Assess the Role of Neurons and Hormones in Aggression. (16 Marks)

The idea that aggression is caused by hormones and their effect on the brain has a lot of research to support it. Such as research by Linnoila who found a relationship between low levels of serotonin being produced and highly violent behaviours, this proves that a reduction in serotonin is linked to aggression. Also, Connor who found rats that had been castrated at birth had less aggression when adults, proving that there is a link between aggression and testosterone. The last research to support the role of hormones and neurons is known as the spicy study, in this study male participants were given a drink with chilli sauce in and either assembled a gun or the game mousetrap. They were then allowed to prepare a drink for the next participant with as much chilli sauce in as they liked. They found that the men building guns put more chilli sauce in the drinks that then men building the board game. This study proves to us that when we are in situations that are testosterone levels increase, we are more likely to act aggressively.

Although there is this research support, it does have disadvantages. Connor used animals in his research which means it has extrapolation issues because humans are very different to animals as we have cognitions, opinions, ideas, etc. because of this, we cannot generalise the results to humans. This study also lacks internal validity because we may not be testing what we actually want to be testing as castration would affect many chemicals in the body not just testosterone. Linnoila used correlational research which means we cannot establish cause and effect, so the how levels of serotonin could cause violent behaviour or violent behaviour could cause low levels of serotonin, making the research bi-directional. Sapolsky also says the theory is bi-directional as he believes high levels of testosterone do not lead to heightened levels of aggression but aggressive behaviour raises testosterone, challenging the clarity of the biological theory....