Hormonal Mechanisms - Studies

Dabbs et al (1987)

Measured salivary testosterone in violent and non-violent criminals. Violent criminals had higher levels of testosterone. 

Lindman et al (1987) 

Young males who behaved aggressively when drunk had high testosterone levels. 

The challenge hypothesis (Wingfield et al, 1990) 

In monogamous species, testosterone levels should only rise above baseline levels in response to social challenges. Males are expected to increase testosterone upon male-male conflict or 
reproductive success. 


Kouri et al (1995)

Procedure
- Double-blind procedure using young men.
- Given either testosterone or placebo.
- Paired with fictitious participant and told that each member of the pair could reduce the amount of cash the other received by pushing a button.
- Also told that the other participant was reducing the cash that the participant was receiving.

Findings
- Participants who received testosterone rather than the placebo pushed the button significantly more times.

Olweus et al (1980) 

Procedure
- Measured blood testosterone levels in 16-year-old boys.
- Assessed aggression using a questionnaire.

Findings
- Higher levels of self-reported physical verbal aggression were associated with higher levels of testosterone.

Baucom et al (1995)

Women with higher testosterone levels has higher occupational status, possibly as a result of  assertiveness. 

Albert et al (1993)

Despite many studies showing a positive correlation between aggression and testosterone levels, other studies find no such relationship and most studies showing a positive correlation involved small samples of men in prisons using self-reports of judgements on severity of the crime. 

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Van Goozen (2007)

Thers is a link between aggression and cortisol. 

Virkkunen (1985)

Low levels of cortisol in habitually violent offenders. 

Tennes and Kreve (1985)

There are low levels of cortisol in aggressive schoolchildren. 

McBurnett et al (2000) 

Procedure

- Evaluated 38 boys aged 7 to 12 for problem behaviour.
- Behaviours evaluated annually for four years.
- Salivary cortisol measurements taken during second and fourth years.

Findings 

- Boys with lower cortisol levels exhibited three time the number of aggressive symptoms compared to boys with higher levels of cortisol.
- Boys with low cortisol were also named the most aggressive and 'meanest' by peers.

Gerra et al (1997) 

Procedure

- Actually reported high cortisol = higher aggression.