Aggression Flashcards
What is aggression?
It is an act carried out with the intention to harm another person.
What is proactive aggression?
‘Cold-blooded’ – it’s a planned method of getting what you want and so it is less emotional e.g. bullying, domination, teasing, name-calling.
What is reactive aggression?
‘Hot-blooded’ – it’s angry and impulsive, and is accompanied by physiological arousal e.g. temper tantrums, vengeance. This type of aggression is probably responsible for a greater proportion of society’s problems and so psychologists tend to be more interested in it.
What are neural mechanisms of aggression?
Areas of the brain and how they communicate (e.g. neurotransmitters) that may be responsible for aggression.
What is the limbic system?
A set of subcortical structures in the brain that are thought to be closely involved in coordinating and regulating emotional behaviour, including aggression.
Which two brain structures in the limbic system are thought to be involved in aggression? For each structure, explain how they are involved in causing aggression.
The amygdala:
This is the most important structure in aggressive behaviour. The amygdala plays a key role in how an organism assesses and responds to environmental threats and challenges. It is responsible for quickly evaluating the emotional importance of sensory information and prompting an appropriate response. Greater reactivity (or stimulation) of the amygdala in humans is an important predictor of aggressive behaviour.
The hippocampus:
The hippocampus is involved in the formation of long-term memories, so an animal can compare the conditions of a current threat to similar past experiences. For example, if an animal had previously been attacked by another animal, the next time they encounter that animal they are likely to respond with aggression or fear.
Impaired hippocampal function prevents the nervous system from putting things into a relevant and meaningful context, and so the amygdala may respond inappropriately to sensory stimuli, resulting in aggressive behaviour.
Describe the full process of how the limbic system causes aggression.
Amygdala –> Quickly evaluates the emotional importance if sensory information –> Assesses and responds to environmental things and challenges –> More likely to interpret the sensory information as a threat –> Reactivity increases accordingly –> Greater reactivity = aggression
Hippocampus –> Involved in the formation of long-term memories –> Allows current threat to be compared to similar past experiences (goes in-between assesses and more likely) (Impaired hippocampus means sensory information is not put into a meaningful context)
What is serotonin?
Serotonin is an inhibitory neurotransmitter – it slows down and dampens neuronal activity.
What is serotonin’s function (job)?
Normal levels of serotonin are linked with reduced firing of neurons, and so inhibit responses to emotional stimuli that might otherwise lead to an aggressive response.
Therefore normal levels of serotonin are associated with a greater degree of behavioural self-control.
Serotonin typically inhibits the firing of the amygdala. Low levels of serotonin remove this inhibitory effect.
Describe how serotonin levels are thought to lead to aggression and why this is the case.
Same as above but low levels of serotonin removes the inhibitory effect (lowering self-control)
The neural explanations of aggression are biologically determinist. How?
The neural explanations of aggression are determinist in that they see aggressive behaviour as governed by internal, biological causes that we have no control over [you need to give examples of how here]. This has implications for our legal system and wider society. One of the rules of law is that offenders (aggressive or otherwise) are seen as legally and morally responsible for their actions. The links between serotonin, the amygdala and aggression, could complicate this principle. Additionally, this may lead to screening of the population to identify this susceptibility and discrimination against those people.
Why is it a problem that neural explanations of aggression are biologically determinist?
This has ethical implications for people with the biological predisposition (as they may be monitored in their daily activities which breaches their right to privacy) as well as victims of crimes where criminals may not take responsibility for the crimes that they have committed. Whilst this doesn’t challenge the validity of the explanations, it may make the less palatable explanations of aggression.
Counterargument: However, other psychologists suggest that if individuals discover that they have a biological predisposition for aggression, this gives them the opportunity to avoid environmental situations likely to trigger this predisposition or develop coping skills that would protect them from their influence.
The neural explanations (particularly the serotonin explanation) are reductionist. How?
