Agression. Flashcards
Agression: The specification details.
Neural and hormonal mechanisms in aggression, including the roles of the limbic system, serotonin and testosterone. Genetic factors in aggression, including the MAOA gene.
The ethological explanation of aggression, including reference to innate releasing mechanisms and fixed action patterns. Evolutionary explanations of human aggression.
Social psychological explanations of human aggression, including the frustration-aggression hypothesis, social learning theory as applied to human aggression, and de-individuation.
Institutional aggression in the context of prisons: dispositional and situational explanations.
Media influences on aggression, including the effects of computer games. The role of desensitisation, disinhibition and cognitive priming.
AG: T1. Biological explanations for Aggression: Explain the role of the limbic system in aggression.
The role of Limbic system in aggression.
Neural and hormonal mechanisms in aggression: The limbic system.
The Limbic system – is key area of the brain thought to be involved in moderating aggression. Serotonin and testosterone are also implicate in the behaviour.
The role of the Limbic system:
The Limbic system is a central part of the brain involved in processing emotional responses. It is this area of the brain that is implicated in aggressive behaviour and it is also thought that the works to mediate the level of aggression transmitted from that area.
It is thought that this happens by moderating testosterone levels in response to environmental triggers. More specifically, the amygdala – which is part of the Limbic system, is argued to have an important influence. If the amygdala malfunctioning any way due to a tumour, damage or atypical development then the levels of testosterone can be raised, making aggressive behaviour more likely.
Research support studies:
- Siegel et al (2009) – reviewed the research on the neurobiological and behavioural explanations of aggression (defensive and predatory). What they found: They found that both forms of aggressive behaviour seem to be controlled by the Limbic system. They also found evidence that the cerebral Cortext played an important role moderating the extent to which aggression was expressed.
- Raine et al (1997) – scanned the brains of 41 murderers and 41 controls. What they found: they found, using PET scans, that some had abnormalities in the way that their Limbic systems functioned. This suggests that the limbic system is involved in aggressive behaviour.
- Sumer et al. (2007) – reported on a case study of a 14-year-old girl who, following an MRI scan, was diagnosed with a tumour in the limbic system. This was investigated due to epileptic seizures from the age of three and she was behaving in an aggressive manner, expressing anger and rage. What they found: When the tumour was treated with drugs, the patient returned to normal levels of aggression. This seems to suggest that the high levels of aggression could have been prompted by the tumour in the Limbic system.
The limbic system comprises a set of structures including the:
· hypothalamus,
· the hippocampus
· and the amygdala.
One of its functions is concerned with processing emotional responses, which can be moderated by the cerebral cortex.
The amygdala is extremely important in moderating aggressive responses and many studies have identified its role in aggressive behaviour.
Despite the evidence for the involvement of the limbic system in aggressive behaviour, the fact that the limbic system is composed of many elements makes it difficult to say if a particular area is involved or if there are interactions between several areas. – Also the evidence is only correlational and so it is not possible to say for certain what is cause and what is effect.
Brief evaluation:
· The role of the Limbic system in aggressive behaviour is not clear cut. The Limbic system is made up of many components so it is not altogether clear which parts may be implicated. – it could equally be that there is an interaction between components of the system.
· The research linking brain abnormalities to violence is only correlational (as mentioned above) – this means that there is only an indication of aggression. There are also people who have Limbic system abnormalities who not demonstrate violent behaviour and so causation cannot be ascertained.
AG: T1. Biological explanations for Aggression: Outline the role of the neurotransmitter serotonin in aggression.
The role of the neurotransmitter serotonin in aggression.
Serotonin is a neurotransmitter in the brain which appears to have a widespread calming inhibitory effect, especially involving the pre-frontal cortex. It generally slows down and dampens neuronal activity.
Studies carried out on crayfish (Huberet al.,1997) have shown that those given additional serotonin delayed their withdrawal from fighting compared to those with normal serotonin levels. This could have been because their level of aggression was increased or because their natural responses were overridden. However, a crayfish is a crustacean, and so far removed from a human being, both physiologically and in its behavioural responses.
Studies on human beings have shown mixed results as to the involvement of serotonin in aggressive behaviour. As you look through the evidence, do bear in mind that the evidence for the role of serotonin is complex in that some studies show that high levels of serotonin increase aggression while some show the opposite.
Low levels of serotonin could be responsible for individuals being less able to resist the impulse to be aggressive. Brownet al.(1982) tested the cerebrospinal fluid of people exhibiting high levels of aggression and found that they tended to have low levels of waste products of serotonin, indicating low levels of serotonin in the brain.
It is thought that low serotonin levels result in a reduction in the control of the limbic system by the frontal cortex. This leads to more aggressive behaviour being displayed.
Even human studies suffer from issues of ecological validity due to the measures of aggression not being as realistic as everyday expressions of aggression.
- Studies carried out on crayfish .Huberet al.,1997. have shown that those given additional serotonin delayed their withdrawal from fighting compared to those with normal serotonin levels. This could have been because their level of aggression was increased or because their natural responses were overridden. However, a crayfish is a crustacean, and so far removed from a human being, both physiologically and in its behavioural responses.
Brief evaluation:
· The Crockett & Passamonti – study highlights why some people get aggressive when they have not eaten. Thus referred to the term “Hangry”. This could be due in part to depleted level tryptophan, which is the dietary source of serotonin. Foods such as eggs and chickpeas are tryptophan rich.
· Much research into neural and hormonal mechanisms in aggression involves animals, which poses a problem for extrapolating to humans. This research is conducted on animals for ethical reasons, and availability of animals, but there is always an issue of using animal studies to explain human behaviour.
· Using biochemistry to explain aggression I’d deterministic*. There is a limited amount of control of the individual over their biochemistry and so, of aggression is explained this way, it is also saying that the individual does not have much control over how they act. This has implications for the legal system and punishing violent crimes.
AG: T1. Biological explanations for Aggression: outline the role of the hormone testosterone in aggression.
Testosteroneactivates the subcortical areas of the brain to produce aggression. while cortisol and serotonin act antagonistically with testosterone to reduce its effects.
