hormonal influence

• observations of behaviour across many species reveals that aggression occurs more in male than females
• what is testosterone

  one of a class of male hormones called androgens

  • important in producing sperm and developing secondary sexual characteristics

  they have an influence on a range of behaviours - including aggression
• research has shown that aggression increases with increased levels of T in puberty
• animal research has show that when animals (mice) are castrated, aggression decreases
• role of testosterone 


  the role of testosterone in aggression is clear in the behaviour of lower order animals, but there is strong evidence that it contributes to human aggression too
• taking androgens


  for ethical reasons androgens cant be given to humans to see if changes in aggression occurs because they would need to be taken over a period of time which has a health risk
• Dabbs 


  investigated the relationship between T, crime and prison behaviour

  measured T level in saliva of 692 adult male prisoners

  • found a positive relationship between the levels of violence in a crime and levels of T
  • those who committed crimes with sex and violence had higher T kevels that inmates who committed crimes like burglary and theft
  • high testosterone males also broke more prison rules involving confrontation
• criticism of research 


  androcentric - most of Dabbs work is carried out on males

  women have less T than men but its effects are considered to be the same

  but Dabba=s looked at criminal history and T levels of 84 female prison inmates

  • found that T levels were related to criminal violence - but relationship not as straight forward
  • T was highest in case of unprovoked violence but lowest where violence was defensive
• criticism 


  research is correlational - problem with bi-directional ambiguity

  • rather than T causing aggression , could be that aggressive behaviour causes T to increase
  • some evidence where this is the case - research has shown that with animals during status conflicts T rises in winner and declines in the losers - T not only effects behaviour but also responds to it
• criticism 


  deterministic

  argues that aggression is determined by levels of hormones

  • socially sensitive
  • as its led some to suggest the use of chemical castration to reduce aggression but there could be other factors causing the aggression
• criticism 


  reductionist

  research is reductionist as the hormones explanation reduces complex human behaviour of aggression down to high levels of T

  • theory emphasises the role of nature but its likely there are many other reasons for aggression - SLT
  • SLT states that aggression can be learnt due to our environment , arguing for role of nurture
  • likely to be a combination of vulnerability and environmental trigger = diathesis-stress