Ignore
The links between biological mechanisms such as serotonin and the amygdala are well established in non-human animals. However, the position is not quite so clear in the case of humans. This is not to deny that such links exist, but rather that the complexity of human social behaviour means that a biological explanation for aggression is insufficient on its own to explain all the many different aspects of aggressive and violent behaviour because it is reductionist. For example, Bandura’s study demonstrates that humans can learn aggression through social learning theory [you need to describe how here]
Why is this a problem? What evidence do we have to support that aggression is more complex?
Ignore
This suggests that the neural explanations are incomplete on their own to explain all instances of aggression and so they are not completely valid explanations of all aggressive behaviour.
Counterargument: however, such reductionism does enable cause and effect to be established between serotonin and aggression, which has the potential to lead to effective drug therapies to reduce aggression in society by altering serotonin levels.
Describe what Charles Whitman did and how his case supports the neural explanations of aggression.
In 1966, 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 tumour pressing against his amygdala.
This supports that the amygdala plays an important part in aggression in humans, with the tumour potentially making his amygdala more reactive triggering aggression, supporting the validity of the theory.
Why is Charles Whitman’s case not strong support for the neural explanations?
Charles Whitman also suffered childhood trauma (abuse from his father), was going through a number of stressful events (breakdown of his marriage and failing university) and he was raised in a home with guns (so could have learned aggressive behaviour). Therefore, the research can’t be taken as strong support for the internal validity of the theory as it isn’t possible to establish cause and effect between the amygdala and aggression.
Describe supporting evidence for the role of the limbic system. Explain exactly how it supports the limbic system leading to aggression.
Gospic et al. (2011) exposed some participants to mild provocation and their responses were recorded using an fMRI. When participants responded aggressively, the scans showed a fast and heightened response by the amygdala. They also found that a benzodiazepine drug (which reduces arousal of the autonomic nervous system) taken before the provocation had two effects - decreasing the activity of the amygdala and reducing the aggression (halving the rejections in the study).
This supports that there is a causal link between the amygdala and aggression, as when provoked, the amygdala showed greater reactivity and this was linked to aggressive responses, and when the amygdala reactivity was reduced, aggressive responses also decreased. Therefore this supports the internal validity of the limbic system as a causal factor in aggression.
Describe one study that supports or undermine the role of serotonin in leading to aggression. Explain exactly how it supports or undermines serotonin leading to aggression.
Berman et al. (2009) gave their participants either a placebo or a dose of paroxetine, a drug which enhances serotonin activity. Participants then took part in a laboratory-based game in which electric shocks of varying intensity were given and received in response to provocation. The paroxetine participants consistently gave fewer and less intense shocks than those in the placebo group. However, this was only true of participants who had a prior history of aggressive behaviour.
This supports that there is a causal link between serotonin and aggression in humans, as when serotonin levels were decreased, aggression increased and vice versa. Therefore this supports the internal validity of the role of serotonin levels impacting aggression.
Counterargument: however, this was only true in those who had a prior history of aggressive behaviour, suggesting that the theory may not be entirely valid on its own in explaining every instance of aggression (e.g. Where there is no prior history of aggressive behaviour).
What are hormonal mechanisms of aggression?
Chemical substances that circulate in the bloodstream that may be responsible for aggression.
What is testosterone?
The male sex hormone
How is testosterone linked to aggression? Including example study
It has a role in regulating social behaviour (including aggression) via its influence on certain areas of the brain implicated in aggression.
It is thought that higher levels of testosterone are related to aggressive behaviour.
For example, Dolan et al. (2001) found a positive correlation between testosterone levels and aggressive behaviours in a sample of 60 male offenders in UK maximum security hospitals.
What is progesterone?
Progesterone is a female ovarian hormone that is thought to play an important role in aggression in women.
How is progesterone linked to aggression?
Levels of progesterone vary during the ovulation cycle and are lowest during and just after menstruation.
Low levels of progesterone are linked to increased aggression in women.
Describe one study that supports testosterone being linked to aggression.
