IntroductionA person can be aggressive because of their biological make-up; they are aggressive people naturally. 1) Do you agree with the above statement and why? 2) What biological factors could account for aggression?

Topic Aims

To understand factors affecting aggression and the evidence for these including: Brain areas – the limbic system and the amygdala Hormones Social learning theory

Two areas of the brain linked with aggression:1. The limbic system2. The amygdale

The limbic system

The limbic system is a set of brain structures in the middle of the brain. The limbic system is called the emotional area of the brain because it is responsible for emotions needed for survival, like fear and aggression. Research has focused on amygdala, within the limbic system.

The amygdala

The amygdala is a structure in the brain that recognizes emotion. If someone smiles we know they are happy and if they frown we know they are sad. The amygdala also creates emotional responses. You have probably seen a frightened cat; it bares its teeth and hunches its back. This is the amygdala producing a fear response. The amygdala is also responsible for producing aggression. Evidence: In animal studies, if the amygdala is removed the animal becomes very calm and does not respond to threatening situations with aggression. Damage to this area of the brain may cause increased levels of aggression.

Case study – Charles Whitman

In 1996 Charles Whitman killed 13 people from an observation tower at Texas University, after killing his wife and mother. He left behind a note asking doctors to examine his brain as he was convinced that something was making him aggressive. He was found to have a brain tumour pressing against his amygdala. Video: http://www.huffingtonpost.com/2012/03/27/mind-murderer_n_1384102.html

Evaluating the link between biology and aggression

Strengths: Animal studies that have involved damage to or removal of the amygdala offer evidence for its link with aggression.

Do TV and Video games affect young people’s behaviour?01 Biology of aggression and social learning theory

The case study of Charles Whitman and the case describe by King (1961) [see textbook page 95] are evidence for its link with aggression in humans. Furthermore, the Telegraph article ‘Brain tumour 'turned teacher into paedophile' offers additional support.Weaknesses: Studying the human brain is difficult and can be very risky, so there is no way of making sure areas of the brain are linked to aggression.

Animals and humans are different in many ways, so animal research suggesting a link between the brain and aggression may not be applicable to humans.

Case studies are unreliable, as the reason for an individual’s aggression may be unique to that individual, i.e. Charles Whitman is a one-off case.

Do TV and Video games affect young people’s behaviour?01 Biology of aggression and social learning theory

L2: Male aggression and testosteroneIn almost every culture, males are far more aggressive than females. Could this be because they have more testosterone? Testosterone is a male sex hormone (or could it be the result of social expectation…) Hormones are chemicals produced by the body that send messages to organs of the body via the bloodstream.

Testosterone is secreted by the adrenal glands and testes and is needed to produce sperm, develop the male reproductive organs and produce male features, such as facial hair and a deep voice. Women also have testosterone, but males produce up to 10mg of testosterone every day, which is ten times more than a woman.

Aggression in animals

Psychologists have searched the role of testosterone by studying animals. Injecting animals with testosterone or removing the testes

leads to increased or decreased levels of aggressions.

Castrating a male animal lowers its testosterone levels. This makes animals less aggressive. But if the same animal is then injected with testosterone its aggression is restored to a level similar to that before the castration.

This is strong evidence that testosterone is responsible for aggression.

Aggression in humans

Psychologists can take blood from humans to see what level of testosterone they have and compare to this to how aggressive they feel or act. Some correlation studies (studies that see if there is a link between two variables) have found a relationship between high testosterone levels and questionnaire results showing greater reported aggression. However, it is not certain whether testosterone causes increased aggression or aggression causes increased testosterone.

Evaluating the role of testosterone

Strengths: In animals, there is a clear cause and effect relationship between testosterone and aggression. Human studies show a relationship between aggression and testosterone in correlation studies.

Weaknesses: Not all humans with high testosterone levels are aggressive. Some have greater sporting ability or are driven in their careers. Testosterone creates a drive, but this need not be a violent one.

If testosterone is the cause of aggressive behaviour, why are some women more violent than some men, and why aren’t all men violent?

Do TV and Video games affect young people’s behaviour?01 Biology of aggression and social learning theory

L3: Social learning theory as an explanation of aggressionObservational learning: Children learn through watching other people. The child remembers and copies this action and performs it itself. This is called observational learning.

Modelling is the act of copying an observed behavior. If a parent frequently reads books, the child may model this behavior by picking up books, opening them and turning pages.

Role models: A person we observe and learn from is called a role model. This can be anyone we watch, such as a sporting hero, celebrity, teacher or parent.

Identification: Is when we adopt the behaviours, attitudes and beliefs of a role model. We become like them and believe we can do what they do.

Vicarious learning: We are more likely to imitate someone if we think that there will be a reward in it for us. Vicarious learning is when we learn from the fortunes or misfortunes of others. Vicarious punishment is where we are learn through consequences of other people’s actions. We do not have to receive reward or punishment ourselves.

In the 1960s the psychologist Albert Bandura found that children were more likely to copy an adult attacking a large inflatable doll (known as Bobo doll), if the adult was rewarded for it. If the adult was punished the child would be less likely to copy. Bandura’s study seems to support the idea that boys were more likely to copy physical aggression than females.

Do children copy TV and video games?

If we use social learning theory to understand how TV and video games change the behavior of young children, then we should believe that watching violence could make children aggressive. Young people do watch programmes and play games that are not suitable for their age group, and observational learning of aggression or violent behavior can occur.

Many children act out the behaviour of their favourite television or video game characters. You only need to watch small children for a little while to be able to pick out the fighting moves of their favourite superheroes or the dance steps of their pop idols.

Evaluating social learning theory as an explanation of aggression

Strengths: Banduras (1961) study supports social learning theory because he found that children do copy aggression. Many tragedies, such as school shootings, have been linked to TV and video game violence.

Weaknesses: It could be that aggressive children watch aggression on TV and play violent video games rather than being affected by them. They could be naturally

Do TV and Video games affect young people’s behaviour?01 Biology of aggression and social learning theory

aggressive. Watching violent TV and video games can actually lower aggression. This is because it acts as a release for natural aggression.

Comparing the biological and social learning theories of aggression

The biological approach sees aggression as something that comes from within us, whereas the social learning theory believes that aggression is copied from others external to ourselves.

Social learning theory argues that we are likely to be motivated to copy aggression through vicarious reinforcement, whereas the biological approach emphasizes amygdala damage or testosterone imbalance.

Difficulties with each theory

Not all individuals with high level of testosterone or who watch violent TV and video games are actually aggressive. Neither theory takes account of differences between individuals.

Both have been criticized because the reverse of each theory might be true. Aggressive children might seek out aggressive media rather than the media affecting the behavior. Similarly aggression might cause high testosterone levels rather than testosterone causing aggression.

Nature vs. Nurture

As we have seen, the biological side of the discussion says that the way we behave is determined by how our brain and hormones function. The brain controls our behavior, and if it is damaged in some way it can affect how we behave. If we have hormone imbalance, this can affect our behavior too. High levels of testosterone can increase aggression according to this theory. This is the nature side of the debate because the cause of aggression comes from within us.

The nurture side of the debate says that our environment causes behavior. This includes the way we are brought up, the people we learn from and the experiences we have. All of these guide us to behave in a certain way. Social learning explains how we identified with others and model their behavior. It argues that aggression is caused by the environment in which we live- whether we are exposed to aggressive media or not.

A conclusion

It seem sensible to explain aggression in terms of combination of both factors. Nowadays most people believe that it is a combination of nature and nurture that makes us who we are and influence how we act.

Do TV and Video games affect young people’s behaviour?01 Biology of aggression and social learning theory