The role of the hormone testosterone in aggression:
Arguably the most widely known biological factor implicated in aggression is the male sex hormone testosterone.
It has been believed for a long time that an increase in testosterone levels leads to heightened aggression. This makes sense if you think about evolution and the male’s role in defending his territory, his mate and his offspring (we will talk more about this in the next topic).
Testosterone is produced in the testes, and castrated rats have been shown to display reduced levels of aggression. However, there is a difference depending on when they were castrated (Connor, Levineet al., 1969). If this happened when the rats were immature, later injections of testosterone did not reverse the loss of aggression. If they had been castrated as mature adults, though, their aggression could be reactivated by injections of testosterone. This means that there must be a developmental process involved in the sensitivity to testosterone.
There are several explanations as to how testosterone could influence aggressive behaviour.
} The enzyme aromatase, found in the limbic system of the brain, metabolises testosterone into estrogen. If its levels are changed, then the amount of testosterone will also change and this will lead to a change in aggressive behaviour. However, research on mice (Trainor, 2006) has shown a variety of responses to aromatase activity. One complication is that estrogen itself can influence aggressive behaviour. Some studies have shown an increase in aggression, whilst others have shown a decrease.
} The activity of the orbito-frontal cortex of the brain is reduced when testosterone levels are high. This will result in heightened aggressive responses in emotional situations.
} Serotonin activity can be reduced by testosterone and low serotonin levels may increase aggressive responses in humans (although, as you have seen, research findings are not all in agreement on this point).
This brief look at some of the mechanisms involving testosterone show how complicated the process is. It seems that testosterone not only has a direct effect on aggression but also mediates the effect of other chemicals.
The role of testosterone:
Testosterone is an androgen (male hormone). Females also have testosterone in their bodies but in much lower levels. Increased levels of testosterone are thought to be related to increased levels of aggression and of aggressive responses, such as provocation.
If a casual link is to he found then the mechanism behind how testosterone affects aggression levels needs to be documented. – some research on mice has suggested that the enzyme aromatase is implicated in the process.
Aromatase = an enzyme which helps metabolize (or process) testosterone.
· Aromatase is important in metabolising testosterone in the brain and is found in the Limbic region of the brain such as the amygdala. So, if there are reduced levels of aromatase in those areas then the testosterone in the brain will not have enough enzyme for it to activate. This means it will have less effect and the response to emotional situations experienced by the amygdala will not prompt a reaction in the testosterone in the system – thus reduces the likelihood of an aggressive reaction.
·
- Research by Higley et al. (1996) – suggests that testosterone levels are not the only factor in aggressive behaviours. They found that testosterone can affect how aggressive an individual feels but that they will not necessarily act on that feeling.
– Therefore it could be concluded that testosterone levels may underpin the emotional response to a situation but that other factors such as social norms will affect whether feeling aggressive influences the actual behaviour of the individual.
- · As with the research studies on serotonin, much of the work on testosterone in aggression has been carried out on non-human animals. This leads to problems of validity when generalising to humans. The use of self-report techniques to measure aggression in humans brings with it predictive validity issues.
· There are also correlational problems. Observing changes in testosterone and changes in aggression does notmeanthat the changing testosterone levels are causing the change in aggressive behaviour. It could be that aggressive acts lead to changes in testosterone. There could be other factors (e.g. environmental factors) involved too.
· It is argued that testosterone may be able explain only certain types of aggression. Simpson (2001) reports that testosterone is implicated only in inter-male aggression, but has no effect on other types of aggression.
· It is important to consider the measures used in research. Aggression is measured through questionnaires or responses to hypothetical scenarios and therefore the predictive validity (as mentioned above) is poor. – This means that someone may report high levels of aggression in a fake scenario on paper, but were it actually to occur in real life their response might be more passive. Testosterone can be measured using saliva samples and cerebrospinal fluid, both of which are reliable measures. However, hormonal fluctuations occur throughout the day so test-reset reliability may be low too.
Summarised:
As with the research studies on serotonin, much of the work on testosterone in aggression has been carried out on non-human animals. This leads to problems of validity when generalising to humans. The use of self-report techniques to measure aggression in humans brings with it predictive validity issues. There are also correlational problems. Observing changes in testosterone and changes in aggression does notmeanthat the changing testosterone levels are causing the change in aggressive behaviour. It could be that aggressive acts lead to changes in testosterone. There could be other factors (e.g. environmental factors) involved too.
AG: T1. Biological explanations for Aggression: Describe genetic factors in aggression, in particular the role of the MAOA gene.
Genetic factors in aggression, particularly the role of the MAOA gene.
The MAOA gene, which is sometimes nicknamed the ‘warrior gene’ – is implicated in aggressive behaviour due to excessive amounts of certain neurotransmitters in the system.
When you studied issues and debates in psychology in Unit 7, you looked at socially sensitive research. Here we have a classic example of this. Discovering a genetic factor involved in aggression carries the consequence of judging the guilt of people who carry out aggressive acts.
It is reasonable to look for genetic factors in aggression given therangeof evidence showing that aggressive behaviour is influenced by a variety of biological processes. The production of biochemicals is coded in the genome, as is the structural integrity of the brain. However, the environment affects the expression of the genotype, producing a particular phenotype. No single gene has yet been identified as directly causing aggressive behaviour but there has been evidence to show that the predisposition to exhibit aggression can be inherited.
- When you studied the genetic explanation for schizophrenia (section 6.2 in your textbook) you looked at evidence from twin studies, family relationships and adoption studies. Similar studies have been carried out to investigate the inheritance of aggressive behaviour.
Adoption studies have shown some similarities between the adopted child and its natural parents, which suggests genetic factors. However, similarities between the adopted child and the adoptive parents suggest that environmental factors are also involved.
MAOA gene.