Dabbs et al. (1987) measured salivary testosterone in violent and non-violent criminals. Those with highest testosterone levels had a history of primarily violent crimes.
This supports that testosterone levels are linked with aggressive behaviour in humans, where higher levels are correlated with more aggressive behaviour, suggesting the explanation as some validity.
Counterargument: however, this is only a correlation, meaning that from the study we cannot strongly support the internal validity of the role of testosterone in aggression as we cannot determine cause and effect between testosterone levels and aggressive behaviour.
Explain one study that says that testosterone by itself does not cause aggression. What does it say leads to the aggression? What does this tell us about the theory?
There is mixed evidence of a link between testosterone and aggression in humans. Carre and Mehta (2011) developed a dual-hormone hypothesis to explain why. They claim that high levels of testosterone lead to aggressive behaviour, but only when cortisol levels (linked to stress) are low. When cortisol levels are high, testosterone’s influence on aggression is blocked. Therefore the combined activity of testosterone and cortisol may be a better predictor of aggression than either hormone alone and so the testosterone explanation may not be a completely valid explanation of aggression.
Describe one study that supports progesterone being linked to aggression.
Ziomkiewica et al. (2012) found a negative correlation between progesterone levels and self-reported aggression. This supports that progesterone levels are linked with aggressive behaviour in humans, where lower levels are correlated with more aggressive behaviour, suggesting the explanation as some validity.
Counterargument: however, this is only a correlation, meaning that from the study we cannot strongly support the internal validity of the role of progesterone in aggression as we cannot determine cause and effect between progesterone levels and aggressive behaviour.
When we say that aggression is genetic, what does this mean?
The propensity for aggressive behaviour lies in a person’s genetic make-up i.e. offspring inherit aggression from their parents via genes.
Describe the procedure and results of one twin or adoption study that suggests aggression is genetic. Explain how the results suggest aggression is genetic using the concordance rates and the % of genes the participants share.
Coccaro et al. (1997) :
They studied adult male monozygotic (MZ – identical) and dizygotic (DZ – non-identical) twins. For aggressive behaviour (defined as direct physical assault), the researchers found concordance rates of 50% for MZ twins and 19% for DZs. The corresponding figures for verbal aggression were 28% for MZ twins and 7% for DZ twins.
The results suggest that aggression is at least partly genetic because the concordance rate is higher for MZ twins than DZ twins and MZ twins have more genes in common than DZ twins. Therefore, the greater similarity in aggression could be inferred to be due to their greater genetic similarity.
Evaluation - environment must also play a role in aggression because the concordance rate for MZ twins who share 100% of their genes is not 100%.
Which gene is thought to play a role in aggression?
MAOA gene
How exactly is it thought that this gene leads to aggression? Mention which allele is involved and how this impacts the enzyme and therefore aggression.
Monoamine oxidase A (MAOA) is an enzyme which regulates the metabolism (breaking down of a neurotransmitter after a neural impulse has been transmitted from one neuron to another) of serotonin in the brain.
There is a gene responsible for producing this enzyme that has been associated with aggressive behaviour.
One low activity variant (allele) of the MAOA gene (nicknamed the ‘warrior gene’) leads to low MAOA activity in areas of the brain, and has been associated with various forms of aggressive behaviour.
Brunner et al. (1993) studied a Dutch family. What did they find. How does this support that aggression is genetic
Brunner et al. (1993) studied 28 members of a large Dutch family who were repeatedly involved in impulsively aggressive criminal behaviours such as rape, attempted murder and physical assault. They found that these men had abnormally low levels of MAOA in their brains and the low-activity version of the MAOA gene. It shows that the low levels of the gene cause aggression.
Explain one problem with using twin/adoption studies to support that aggression is genetic. What does this tell us about the theory if the studies aren’t well designed?
