Biological theory of aggression – role of hormone testosterone

What is a hormone?

Chemical messengers that transmits information around body through bloodstream.

Involved in regulating physiology and behaviour including breathing, temperature.

Produced and excreted by glands in this system of glands is called the endocrine system

What is the effect on behaviour of testosterone?

Causes aggression and anger, primary male sex hormone

What is the effect on behaviour of adrenaline?

Exhilarating and exciting, makes us more alert fight or flight response

What is the effect on behaviour of serotonin?

Increases happiness, regulate mood

What is the effect on behaviour of oestrogen?

Affect aggressive behaviour, female sex woman

What are the effects on behaviour of cortisol?

Linked to metabolism in blood pressure

How has testosterone been linked to aggressive behaviour?

• Testosterone is an androgen – chemical that develops male characteristics

• Antenatal exposure to testosterone has an organising effect on developing brain, leading to an increased spatial awareness and competitive aggression

• During critical period immediately following birth, testosterone sensitises certain neural circuits. Stimulates cell growth in areas of hypothalamus and amygdala which, has role in perception and reaction to environmental threat, includes aggressive responses.

What is the evidence for this an animal experiments?

• Male rodents castrated – stopped production of testosterone - Behaviour is compared to control rodents

• Castrated rodent so very little aggression – but if testosterone is replaced by injection they show typical aggressive behaviour

• Neonatal Female rodents injected with testosterone act more aggressive then adult adults compared to control females

What are the three pieces of evidence That use human participants

Mazur, Hawke, Dabbs et. al.

For Hawke what did they do?

What did they find?

What was the conclusion?

Evaluative AO3 comment

Hawke looked at case studies of convicted sex offenders who had Ben castrated.

There have been cases where Convicted sex offenders have been chemically castrated and this led to the removal of aggression and the loss of sex drive.

This suggests testosterone may be causing aggression in these individuals

There was a lack of control group

What does adrenaline do?

Hormone in adrenal gland make helps you prepare for stressful dangerous situations. Adrenaline rush is the name for the quick release of adrenaline into bloodstream, gets ready for fight or flight response

Evaluation of hormones as an explanation for aggression

…

Evidence

🙂- Wide variety of evidence – correlations, animal studies, human studies

Animal studies – chemical castration of rodents reduces aggression injection with testosterone increase levels of aggression

Hawke- Sex offender castration counter argument- No control group

Strengths/shortcomings

😔– Reductionist – assumes aggression can be broken down to hormones and doesn’t take into account other factors

😔– Testosterone explanations do not assess role of hormone in different types of aggression