Monoamine oxidase A (MAOA) is an enzyme that degrades neurotransmitters such as serotonin and dopamine in the brain: the more MAOA there is in the brain, the less of these neurotransmitters will be present The MAOA gene controls production of this enzyme. Various forms of this gene have been identified, including one which produces low amounts of MAOA and one which results in high amounts of the MAOA. Mice with a dysfunctional MAOA gene have been shown to exhibit more aggression to ‘intruder’ mice in experiments. We again have the validity issue here of generalising this to humans.
- Research into genetic profiles of various races of people has provided evidence of different MAOA genes in humans. For instance a study of New Zealand males found that those who had the low-activity version of the MAOA gene (MAOA-L) and suffered abuse were nine times more likely to indulge in antisocial behaviour and aggression.
The ‘Brunner syndrome’ is a description of MAOA deficiency. H G Brunner carried out research into the genotype of men in the Netherlands and their level of aggression.
Classic research: Abnormal behaviour associated with a point mutation in the structural gene for monoamine oxidase A study – H.G Brunner (1995).
The Brunner syndrome was first described in 1993 by H.G Brunner in his paper documenting the behaviour of five men in a family in the Netherlands. He found, through monitoring their urine samples, that they bad an excess of monoamines (noradrenaline, serotonin, and dopamine) in their bodies. This was caused by a monoamine oxidase A (MAOA) deficiency. They possessed a shortened version of the MAOA gene and therefore were not able to ‘mop-up’ excess amounts of neurotransmitters.
· The classic case study by Brunner shows how the MAOA gene can affect families that have the gene present in male members. The fact that for this Dutch family, there was such a high relevance of aggressive behaviour supports the MAOA gene theory.
Web research in context:
In the early 1990s, researchers linked low levels of MAO-A with increased frequencies of antisocial behavior, specifically when individuals had a history of being mistreated during childhood.
Later studies by Guo and colleagues (2008) investigatedMAOAvariants in 2500 American boys in grades 7 to 12, and demonstrated a genetic basis for severe aggressive behavior seen at school. A specific variant of the MAOA gene (VNTR 2R MAOA) was a risk factor of violent delinquency, but only when the boys suffered some other stress, such as family issues, low popularity and failing school.
Research (in depth):
- Moffit et al. (1992) – performed a study in 442 New Zealand males from birth to age 26, keeping a record of experiences of abuse and the presence of the shortened MAOA gene. It was found that those who had suffered abuse and had the low-activity version of the gene, were nine times more likely to indulge in antisocial behaviour, including aggression.
Genetic Factors in Aggression (research evidence) (Evaluation — AO3)
Strengths (AO3 — Evaluation):
(1) Point:Twin studies provide further support for the genetic explanation of aggressive behaviour.Example:For example, McGue et al (1992) found a correlation of +0.43 for MZ twins and +0.30 for DZ twins on aggression scales. This research demonstrates s stronger link to aggressive behaviour for identical twins.Elaboration:This suggests that genes play some part in aggressive tendencies as MZ twins share more genes than DZ twins, therefore if there was no genetic element to aggression we would not see any difference in the correlation for MZ and DZ twins.This is positive asit suggests genes may at least play a part in aggression and therefore that the cause of aggression is, in some part, biological.
Weaknesses (AO3 — Evaluation):
(2) Point:A considerable amount of research into genetic factors in aggressive behaviour was conducted on animals, such as Lagerspetz’s research on mice.
Evidence:For example, this means that the research only investigates the genetic factors in the development of aggression for animals and fails to generate any information regarding human aggression and links to genetics.
Elaboration:This is a weakness because, the findings from this research cannot beextrapolated (generalised)to humans.Mice and humans are physiologically different and so, although there seems to be a genetic basis for aggression in mice, it doesn’t mean that such findings can be generalised to humans.
You will notice that MAOA deficiency resulted in higher levels of serotonin which in turn was associated with high levels of aggression.
- The MAOA genehypothesiscan only explain the behaviour of one-third of men since two-thirds of men do not possess the MAOA gene variant which produces less of the enzyme. It is also an inadequate explanation for female aggression because it is rarely expressed in women.
AG: T1. Biological explanations for Aggression: Identify the advantages and disadvantages of the case study as a research method - such as in Brunners research.
The advantages of the case study as a research method.
Case studies are in-depth, detailed investigations of one individual (person or institute) or a small group. Brunner only studied five males in one family, which is why it is described as a case study. As such it has advantages, but also limitations. Think about these and list which you think are the most important of each.
· A significant advantage would be that the study would provide rich detail as it is an in-depth study carried out on a small sample.
· Extraneous variables still may factor into the study and with such a sample small, findings might then not be sufficiently generalizable.
Psych answers:
· You may have listed, as the most important advantage, the fact that the study would provide rich detail due to it being an in-depth study carried out on a limited sample. (It may even be theonly wayof researching a unique situation.) However, as it only investigates a limited sample, it is difficult to generalise the findings to a wider population.
· This highlights the trade-off between the idiographic versus the nomothetic approach. If individuals are the focus of a study, more information can be collected and the quality of the information is high. However there is the substantial risk that the participants are not representative of the general public.
· Despite this, the information gathered from case studies is extremely valuable as long as its limitations are kept in mind. Findings from one case study can refute evidence gathered by other methods that might, themselves, have validity issues.
· You might remember the case of ‘Genie’ which you examined during your
study ofattachmenttheory (Section 4 Topic 4).
This study questioned the notion of a critical age at which attachments and language can develop.
Other limitations of the case study approach include:
There may be a question of researcher bias since thedatais usually qualitative (non-numerical) rather than quantitative.
Reliance on memory is an issue since many case studies ask participants to recall events.
Case studies – summarised from the textbook (*repeat):
Case studies are in-depth, detailed investigations of one individual or a small group. They usually include biographical details, behavioural information and experiences of interest. Case studies allows researchers to examine individuals in great depth.
Explanations of behaviour are outlined in subjective ways, describing what an individual feels or believes about particular issues (ref: For example Koluchova’s (1972), ‘Czech twins’ study – page 133 in textbook).
Overall advantages of case studies:
· Rich in detail ~ case studies provide great depth and understanding about individuals and acknowledge human diversity. Because case studies are about ‘real people’, they have a feeling of truth about them. Information relates to a real person, not an average gathered from many.