Twin and adoption studies make use of different research methods. Some use self-report techniques whilst others use observational techniques. For example, in the Miles and Carey (1997) meta-analysis, they found that genetic factors explained a large proportion of the variance in aggressive behaviour in studies that had used parental or self-reports. However, those that had made use of observational ratings showed significantly less genetic contribution and a greater influence of environmental factors.
These inconsistencies make it difficult to accurately assess the relative contributions of genetic and environmental influences on aggression. Therefore from the research is difficult to strongly support the role of genetic factors in aggression.
The genetic explanation of aggression is biologically determinist. What does this mean?
The genetic explanation of aggression is determinist in that it sees aggressive behaviour as governed by internal, biological causes that we have no control over (i.e. We have no free will over our behaviour). This has implications for our legal system and wider society. One of the rules of law is that offenders (aggressive or otherwise) are seen as legally and morally responsible for their actions. The links between genes and aggression could complicate this principle. Some legal experts now question the assumption that a violent offender can exercise their free will when they have a genetic predisposition to violent crime i.e. the research could be used as evidence of a defendant’s diminished responsibility. Such a change may force us to revise our notions of moral and legal responsibility based on the findings of the research. Additionally, this may lead to genetic screening of the population to identify this susceptibility and discrimination against those people. This makes an awareness of the limitations of genetic research extremely important.
Why is this a problem? Include both the legal system and ethical implications for those who are identified as being genetically at risk.
This has ethical implications for people with the genetic predisposition (as they may be monitored in their daily activities which breaches their right to privacy) as well as victims of crimes where criminals may not take responsibility for the crimes that they have committed and so it may not be a palatable explanation of aggression. It appears that we should apply the theory with caution as currently there are so many flaws with the research, that it cannot be confidently concluded that genetics plays the greatest role in the determination of aggressive behaviour.
Counterargument: However, other psychologists suggest that if individuals discover that they have a genetic predisposition for aggression, this gives them the opportunity to avoid environmental situations likely to trigger this predisposition or develop coping skills that would protect them from their influence.
What evidence do we have that genes alone poorly predict behaviour and therefore being determinist is a significant issue?
Ignore
Morley and Hall (2003) argue that genes associated with aggression are deterministic and only poorly predict the likelihood that an individual will display higher levels of aggressive behaviour. Additionally, the presence or absence of environmental risk factors cannot be identified using a genetic test, making the accurate prediction of specific behaviours even less likely. This is supported by Caspi et al.’s study.
How can the MAOA gene explain why men are more aggressive than women? Why is this a strength?
Ignore
The MAOA gene research offers an explanation for the uneven rates of aggression and violence for males and females. Niehoff (2014) suggests that this may be due to the different genetic vulnerabilities that males and females have to the MAOA gene. The MAOA gene is linked to the X chromosome. Women have two X chromosomes, whereas men only have one. When men inherit an X-linked gene from their mothers, they are more likely to be affected by it, whereas women inheriting the same gene are generally unaffected (as they also have the a second X chromosome with a ‘normal’ gene for MAOA that prevents expression of the abnormal version of the gene).
This could explain why males typically show more aggressive behaviour than females and so gives us more confidence in the validity of the explanation of aggression as it can explain real differences in rates of aggression.
Describe evidence other than Brunner et al. That supports that the MAOA gene leads to aggression. Explain how it supports the exact proposals of the theory.
Mertins et al. (2011) studied participants with low-activity and high-activity variants of the MAOA gene in a money-distributing game. Participants had to make decisions about whether or not to contribute money for the good of the group. The researchers found that males with the high-activity variant were more cooperative and made fewer aggressive moves than the low-activity participants.
This supports the importance of the MAOA gene in aggressive behaviour. It suggests that possession of the high-activity variant leads to the exact opposite behaviour (cooperation) to that associated with the low-activity variant (aggression). The two predictions of the MAOA explanation are opposite sides of the same coin. As both are confirmed by research evidence, this increases our confidence that the genetic explanation is a valid account of how genes influence aggressive behaviour.
What is ethology?
