Neural and hormonal mechanisms in aggression Flashcards
Neurotransmitters:
What are neurotransmitters?
chemicals that enable impulses within the brain to be transmitted from one area to another.
Neurotransmitters:
What levels of serotonin and dopamine have been associated with aggression??
Low levels of serotonin
High levels of dopamine
Neurotransmitters:
How does serotonin cause aggressive behaviour?
It inhibits the responses to stimuli that might otherwise lead to aggressive behaviour reducing the chance of aggressive behaviour. Low levels of serotonin have been associated with an increased susceptibility to impulsive and aggressive behaviour. Drugs that deplete serotonin have been shown to increase aggression in participants.
Neurotransmitters:
How does dopamine cause aggressive behaviour?
Increases in dopamine activity has been shown to produce increases in aggressive behaviour. Drugs that increase dopamine activity in the brain have been showed to increase levels of aggressive behaviour.
Neurotransmitters:
Serotonin- there is research support for low levels of serotonin causing aggressive behaviour
Giving participants a drug known to deplete serotonin, questionnaires were also given to assess hostility and aggression levels, they found the drug, in males only, increased aggression score.
Neurotransmitters:
Serotonin has research support from animal studies
Monkeys fed on food which increase levels of serotonin, showed decreased levels of aggression and visa versa.
Neurotransmitters:
Serotonin also has support from antidepressants
Drugs that deplete serotonin levels lead to increased aggressive levels then visa versa is true and this ids actually what happened in clinical studies using antidepressant drugs
Neurotransmitters:
Dopamine- it’s influence might be a consequence rather than causal
In mice, a reward pathway in the brain becomes engaged in response to an aggressive event and that dopamine is involved as a positive reinforcer in this pathway. Suggesting that individuals will seek out an aggressive encounter because of the rewarding sensation they get from it
Hormonal:
Testosterone-
Testosterone is thought to increase aggressive behaviour in adults due to it’s action on the brain. Research has found that criminals with the highest levels of testosterone had a history of mainly violent offences.
Hormonal:
Testosterone- What’s the challenge hypothesis?
Testosterone should only rise above baseline levels in response to social challenged e.g threat to status.
Hormonal:
Testosterone- Many of this research is actually inconsistent
Studies have found no relationship between testosterone and aggression. Plus, those studies that have found a relationship, are conducted on small samples and rely on self-report questionnaires which leads to reduced reliability.
Hormonal:
Testosterone- This research is beta-bias
It focuses on mainly men, yet the research suggests that the link between testosterone and aggression is stronger for women, with them becoming more assertive, testosterone is shown as women become more successful.
Hormonal:
Testosterone-There is a difference between aggression and dominance and we should make this difference clear
People act aggressively when they want to cause harm whereas people act dominantly when they want to maintain status. The influence of testosterone on dominance is likely to be expressed in more varied and subtle ways rather than aggressive behaviour.
Hormonal:
Testosterone- How does the real world application support the challenge hypothesis?
The presence of a stimuli e.gun triggers an increase in testosterone levels which increases aggression, a chain of events that would be predicted by the Challenge hypthothesis.
Hormonal:
Cortisol:
Cortisol is thought to increase anxiety.
High levels of cortisol inhibit testosterone and so inhibit aggression. High testosterone is the primarily biochemical influence on aggression, low cortisol plays an important role in increasing the likeliness of aggressive behaviour.