· The only possible/ practical method to use ~ case studies allows psychologists to study unique behaviours or experiences that could not have been studied any other way. The method also allows ‘sensitive’ areas to be explored, where other methods would be unethical, like effects of sexual abuse.
You should recall that the advantage ofqualitative data– for example the aggressive behaviour studied by Brunner – is that it often tends to be more true to life and richer thanquantitative data. – The disadvantage is that it often suffers from subjectivity in its measurement and lacks detail.
AG: T1. Biological explanations for Aggression: Explain the use of content or thematic analysis to interpretqualitative data.
The use of content analysis and/ or thematic analysis to interpret qualitative data.
Themain difference between thematic analysis and content analysisis that thematic analysis is a method of qualitative data analysis that can be used with varyingresearch designs, while content analysis is a data analysis method that can be used to analyze bothquantitative and qualitative data.
In research and data analysis, researchers use different methods to analyze the data they gather. Thematic analysis and content analysis are the main data analysis methods most researchers use. But for most upcoming researchers, it can be confusing to clearly differentiate between thematic data analysis method and data content analysis method.
Thematic analysis is a data analysis method to analyze the qualitative and descriptive data a researcher gathers to solve his or her research problem. Once the researcher gathers data, he/she would carefully study the data multiple times in order to spot emerging patterns,themes, sub-themes, etc
Content analysis is a data analysis method that the researchers use to analyze both quantitative and qualitative research. Data content analysis allows the researcher to identify significant data out of a data corpus. When it comes to the world of research, researchers gather data from different sources in varying forms, such as pictures, books, ideas, photographs, papers, statues, ideas, behaviors, etc
Overall strengths of content analysis:
· Ease of application – content analysis is an easy-to-perform, inexpensive research method, which is non-invasive, as it doesn’t require contact with participants.
· Complements other methods – content analysis can be used to verify results from other research methods and is especially useful as a longitudinal tool (detecting trends; changes over time).
· Reliability – establishing reliability is simple as a content analysis is easy to replicate, through others using the same materials.
Overall weaknesses of content analysis:
· Descriptive – content analysis is purely descriptive and so does not reveal underlying reasons for behaviour, attitudes, etc. (The ‘what’ but not the ‘Why’).
· Flawed results – Is limited by availability of material; therefore observed trends may not reflect reality. For example, negative results receive more coverage than postive ones.
· Lack of causality – content analysis is not performed under controlled conditions and therefore does not show causality.
Thematic analysis:
Thematic analysis – a method of qualitative research linked to content analysis, which involves analysing data to identify the patterns within it, such as reporting themes (patterns), with patterns identified though data coding. Ultimately thematic analysis organises, describes and interprets data.
The identified themes become the categories for analysis, with thematic analysis performed through the process of coding which involves six stages:
- Familiarisation with the data – involves intensely reading the data to become immersed in its content.
- Coding – involves generating codes (labels) that identify features of the data important to answering the research question.
- Searching for themes – involves examining the codes and data to identify patterns of meaning (potential themes).
- Reviewing themes – involves checking the potential themes against the data, to see if they explain the data and answer the research question. Themes are refined, which can involve splitting, combining or discarding one.
- Defining and naming themes – involves a detailed analysis of each theme and creating an informative name for each other.
- Writing up – involves combining together the information gained from the analysis.
· Thematic analysis goes beyond just counting words or phrases, and involves identifying ideas within data. Analysis can involve the comparison of themes, identification of co-occurrences of themes and using graphs to display differences between themes.
AG: T1. Biological explanations for Aggression: Summary for Biopsychological explanations of aggression.
Summary for Biopsychological explanations of aggression:
The limbic system of the brain – the hypothalamus, hippocampus and amygdala – is implicated in aggressive behaviour.
The neurotransmitter serotonin and the hormone testosterone appear to influence aggressive behaviour, but the relationship in each case is complex.
Low levels of serotonin appear to increase aggression, but research findings are not consistent. For example, in Brunner syndrome, aggressive behaviour is associated with an excess of neurotransmitters due to a genetic defect.
The Brunner study is an example of the use of case studies to producequalitative dataon human behaviour. Although useful in some situations, the case study has limitations as a research technique.
Content analysis provides a means of convertingqualitative data, such as that produced by case studies, toquantitative datasuitable for further analysis.
Studies have shown that testosterone may increase levels of aggression, both directly and through its effect on other chemicals.
Twin studies have provided some evidence for a genetic component in aggression.
The MAOA gene may explain aggression in around one-third of western men who carry the shortened version of the gene.
Aggression is likely to be influenced by environmental factors such as experience of abuse.
AG: T2. Evolutionary/ Ethlological explanations for aggression: Describe the ethological explanation of aggression.
Fixed Action Patterns [FAP]
AO1
Lea [1984] analysed FAPs and identified 5 features:
- Stereotyped – behavior follows a certain pattern each time.
- Universal all the animals in that species use the same type of threat.
- Innate: all the animals in that species seem to be born with it and don’t have to learn it.
- Ballistic: Once it starts it cannot simply be stopped.
- Specific triggers seem to set it off.
Also:
Innate Releasing Mechanisms [IRM]
The Hydraulic Model of instinctive behavior [Lorenz 1950]
Ethology is where we learn about human psychology from studying other animals.
• Conrad Lorenz believed that aggression was an innate adaptive response – something which had evolved in humans and animals to help them survive.
• To see off predators: For example a group of hissing geese can drive off a fox, even though the fox would probably win a straight fight. If the geese survive, then the gene which led to that aggressive response will be passed on.
• To get resources: Lorenz also suggested that much aggression was aimed at members of the same species, when competing for territory or sexual partners, but some animals are so fierce they could easily damage each other when fighting for dominance; Eg. Wolves, Stags, Lions.
This would be maladaptive – bad for the species. Therefore they fight until one backs down, not to the death, just to establish who is stronger and who is weaker. Lorenz observed that most intra-species aggression consisted mainly of ritualistic signaling (e.g. displaying teeth) and rarely became physical.
