Hi if someone could give feedback on this it would be appreciated.
Question: Describe and evaluate the one or more of the following biological explanations for human aggression: neural, hormonal, genetic.
One hormonal explanation of aggression is that human aggression is controlled by testosterone levels in the body. High testosterone levels have been found to be related with aggression in men. Take for instance, Wagner (1979) found that when mice were castrated (had their testes removed) their levels of aggression decreased. This suggests that testosterone is implicated in aggression. However, this study is an animal study and it is therefore difficult to generalize it to human beings. This is because animals have a different physiology to us and so therefore processes that occur in rats may not apply to human beings.
Another biological explanation of aggression is that aggression is caused by a faulty MAOA gene. The MAOA gene produces the enzyme that mops up left over neurotransmitters e.g., dopamine and serotonin and also breaks them down. It has been found that a low activity MAOA gene can be implicated in aggression. Caspi (2002) found that 85% of males with a low activity MAOA gene and experienced some form of childhood maltreatment developed antisocial behaviors. They also found that males with high MAOA activity did not develop antisocial behaviors even when they experienced some form of childhood maltreatment. This would suggests that aggression does have a genetic component and can therefore be predicted in individuals.
In addition to this, one biological explanation of aggression is that it is regulated by the limbic system. The limbic system is thought to be involved in our behavioral or emotional responses, especially those needed for survival e.g., the fight or flight response. The amygdala, which is found in the limbic system, is thought to be the emotional processing center in humans for aggressive drives. Wong et al conducted an experiment that included doing an MRI of 19 violent male criminals and then compared this to 20 'normal' control participants. He found that the amygdala volume of the criminals was significantly smaller than the amygdala volume of the control group 'normal participants.' This would suggest that the amygdala in the limbic system does play a role in the incidence of aggression. However, the validity of this research could be questioned because it may suffer from gender bias. Only male participants were used in the experiment so it could be argued that the results of this experiment that the results of the experiment cannot be generalized to women and therefore it suffers from beta bias.
Finally, another explanation of aggression is the neurotransmitter serotonin. It has been proposed that low levels of serotonin in the brain causes aggression. Mann et al investigated this by administering a drug that reduced serotonin levels to 35 healthy adults. The researchers then used a questionnaire to assess aggression in the participants after administering the drugs. The results of the study found that levels of aggression in males increased after administering the drug but did not increase in women. This would suggests that serotonin is a component that plays a role in the incidence of aggression but this conclusion cannot be applied to women as the results of this experiments suggest otherwise. This research demonstrates the issue of beta bias in the research of aggression. Females and males may not be subject to the same physiological factors when explaining aggression.