- Biological explanations view aggression to be caused from internal physiological changes.
- Testosterone is a male hormone which is also found in low levels in females that is associated with aggression.
- It is seen to be influential in two time periods: Critical time period, a few days after birth, and adulthood when it is modulated to the neurotransmitter pathways.
- Testtosterone acts on the serotonergic synapses, lowering the amount of serotonin which is seen to be associated with heightened aggression.
- Connor and Levine castrated rats after birth and found reduced aggression when tested as adults however those castrated after puberty could be made aggressive with testosterone injections suggesting it may be a developmental factor.
- Higley reported that individuals with raised levels of testosterone exhibit signs of aggression but rarely commit aggressive acts suggesting that social and cognitive factors play a mediating role.
- Most research into testosterone comes from animal studies showing generalisation issues as human aggression is much more complex involving previous experience and environmental stimuli.
- There are methodological issues with…