This creates a society in which each individual knows their place. They have evolved ways of warning others to back off: Dogs bark and snarl, cats hiss, apes beat their chest or wave sticks about.
Niko Tinbergen called these Fixed Action Patterns [FAP]
AG: T2. Evolutionary explanations for aggression: Explain the role of Fixed Action Patterns [FAP], and the research of Tinbergen.
Innate releasing mechanisms (IRMs):
Fixed action pattern (FAP):
When the IRM is triggered by an environmental stimulus, a specific sequence of behaviour is released. This sequence is called a fixed action pattern (FAP) because it is universal and invariant across any one species. These behaviours are unaffected by learning and are ‘ballistic’, i.e. once triggered, the behaviour follows a set course and is not subject to alterations. Each individual behaviour is specific to a particular situation and is a response to a particular sign stimulus.
An example of fixed action pattern (FAP) of behaviour involving aggression is the make stickleback fish. The FAP starts with the nesting behaviour in spring. Establishing territory around the nest is important to the stickleback so any other make sticklebacks that encroach on territory are met with aggressive attacks. However, female sticklebacks are encouraged to stay so that they can lay eggs in the pre-prepared nests.
This behaviour was investigated by Tinbergen (1952) using models crafted to resemble male sticklebacks (with red bellies) and females (with swollen bellies). All male sticklebacks attacked the model designed to look like a make member of the species. – This shows that the behaviour is invariant (all males do it) and it is strong argument for the behaviour being innate.
- It is argued that fixed action patterns are adaptive because they increase evolutionary survival chances. This means that with regard to aggression in humans it must increase survival chances of it is to be regarded as a fixed action pattern. Ao3: This has proven to be one the issues in applying the theory to humans.
Brief note of evolutionary fitness:
The central concept of natural selection is theevolutionary fitnessof an organism. Fitness is measured by an organism’s ability to survive and reproduce, which determines the size of its genetic contribution to the next generation. However, fitness is not the same as the total number of offspring: instead fitness is indicated by the proportion of subsequent generations that carry an organism’s genes. For example, if an organism could survive well and reproduce rapidly, but its offspring were all too small and weak to survive, this organism would make little genetic contribution to future generations and would thus have low fitness.
If an allele increases fitness more than the other alleles of that gene, then with each generation this allele will become more common within the population. These traits are said to be “selectedfor”.
- The advantage of studying ethology is that we can look at behaviour in terms ofevolutionary advantage, which is difficult to do with humans who now live in artificial environments. Also, more control can be exercised over non-human animals in the laboratory than when studying human behaviours. (Your textbook gives further explanation on the role of ethology in understanding human aggression at the start of section 13.2).
Monkeys reared in isolation still exhibited species-specific reactions to pictures of other monkeys in various situations. This indicates that these behaviours are innate.
Research support with reference to Eibl-Eibesfeldt:
- Eibl-Eibesfeldt (1977) – argued a number of patterns of aggression in men are highly ritualised and are similar to behaviour found in animals. He cited warfare as an example. However, he also felt that there is an element of control that we are born with, which prevents us from massacring other ‘tribes’. This suggests, certainly from Eibl-Eibesfeldt’s point of view in the matter, that there is a distinction between the automatic processing of animals and the more considered processing of humans, so the ethological explanation has limited usefulness in actually explaining aggression in humans.
Evaluation of research (Ao3):
· An issue with explaining human aggression this way is that it should confer an evolutionary advantage. It is possible this happens in some circumstances, but in others where, for instance – a female is scared; she will not want the aggressor as her partner.
This reduces their chance of reproductive success and so does not show aggression to be an adaptive mechanism.
The fact that human responses vary in the same situation shows the invalidity of suggesting that humans have FAPs. Also, FAPs are not advantageous to humans as they are to non-human animals.
- Another problem in this research is that aggression is judged by outcome, i.e. killing or injuring another animal. However, the notion of aggression involves ‘intent’ and to observe one animal killing another does not allow intent to be assumed. Predatory behaviour cannot be said to be aggressive since no feeling of aggression is assessable.
Further research points:
Tinbergen presented male sticklebacks with a series of wooden models of different shapes. The red on the competing males’ underbelly is the stimulus that triggers the IRM that in turn leads to the aggressive FAP. He found that if the model had a red underside the stickleback would aggressively display and attack it, but no red meant no aggression. Once triggered, the FAP always ran its course to completion without any further stimulus.
Breland and Breland found that animals tend to revert to instinctive behavior regardless of training. This would support the FAP theory.
It could be argued that some behaviors are learned in the environment – but maybe not all. Dogs can been trained by hunters, army and police to act in particular ways.
Fixed action patterns are not that fixed – Hunt points out that sequences of behaviors that appear to be fixed and unchanging are greatly influenced by environmental factors and learning experiences – Lowers the validity of the theory as it suggests aggressive behaviors are affected by environmental influences
AG: T2. Evolutionary explanations for aggression: Explain the role of innate releasing mechanisms.
Innate Releasing Mechanisms [IRM]
IRMs are innate mechanisms that monitor drives and prompt behaviours following the presence of a stimulus.
FAP stands for a fixed action pattern. These are innate, fixed sequences of behaviour which are universal for a specific species. The behaviour is prompted by an innate releasing mechanism.
AO1
• Creatures have evolved an instinctive response to certain signs. [Like a red rag to a bull!]
Eg. Male sticklebacks will respond aggressively to the red underbelly of a rival male – but not to a female who does not have the red underbelly.
AO3
Cannot generalise to humans – We should be cautious about making such generalisations, especially to a complex behavior like aggression because humans can act upon free will unlike animals - Human aggression is extremely destructive but we seem to have an element of control (our processing might not be automatic / innate) - Aggression cannot truly be measured in animals because intent is not known and cannot be communicated (may be an act of survival, not aggression).
