Aggression Flashcards
Neural Influences - The Limbic System
- A system of structures such as the amygdala, hippocampus and hypothalamus that is associated with emotional behaviour.
The Amygdala
-Responsible for quick evaluation of the emotional importance of sensory information and prompting an appropriate response.
The Hippocampus
-Involved with the formation of long-term memories, and so allows an animal to compare the conditions of a current threat with similar past experiences.
Serotonin
- A neurotransmitter that in normal levels exerts an inhibitory calming effect on neuronal firing in the brain.
-Low levels of serotonin remove the inhibitory effect with the consequence of individuals being less able to control impulsive and aggressive behaviour (the serotonin-deficiency theory).
Evidence for Serotonin’s Effect on Aggression - Dexfenfluramine(DXF)
-Mann et al (1990) gave 35 healthy ppts DXF which is known to deplete serotonin.
-Then using a questionnaire to assess hostility levels, they found DXF treatment in males was associated with an increase in hostility.
Hormonal Influences - Testosterone
-Produced mainly in the testes in males is associated with the development of secondary sexual characteristics, and has been associated with aggressive behaviour.
Genetic Factors - Twin Studies
- MZ twins share all their genes, whereas DZ twins only share 50%, if MZ twins are more alike in terms of aggressive behaviour, this should be due to genes rather than environment.
Limitation of Twin Studies
-Higher concordance rate in monozygotic twins may be due to a bigger similarity in their environment.
One limitation of adoption studies is that adopted children are also matched with families that are similar to their biological families.
This means that any similarity between the child and their biological parent might be due to similarities in their environment, as well as their genetics.
Limitation of Twin Studies
-They assume that the environment will have the same impact on the behaviour of both monozygotic and dizygotic twins.
Genetic Factors Adoption Studies
-Helps untangle the effects of environment and heredity in aggression.
-If a positive correlation is found between aggressive behaviour in adopted children and aggressive behaviour in their biological parents = a genetic correlation is established.
-However, if a positive correlation is found between adopted children and aggressive behaviour in their adoptive parents = an environmental correlation is established.
-Lack internal validity
Research Support for the Genetic Explanation
Christiansen conducted a twin study comparing the concordance rate for criminal behaviour for monozygotic and dizygotic twins.
-He found a concordance rate of 55% for the monozygotic twins and a concordance rate of 22% for the dizygotic twins, indicating that genetics plays a role in determining aggression.
Gene for Aggression: MAOA
-Whilst there is no individual gene for aggression, the MAOA gene regulates serotonin production in the brain, low levels have been associated with impulsive and aggressive behaviour.
Brunner’s Dutch Family Study
-Support for MAOA Gene
-A Dutch family found that many of its male members behaved in a particularly violent and aggressive manner, these men were to have abnormally low levels of MAOA in their bodies. - (MAOA-L)
MAOA-L
Those with the MAOA-L gene variant were significantly more likely to grow up to exhibit anti-social behaviour.
Ethological Explanation
-Focuses on understanding innate behaviors, particularly aggression, by studying animals in their natural environments
-Stresses the adaptive value of animal behaviours.
Innate Releasing Mechanism(biological structure)
-A neural network that when stimulated by the presence of a sign stimulus, activates the fixed action pattern associated with sign stimulus.
Fixed Action Patterns
-A repertoire of stereotyped behaviours which occur in specific conditions.
Action-specific Energy
-The Hydraulic Model
-The buildup of a motivational drive or pent-up aggression within an organism.
-After performing the FAP, the reservoir of ASE is empty and the behaviour cannot be repeated until the ASE has built up again - The Hydraulic Model
Ethological Explanation Process
-Sign Stimulus(environmental cue)
triggers
-Innate Releasing Mechanism(biological structure)
triggers
-Fixed Action Pattern
Ritualistic Aggression
-Not all aggressive behaviour involves fighting and may be ritualised in the form of threat displays.
-Ritualistic aggression makes acts of violence less likely to occur-threat displays make an opponent back down and are the last step before an animal either fights or submits.
Lorenz’s Research
-Claimed species have instinctive inhibitions that prevent them using weapons against members of their own species.
-E.g. When two wolves fight, the losing individual will expose its neck to. its adversary to show submission - then instinctive inhibitions prevent the dominant animal from continuing the fight.
-Lorenz claimed as humans do not have powerful natural weapons- we have no instinctive inhibitions against killing one another.
Evolutionary Explanations
-Sexual Competition
1)Ancestral males seeking access to females would have had to compete with other males - eliminating the competition through aggression.
2)Those who successfully used aggression
3) More successful in acquiring mates
4) More successful in passing on their genes to offspring.
5) Leading to the development of a genetically transmitted tendency to be aggressive to other males.
Evolutionary Explanations
-Sexual Jealousy
-Aggression in the form of sexual jealousy results from paternal uncertainty.
-Men are always at risk of cuckoldry - and there is therefore an adaptive function of deferring a mate from sexual infidelity - minimises risk of cuckoldry.
Aggression in Warfare
-Any behaviour associated with warfare would have evolved because of the adaptive benefits for the individual and their offspring.
-Livingstone Smith claimed that human warfare originated to obtain valuable resources and to attract mates and forge intagroup bonds.
Frustration-Aggression Hypothesis - Dollard
-Sees aggression being the consequence of frustration, defined as any event or stimulus that prevents an individual from attaining some goal and its accompanying reinforcing quality.
