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Aggression

Aggression can be any physical or verbal behavior intended to hurt or destroy.

It may be done reactively out of hostility or proactively as a calculated means to an

end.

Research shows that aggressive behavior emerges from the interaction of biology

and experience.

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The Biology of Aggression

Three biological influences on aggressive behavior are:

1. Genetic Influences2. Neural Influences3. Biochemical

Influences

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Influences

Genetic Influences: Animals have been bred for aggressiveness for sport and at times for research. Twin studies show aggression may be genetic. In men,

aggression is possibly linked to the Y chromosome.

Neural Influences: Some centers in the brain, especially the limbic system

(amygdala) and the frontal lobe, are intimately involved with aggression.

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Influences

Biochemical Influences: Animals with diminished amounts of testosterone

(castration) become docile, and if injected with testosterone aggression increases. Prenatal exposure to testosterone also increases aggression in female hyenas.

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The Psychology of Aggression

Four psychological factors that influence aggressive behavior are:

1. dealing with aversive events;2. learning aggression is

rewarding;3. observing models of

aggression; and4. acquiring social scripts.

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Aversive Events

Studies in which animals and humans experience unpleasant events reveal that those made miserable often make others

miserable.

Ron Artest (Pacers) attack on Detroit Pistons fans.

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Environment

Even environmental temperature can lead to aggressive acts. Murders and rapes

increased with the temperature in Houston.

Physical Discomfort & Aggression

• Heat• Humidity• Pain• Noxious fumes• Poverty• Crowding

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Frustration-Aggression Principle

A principle in which frustration (caused by the blocking of an attempt to achieve a desired goal) creates anger, which can

generate aggression.

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Learning that Aggression is Rewarding

When aggression leads to desired outcomes, one learns to be aggressive.

This is shown in both animals and humans.

Cultures that favor violence breed violence. Scotch-Irish settlers in the South

had more violent tendencies than their Puritan, Quaker, & Dutch counterparts in

the Northeast of the US.

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Observing Models of Aggression

Sexually coercive men are promiscuous

and hostile in their relationships with

women. This coerciveness has increased due to

television viewing of R- and X-rated

movies.

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Acquiring Social Scripts

The media portrays social scripts and generates mental tapes in the minds of the

viewers. When confronted with new situations individuals may rely on such

social scripts. If social scripts are violent in nature, people may act them out.

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Do Video Games Teach or Release Violence?

The general consensus on violent video games is that, to some extent, they breed violence. Adolescents view the world as hostile when they get into arguments and receive bad grades after playing

such games.

Media Violence

• More TV sets in United States than toilets– Media consumption is #1 pass-time among

Americans, particularly youth• 60%-70% of all TV programs contain

violence– 70%-80% show no remorse, criticism, or

penalty for the violence• By the time the average American child

graduates from elementary school:– More than 8,000 murders– More than 100,000 other acts of violence

(e.g., assaults, rape)

Media Violence

• More recently, video games have become kids’ favorite form of media

• 90% of kids age 2-17 play regularly

• Majority of popular games are violent

Grand Theft Auto

Media Violence

• Since at least 1970, researchers have known of a link between violent media and aggression– Weakened inhibitions against violent

behavior– Imitation of specific violent acts– Aggression primed as a response to anger– Desensitization to violence– Overestimation of prevalence of violence in

real life

Common Responses

1. “That’s all boloney. I play those games and I’ve never killed anyone.”

2. “Maybe there is an effect, but it’s really small and meaningless.”

3. “Actually, my friends and I feel better after blowing off steam playing video games.”

Common Responses

1. “Not all who play violent games/watch violent media become killers.”– True. Not all smokers die of lung

cancer, either.

• The point is NOT whether exposure leads inevitably to criminal mayhem, but that the likelihood of aggression is increased

Effects of VVGs(Bushman & Anderson, 2001)

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Aggression Helping HostileThoughts

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Arousal

Common Responses

2. “Effects are trivially small”– False. Effects are larger than many

that we take for granted

Common Responses

3. “Playing violent games/watching violence allows people to “vent” feelings of anger”– False. Watching violence or engaging

in virtual violence increases aggression

– Catharsis doesn’t work!

Media Industry Response

1. The media is simply “holding a mirror to society.” – False. Real world is far less violent than the

TV/Movie world.

– 0.2% of crimes are murders; 50% of crimes on TV are murders

– Average of 7 characters are killed on TV each night• If applied in reality, this proportion of murder

would wipe out U.S. population in 50 days

Media Industry Response

2. “We’re simply giving the public what they want.”– Maybe. But viewer interest is only one

factor driving programming decisions

– Societal violence can be considered a hazardous by-product

– Also, most popular shows (Friends, Seinfeld, Bachelor) are not violent

Media Industry Response

3. “Violence sells!”– False. TV violence significantly

decreases memory for commercial messages

– Bushman, 1998• 19% of viewers will be less likely to

remember an ad if it is embedded in a violent or sexually explicit show

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Summary