AO1

• testosterone - at 3mths foetuses produce testosterone in testes if they are male showing it stimulates development of male sex organs 
• testosterone is associated with aggression and competitiveness
• testosterone is linked to the masculinisation of the brain eg spacial skills
• Dabbs et al investigated link between 692 prisoner’s beh and testosterone levels, and found higher testosterone levels more likely committed crimes involving sex and violence. It was also found that lower testosterone levels more likely committed crimes of burglary suggesting presence of testosterone causes heightened arousal and aggressive behaviour 
• Oestrogen controls onset of mensturation and foetal development when pregnant
• Oestrogen has feminising effects on brain development