Innate releasing mechanisms (IRMs):
Konrad Lorenz was one of the earliest scientists to study ethology (the study of animal behaviour). He published a book calledOn Aggressionin 1963 and in it he described the innate drive of aggression. Lorenz likened aggression to other instinctive drives such as that for food. He suggested that aggression was ‘a need’ that had to be satisfied, and that animals had a specific neural circuitry inside the brain (this is the IRM) which monitored the drive.
Fixed action pattern (FAP) in relation to innate reading mechanisms:
When the IRM is triggered by an environmental stimulus, a specific sequence of behaviour is released. This sequence is called a fixed action pattern (FAP) because it is universal and invariant across any one species. These behaviours are unaffected by learning and are ‘ballistic’, i.e. once triggered, the behaviour follows a set course and is not subject to alterations. Each individual behaviour is specific to a particular situation and is a response to a particular sign stimulus.
It is believed that animals have a built-in neural structure (a network of neurons) which, when exposed to specific stimuli (signs or releasers) such as facial expressions, will cause the release of an automatic behavioural response (a fixed action pattern). This inbuilt biological structure or process is called the innate releasing mechanism (IRM). For example, when a dog sees a cat running away from them, they have an instinctive response to chase the cat. When the cat is still, the innate releasing mechanism is not activated; however, it is the cat running that activates the innate releasing mechanism
AG: T2. Evolutionary explanations for aggression: Describe The Hydraulic Model of instinctive behavior - by Lorenz 1950.
The Hydraulic Model of instinctive behavior [Lorenz 1950]
It may be easier to understand and remember the hydraulic model if you compare it to a toilet ! The water level gradually fills up till you flush it - then it has to be filled up again.
AO1
• Lorenz said that all creatures build up a reservoir of Action Specific Energy – you could call it “pent up aggression”. When the Innate releasing mechanisms [IRM] trigger the Fixed Action Pattern [FAP] all the aggression is fired off.
Once it is out of the system the animal is less aggressive again till the level of Action Specific Energy has built up again.
AO3
This explanation was probably an example of Lorenz trying to adapt Freudian ideas to animals! Freud wrote about the build-up of sexual energy [Libido] and Lorenz applied a similar idea here.
This theory fails to explain premeditated aggression and bearing grudges.
Holst [1954] found that instead of getting it out of the system , aggressive action could feed back to make the person more angry and increasingly more aggressive.
Arms et al. [1979] found that watching violent sport did not flush aggression out of the system but tended to increase it. Bushman does not agree with idea ofCatharsis– says that aggression may lead to more aggression.
AG: T2. Evolutionary explanations for aggression: Describe and Evaluate the evolutionary explanation for aggression. (A01/A03).
Evolutionary explanations of aggression.
Evolutionary Explanations of Human Aggression.
Explains aggression through natural selection (survival of the fittest, aggressive genes are passed on to subsequent generations as aggressive individuals more able to compete for resources)
The central idea of this topic is that for aggression to be an adaptive feature it has to serve a purpose.
Aggression is Adaptive
AO1
• David Buss has identified 7 adaptations of aggression in humans:
• Self Defence
• Reputation to ward off future aggression
• To achieve status – more allies less enemies
• Get and keep better share of resources. Pinker (1997) states aggression evolved in men to compete for women. This may have been the MAIN reason for aggression as there was no other property worth fighting over as we evolved.
• Deny own resources to children of rivals
• To prevent other males sharing the prime females
• Prevent partner being unfaithful. For example, sexual jealousy may have evolved to ensure that men pass on their own genes rather than allowing other males access to their mate.
Inter-Group Aggression
This is aggression between different groups, such as warfare and gangs.
AO1
•Bussstates human males have evolvedcognitive biastowards organised aggression: E.g.
• Cognitive bias to expect attack
• Cultivating tough reputation
• Use of vengeance as a deterrent
• Strategies for planning and timing an attack
• Deception and the ability to detect deception
•Cosmides and Tooby,the Military Contract: Men will only fight if those who share the rewards also share the danger. Other animals are not bright enough to work this out.
Intra-Group Aggression
This is aggresion within a single group, mainly linked to male rivalry and sexual jealousy.
AO1
• Daly and Wilson: Male – Male aggression among young men is common in all human cultures – suggesting it is evolutionary.
• Pinker (1997) suggests aggression evolved in men to compete for women. This may have been the MAIN reason for aggression as there was no other property worth fighting over as we evolved. Through most of evolution there was no money, no real property, so women were the only target of aggression.
• Potts and Hayden (2008): War and aggression aimed to control women’s mating habits since development of farming made inheritance of land important. Jealousy has evolved as a male response to the threat of infidelity. Jealous males are determined to pass on their OWN genes.
• Daley and Wilson (1988): Men may use jealousy and violence to control partners sexual behavior Violence is not intended to kill but may have that result. E.g. Fertile young women 10 times risk of domestic violence.
The evolutionary explanation depends on the premise that aggression has an important function both in terms of individual survival and reproductive success.
Men being aggressive to other men might serve to show off their attributes to possible mates. This may lead to greater reproductive sucess, furthering their genetic influence on future generations. This is similar to stags displaying during the rutting season.
Exhibiting the ability to fight for resources might make a male not only more able to survive themselves but appear more attractive to females since they can provide for their offspring.
Sensitivity is also important to females, however; if she saw this in a prospective male partner, she might feel they would be nurturing to her offspring, whereas she might feel her offspring could be in danger from their father if he were aggressive.
Jealousy can give rise to aggression due to a perceived potential threat to the relationship. This can confer anevolutionary advantagesince the aggressive behaviour can protect the relationship. Furthermore, aggression can prevent infidelity, which can pose a potential threat to the paternity of offspring. This has been supported by research showing that males are more violent towards partners who are about to leave them.
Research has shown that females are attracted to more dominant males, but do not necessarily think that such men are more likeable. They appear to put their own and their children’s survival ahead of their own happiness.
The evolutionary explanation:
The evolutionary explanation suggests that aggression serves an important function in terms of both individual survival and reproductive success. It can help an individual to fight for resources even if they are in short supply. It might also be, in the case of male aggression, that they appear more attractive to females as they would appear strong. Evolutionary psychologists argue that this would be attractive to women because they would be able to protect offspring.