Ethology is the study of animal behaviour in natural settings. The findings are then extrapolated to humans because we are all subject to the same forces of natural selection.
According to the ethological explanation of aggression, how is aggression caused?
Ethological explanations suggest that aggression is an innate behaviour (instinct) that is mostly genetically determined.
When we say that aggression is adaptive, what do we mean?
Therefore, it is suggested that aggression is adaptive i.e. it is beneficial for survival, and therefore the animal is alive to reproduce.
How does aggression therefore get passed down?
The aggression is then passed down to the offspring via natural selection.
What is ritualistic aggression?
Ritualistic aggression is a series of aggressive behaviours carried out in a set order.
What is a threat display and how is this aggression adaptive? And how does it get passed down?
Lorenz noted that fights between conspecifics involve very little physical damage. Instead, most aggressive encounters consisted of a period of ritualistic signalling in the form of threat displays. E.g. baring claws and teeth, beating chest etc. Such aggression is adaptive because it enables competitors to assess their relative strength before deciding to escalate a conflict. They are intended to intimidate an opponent and make them back down. This makes costly and dangerous physical aggression less likely to occur ensuring the survival of the species.
They survive and then pass genes down via natural selection
What is a ritual appeasement display and how is this adaptive? And how does this get passed down?
Lorenz pointed out that aggression between conspecifics end with ritual appeasement displays which indicate acceptance of defeat e.g. wolves exposing their jugulars. This is adaptive because in signalling defeat, it inhibits further aggression by the victor, preventing further damage or death of the loser, again ensuring the survival of the species.
They survive and then pass genes down via natural selection
How is being aggressive (fighting) adaptive? Explain the two ways, making sure to include how the aggression therefore gets passed down.
One adaptive function of aggression is to establish domin0ance hierarchies with the winners of conflicts climbing the social hierarchy. This increased status leads to other benefits such as access to mates. Therefore aggression is adaptive because dominance over others brings benefits such as access to resources (aiding survival) and mates (reproduction – so aggression is naturally selected).
Aggression is also beneficial to survival because a defeated animal is rarely killed. Instead, they are forced to establish territory elsewhere. Therefore, individuals that win conflicts have greater access to resources as there is less direct competition for things such as food. As such, aggression is adaptive in that it aids survival and so is naturally selected. It also has the added benefit of spreading the members of a species out over a wider area, reducing the possibility of starvation for all.
What is an innate releasing mechanism?
Innate releasing mechanisms are a key part of the ethological explanation of aggression. They are hard-wired networks of neurons in the brain that respond to an environmental stimulus (a sign or releaser such as a facial expression) by initiating a fixed action pattern.
What is a fixed action pattern?
A fixed action pattern is a set sequence of behaviours (in this case, aggression). These behaviours are stereotyped to occur only in specific conditions and do not require learning (i.e. they are innate).
Name and define the six characteristics of fixed action patterns
- They are stereotyped – they are relatively unchanging sequences of behaviours
- They are universal – the same behaviour is found in every individual of a species.
- They are unaffected by learning – they are the same for every individual regardless of experience.
- They are ‘ballistic’ – once the behaviour is triggered, it follows an inevitable course and cannot be altered before it is completed.
- They are single-purpose – the behaviour only occurs in a specific situation and not in any other.
- They are a response to an identifiable specific sign stimulus (or if it involves communication between members of the same species, it is known as a releaser).
What is an environmental stimulus?
A sign or releaser triggers
How are fixed action patterns triggered?
Environmental stimulus (a sign or releaser triggers) –> Innate releasing mechanism (hard wired set of neurones in brain that responds to this by triggering…) –> Fixed action pattern (a set sequence of behaviours - aggression)
Describe Tinbergen’s procedure and findings. Make sure to identify what the environmental stimulus, innate releasing mechanisms and fixed action pattern were.
Ignore
Identify the environmental stimulus.
Red underbelly of the stickleback fish
What is the fixed action pattern that occurs?