Frustration-Aggression
-Catharsis
-The hypothesis states that aggression can cause catharsis - a form of emotional release that is achieved by the person engaging in aggressive behaviour.
Justified Aggression
-Aggressive behaviour that is perceived as socially acceptable or even warranted due to a perceived wrongdoing.
Unjustified Aggression
-Aggressive behaviour that isn’t perceived as a legitimate response to a situation or provocation.
-Produces more anger and aggression.
Displaced Aggression
-Dollard et al assumed that aggression is sometimes displaced from the source of the frustration on to someone else.
-This may be due to the source of frustration being too:
-Distant
-Abstract
-Animated
Revised Frustration-Aggression Hypothesis - Berkowitz
-Claimed that frustration is only one of many different types of unpleasant experiences that can lead to aggression.
Social Learning Theory - Observation
-Children primarily learn their aggressive behaviours by watching the behaviour of role models and then imitating that behaviour.
-Vicarious Reinforcement - Children witness many examples of aggressive behaviours at home, school, on tv and in films.
-By observing the consequences of aggressive behaviour for those who use it, a child gradually learns what behaviour are punishable and what behaviours should be repeated.
SLT - Mental Representation
- Bandara claimed that children must form mental representations of events in their social environment including possible rewards and punishments for their aggressive behaviour.
Self-Efficacy
-Children develop confidence in their ability to carry out necessary aggressive actions - those who have been less successful in past aggressive behaviours have a lower self-efficacy.
SLT : Key Study
-Bandura’s Bobo Doll
De-individuation
- A psychological state in which individuals have lowered levels of self-evaluation and decreased concerns about evaluation by others.
Nature of De-individuation
-Presence of large crowds gave people a cloak of anonymity that diminished any personal consequences for their actions. There is a diminished fear of the negative evaluation of actions and a reduced sense of guilt.
The Situational Explanation: The Deprivation Model
-Emphasises the causes of a particular behaviour as being due to the context in which it occurs rather than any enduring characteristics of the individuals involved
-The specific deprivations that inmates experience are linked to the increase in violence, including:
-Loss of liberty
-Loss of autonomy
-Loss of security
-This explanation argues that prison violence is due solely to prison-specific. variables, rather than inmate characteristics.
Institutional Aggression in Prisons
-Refers to aggressive acts that are found in particular violent institutions such as prisons, two models explain the aggression found in these places - The Deprivation Model & The Importation Model
The Deprivation Model: The Role of Prison Characteristics
- Cooke et al claimed prisons are only violent in these circumstances:
-Overcrowding
-Heat & Noise
-Job Burnout
The Dispositional Explanation:
The Importation Model
-Emphasises the causes of a particular behaviour as being due to the enduring characteristics of the individuals involved.
-Claims that inmates bring their violent pasts into prison and draw on their experiences in an environment where toughness and physical exploitation are important survival skills.
-In many cities, street culture has evolved into a ‘code of the streets’ which sets violence as a precedent.
The Importation Model: Gang Membership
-Many studies have found that gang members disproportionately engage in acts of prison violence - members of street gangs offend at higher levels while in prison than their non-gang counterparts.
-They account for a majority amount of serious and violent crimes in prison.
Media Influences on Aggression
-Violent Films & TV - Laboratory & Field Experiments
-Researchers randomly assign participants to either an experimental condition where they view violent film scenes - or a control condition where they watch non-violent film scenes.
-A consistent finding in both experiment types is that those who watch violent scenes subsequently display more aggression.
Media Influences on Aggression
-Violent Films & TV - Longitudinal Studies
-Allow researchers to track individuals over time in order to assess the impact of early experiences on behaviour in life.
Longitudinal Studies - Example
-Huesmann et al 2003 studied 500 children between the ages of 6 and 10 - 300 of these children were studied 15 years later - Huesmann found that habitual early exposure to TV violence was predictive of adult aggression later in life.
Media Influences on Aggression
-Violent Films & TV - Meta-analysis
-Allow researchers to aggregate the findings of many different individual studies of the effects of media violence.
Media Influences on Aggression
-Violent Computer Games
-Research suggests that intervative violence in video games has the potential to exert even more influence than TV violence.
-As the viewer plays a more passive role watching TV - whereas during violent game play, aggression is rewarded and is portrayed as being both appropriate and effective.
Media Influences on Aggression
-Violent Computer Games - Experimental Studies
-Anderson & Dill found that ppts blasted their opponents with white noise for longer and rated themselves higher on the state hostility scale after playing a violent video game compared to those who played a slow-paced puzzle game.
Explanations of Media Influences
-Desensitisation
-Assumes that under normal conditions, anxiety about violence inhibits its use - media violence may lead to aggression by removing this anxiety.
-The more televised violence a child watches, the more acceptable aggressive behaviour becomes for that child - frequent viewings of television violence may cause children to be less anxious about violence.
Effects of Desensitisation
-A child who becomes desensitised to violence may therefore perceive it as more normal and be more likely to engage in violence themselves.
Explanations of Media Violence - Disinhibtion
-States that exposure to violent media legitimatises the use of violence in real life because it undermines the social sanctions that usually inhibit such behaviour.
Explanations of Media Violence
-Cognitive Priming
-Refers to a temporary increase in the accessibility of thoughts and ideas. E.g. violent media activates thoughts about violence which activates other aggressive thoughts - through association in memory pathways.