Evolutionary theory also argues that humans have a natural tendency for aggression and this goes some way to dominate over other species.
The idea of men aggressive with other men is similar to the rutting of Stags, in that it is a chance to display attributes and especially show off to females. The victor is more likely to gain a mate or mates to reproduce with. – This means that they will father more offspring and have a greater chance of furthering their genetic influence on subsequent generations.
- There is much evidence to back up these claims, coming mainly from studies forced-choice, hypothetical scenarios.
Research support:
- Sadalla et al. (1987) – suggested that women are attracted to male dominant behaviours, supporting the idea that aggression in men can increase their chance of reproductive success. Interestingly, though, dominant behaviour may have enhanced their attractiveness, but it did not increase how much they were actually liked. It is possible that this shows that mate preference is based on survival rather than happiness.
Section 4: Evolutionary Explanations of Human Aggression.
Explains aggression through natural selection (survival of the fittest, aggressive genes are passed on to subsequent generations as aggressive individuals more able to compete for resources)
The central idea of this topic is that for aggression to be an adaptive feature it has to serve a purpose.
Aggression is Adaptive
AO1
• David Buss has identified 7 adaptations of aggression in humans:
• Self Defence
• Reputation to ward off future aggression
• To achieve status – more allies less enemies
• Get and keep better share of resources. Pinker (1997) states aggression evolved in men to compete for women. This may have been the MAIN reason for aggression as there was no other property worth fighting over as we evolved.
• Deny own resources to children of rivals
• To prevent other males sharing the prime females
• Prevent partner being unfaithful. For example, sexual jealousy may have evolved to ensure that men pass on their own genes rather than allowing other males access to their mate.
Inter-Group Aggression
This is aggression between different groups, such as warfare and gangs.
AO1
•Bussstates human males have evolvedcognitive biastowards organised aggression: E.g.
• Cognitive bias to expect attack
• Cultivating tough reputation
• Use of vengeance as a deterrent
• Strategies for planning and timing an attack
• Deception and the ability to detect deception
•Cosmides and Tooby,the Military Contract: Men will only fight if those who share the rewards also share the danger. Other animals are not bright enough to work this out.
Intra-Group Aggression
This is aggresion within a single group, mainly linked to male rivalry and sexual jealousy.
AO1
• Daly and Wilson: Male – Male aggression among young men is common in all human cultures – suggesting it is evolutionary.
• Pinker (1997) suggests aggression evolved in men to compete for women. This may have been the MAIN reason for aggression as there was no other property worth fighting over as we evolved. Through most of evolution there was no money, no real property, so women were the only target of aggression.
• Potts and Hayden (2008): War and aggression aimed to control women’s mating habits since development of farming made inheritance of land important. Jealousy has evolved as a male response to the threat of infidelity. Jealous males are determined to pass on their OWN genes.
• Daley and Wilson (1988): Men may use jealousy and violence to control partners sexual behavior Violence is not intended to kill but may have that result. E.g. Fertile young women 10 times risk of domestic violence.
General Criticisms of Evolutionary Research
AO3
Ethics:Waller says : Violence ,Xenophobiaand even genocide are adaptive, but this is very deterministic and unethical.
Ethics and Gender: Critics feel this theory could be used to justify violence against women. Buss himself always points out that we are not controlled by our genes, we have inherited the ability to learn and to choose.
Reductionist: Is this an over-simplification? Are there other issues which promote aggression such as culture or Individual differences in testosterone and cortisol.
Heredity & Environment: Are environmental factors a greater cause of aggression?
• Environmental stressors, heat, noise etc
• Cortisol levels in pregnant mother
• Childhood abuse and neglect
Deterministic: Evolutionary explanations may seem to suggest that aggression is natural but Figuerdo [1995] suggests jealousy and domestic violence are context specific not inherent, women are less likely to be victims of domestic violence if they have several brothers in town, so aggression can be controlled.
Socially sensitive– It suggests that aggression is somewhat excusable and out of the control of the individual committing the behavior – This has important consequences within the legal system – Brings into question the credibility of the theory and makes it imperative that such socially sensitive research is not released into the public domain
AG. T3: Social explanations for aggression: Describe/ recap the SLT approach to explaining behaviour, including Banduras research.
Social-Psychological explanations of Aggression.
Social learning Theory
In the 1960s Social learning theory seen as a challenge to behaviorists Suggested children learn things even without doing them, throughobservational learningand modelling.
Exam Tip: If the question asks about Social learning Theory it is not enough only to write about theBobo Doll experiment. That was only one experiment – not the whole theory.
AO1
Children learn aggressive behaviors through observing aggressive models. These may be live models such as parents or symbolic models such as characters in the media.
• Behaviorists believe learning occurs through experience followed by either punishment or reward. “Social Learning Theory” challenges that approach.
• The central idea of social learning theory is that people do not need rewards to learn aggression, they may copy the behavior of others, but this is less likely of they see the other people being punished.
Bandura states children learn by imitation, and are more likely to copy depending on:
The actual behavior of the role model
The status of the person copied
The closeness / immediacy of the person
How well we understand what is happening
Bobo Doll experiments: Children copied adults
Contributory factors:
Similarity: boys will copy boys, family links and groups etc.
Presentation: How close, live, immediate the violence was
Warmth: If the model was more friendly towards the subject
Prestige: If the model had high status
Appropriateness: If the behavior was “appropriate.
•Vicarious reinforcement: (i) Adult was rewarded children slightly more likely to copy; (ii) adult was punished children were much less likely to copy.
•Disinhibition: People are more willing to do things if they see that others are already doing them.
•Bandura’s conclusions: Aggression is not inevitable. Children observe aggressive behavior in others, but how they act may depend on what the consequences of aggression were, particularly for those they use as role models
AG. T3: Social explanations for aggression: Explian the frustration-aggression Hypothesis.
The frustration-agression hypothesis of aggression.
The frustration–aggression hypothesis.
