nyla's picture


helo i am doing my research on aggression among adolescents living in terrorism hit area can u plz help in some way.

Serendip Visitor's picture


Please read the book of j. Garbarino..dr.garbarino is specialist especialy children who witnesses war.

Serendip Visitor's picture

theories of aggression

this is a very good article which explain the theories in a simple yet efficient manner.

Michael Newman's picture

Theories of aggression

All existing theories of aggression, with all their diversity, can be divided into four main categories, considering aggression as: 1) innate urge or deposit (drive theory); 2) the need activated by external stimuli (frustration theory); 3) cognitive and emotional processes; 4) the actual manifestation of the social.

Serendip Visitor's picture

Theories of aggression

This is an excellent article, could you please tell me where I might be able to view the references? With thanks x

Anonymous's picture

very well explained :)thanks

very well explained :)thanks a ton