Aggression - attacks the other stickleback fish (head butts)
Explain how the fixed action pattern shown by the stickleback matches the characteristics of FAPs.
- They are stereotyped – they are relatively unchanging sequences of behaviours - head butts the other fish until it leaves
- They are universal – the same behaviour is found in every individual of a species. - this happens in every male stickleback fish
- They are unaffected by learning – they are the same for every individual regardless of experience. - they will always attack a fish with a red underbelly no matter what they’re taught
- They are ‘ballistic’ – once the behaviour is triggered, it follows an inevitable course and cannot be altered before it is completed. Male stickleback fish will continue to attack the other fish until the fish leaves (can’t be altered or stopped before it’s finished)
- They are single-purpose – the behaviour only occurs in a specific situation and not in any other. When it sees the red underbelly of the other fish
- They are a response to an identifiable specific sign stimulus (or if it involves communication between members of the same species, it is known as a releaser). - When it sees the red underbelly of the other fish
Based on the theory, what occurs between the environmental stimulus and FAP?
Innate releasing mechanism - hard wired set of neurons that respond to the red underbelly (environmental stimulus) by triggering the aggression (fixed action pattern)
Male sticklebacks are highly territorial during mating season, where they also develop a red spot on their underbelly. If another male enters their territory, a fixed action pattern is initiated. The sign stimulus that triggers the innate releasing mechanism is the sight of the red spot.
Tinbergen presented sticklebacks with a series of wooden models of different shapes, some with red spots on their underbelly and some without.
Regardless of shape, if the model had a red spot the stickleback would aggressively display and even attack it. But if there was no red spot, there was no aggression, even if the model looked realistically like a stickleback.
Tinbergen also found that these aggressive FAPs were unchanging from one encounter to another, and once triggered they always ran their course to completion.
How does Brunner et al.’s study support the ethological explanation?
Ignore
There is lots of evidence to support the ethological explanation. For example, Brunner et al. (1993) found that the low-activity variant of the MAOA gene is closely associated with aggressive behaviours, suggesting an innate basis. Additionally, research on the relationship between the limbic system and aggression provides evidence for the existence of innate releasing mechanisms for aggression in the brain in humans and other animals. This supports the validity of the ethological explanation of aggression as the evidence supports its suggestion that aggression is genetically determined, heritable and adaptive [you need to explain how for the study that you have chosen].
What evidence is there to support that ritualistic aggression occurs in humans? How does this therefore support the ethological explanation?
Anthropological evidence suggests that the benefits of ritualistic aggression are also present in human cultures. For example, Hoebel (1967) found that among Inuit Eskimos, song duels are used to settle grudges and disputes. This supports that rituals have the effect of reducing actual aggression and preventing injury or death of the combatants as predicted by the ethological explanation, supporting that the results from animals may be generalisable to humans as we are subject to the same forces of natural selection.
Goodall (2010) observed chimpanzees during a four year war. What did they find and how does this undermine the ethological explanation?
Goodall (2010) observed chimpanzees at the Gombe Stream National Park in Tanzania. During the ‘four year war’, male chimps from one community set about systematically slaughtering all members of another group. They did this in a coordinated and predetermined fashion. On some occasions, a victim was held down by some rival chimpanzees while others hit it and bit it in an attack lasting up to 20 minutes. The violence continued like this despite the fact that victims were offering signals of appeasement and defencelessness. In other species such as lions, males will often kill off the cubs of other males, and male chimpanzees will routinely kill members of their group.
The appeasement signals did not inhibit the aggressive behaviour of the attacking chimpanzees as predicted by the ethological explanation and cast doubt on the claim that much of animal aggression is ritualistic rather than real. Additionally, the killing was systematic rather than accidental which goes against the prediction that a defeated animal is ‘rarely’ killed in order to ensure the survival of the wider species and spread the species out over a wider area to reduce competition pressure for resources. Therefore, this calls into question the validity of the ethological explanation as an explanation of aggression.