This theory for aggression is based on the work of Dollard et al. They suggested that aggression is a consequence of feelings of frustration. Frustration is the feeling you experience when you are trying to achieve something, I.e. working towards a goal, and there are barriers (real or imaginary) that are preventing you from realising your aim. It is an unpleasant feeling and needs to be relieved. Aggression, the theorists argue, allows that relief to happen.
You almost certainly know what it feels like to be frustrated and that this can result in you feeling angry. In the case of the man whose garage was blocked by the car of a thoughtless driver, you can certainly feel his frustration. Maybe you can even excuse his actions, even if the law doesn’t.
Dollardet al. (1939) explored this idea and discovered a number of factors which resulted in this frustration being more likely to lead to aggressive behaviour:
The proximity to your goal: the nearer you are to achieving your goal, the more likely you are to become angry if something or someone prevents its achievement.
If the aggression will serve a purpose: certainly the man in the scenario above achieved his goal by taking out his frustration on the parked car.
If the blockage to the goal is deemed unreasonable: if the frustration is caused by a situation that can be rationalised, then you are less likely to get angry and exhibit aggression.
Research support for the frustration-aggression hypothesis:
- There has been extensive research carried out into the factors that turn frustration into aggressive behaviour. For instance, if someone jumps a queue and you are close to the front you are much more likely to react aggressively than if you are at the back of the queue (Harris, 1974).
- Pastore (1952) – explored justified frustration and showed that aggressive behaviour was lower when the frustration was unjustified.
- Jody Dill and Craig Anderson (1995) – used an origami exercise to explore the consequence of justified frustration. They had a confederate demonstrate the use of origami to make a complex paper model. In one scenario the demonstrator rushed the demonstration and excused this by saying he had to meet his girlfriend. In another situation the reason given was that the boss had told him he had to finish quickly. Participants were made angrier towards the demonstrator by the situation of meeting his girlfriend than when the boss was exerting pressure. A control group who were not frustrated reported less anger than both experimental groups. The measure of aggression was negative judgements made of the demonstrator.
- Leonard Berkowitz – believed that frustration might make us feel angry but that aggression will only be caused if other factors exist, such as environmental cues. A famous study was carried out into the ‘weapon effect’. Berkowitz and LePage (1967) – placed two guns next to a table where there was a shock generator. A confederate gave the participant electric shocks and then the participant was allowed to retaliate. The participant was more likely to apply a larger number of shocks in the presence of weapons compared to the situation of no weapons being present. This has led to a famous quote, ‘The finger pulls the trigger, but the trigger may also be pulling the finger.’
- Buss (1963) – examined whether different types of frustration would affect the likelihood of aggression occurring. He used three different types of frustration:
(1) Failure to win some money.
(2) Failure on a task.
(3) Failure to get the grade you expect.
He found that all types of frustration prompted aggression and all three types prompted higher levels of aggression than a group that acted as a control group with no frustrations, thus supporting the theory.
+ Application to intergroup relations:
· In the realm of intergroup relations, the frustration-aggression hypothesis was used to shed light on thedynamicsofstereotyping,prejudice, and out-group hostility. The theory of scapegoating is probably the most well-known application of the frustration-aggression hypothesis to the study ofprejudice.
· Drawing in part onFreudianconcepts of displacement, projection, andcatharsis, the scapegoating theory held that once frustration and theimpetusfor aggressive behaviour have occurred, it makes relatively little difference who receives the brunt of theviolence.
· In some cases, aggression naturally takes the form of retaliation against the initial source of frustration. In other cases, situational constraints can prevent a person from being able to react against the actual source of frustration (such as when the frustration was caused by a very powerful person or group). In still other cases, such as natural disasters, there may be no one to blame, but the frustration can still produce aggressive inclinations.
· According to the theory, thedisplacementof aggression onto a socially sanctioned (i.e., convenient) victim group serves several purposes. First, and most important, it channels the expression of aggressive impulses and createscatharticrelief once the aggression has been released. Second, it is socially undesirable to behave violently toward others in the absence of justification, but prejudicial attitudes can be used to justify (or rationalize) the expression of hostility. In that way, members of disadvantaged groups can be blamed for their own plight as targets of hostility and prejudice. Finally, in accordance with psychoanalytic thought, the theory of scapegoating suggests that victim blaming isexacerbatedby the projection of (typically unconscious) guilt that frustrated parties feel as a result of their own prejudice and violent activity.
Evaluation of the frustration–aggressionhypothesis:
· Not all frustration leads to aggression and so it matters that the source of the aggression is considered.
· Not everyone will react aggressively given the same situation: some people’s response is to cry or get despondent, so personality and personal experiences must be taken into account. Social learning theory is the subject of the next part of this topic and it will show how personal experiences can influence our behaviour. This raises the issue of nomothetic versus idiographic explanations (Unit 7 Topic 8).
· There are causes of aggression other than frustration and so the frustration–aggressionhypothesisdoes not explain all aspects of aggressive behaviour.
· There are problems of validity with many of the studies into aggressive behaviour, since it is unethical to create actual aggressive behaviour in humans. For example, in one of the studies above the measure of aggression was a judgement about the demonstrator. Very often the measure of aggression is a person’s response to hypothetical situations and in reality they might behave very differently. – This has low predictive validity because in reality they may act qualitatively different.
· Finally, the nature of the connection between perceived frustration and the display of violence also turned out to be more complicated than Dollard and his collaborators realized. In the most empirically successful modification of the original frustration-aggression hypothesis, the American social psychologist Leonard Berkowitz suggested that frustration is a psychologically aversive state that can create a predisposition to behave aggressively. According to Berkowitz, frustration will lead to aggression to the extent that it elicits negative emotions. Moreover, frustration is only one form of unpleasant negative affect that can provoke violent responses.
- The general idea was that aversive experiences produce negative emotions and feelings, as well as related thoughts and memories of past reactions to negative events. Berkowitz noted that such negative emotions and thoughts lead automatically to thefight-or-flight response. The choice between “fight” and “flight” was thought to depend on the intensity of the negative emotion as well as on the subjective appraisal and interpretation of the situation.
