Hormones (testosterone) - radke + goetz

horomone

• chemical messenger

• secreted by glands in endocrine system

• released directly to the blood stream

• stimulate parts of the body (physiological responses and brain activity)

• take longer to feel effects compared to neurotransmitters

Testosterone

• produced by testies and ovaries

• correlated with aggression

• higher in males than females

Aim of Goetz

To examine the effects of testosterone on the activity/reactivity of the amygdala which is the part of the brain associated with emotional response and aggression levels through the stress response (fight or flight)

Method of Goetz

• 16 healthy young men tested on over two days

• repeated measures design (pp do both conditions)

• pp tested at start to ensure same levels of testosterone

• two conditions, dose of testosterone and placebo

• pp placed in fmri to measure brain activity when seeing faces with different emotions

Results of Goetz

Significant activation of the amygdala in testosterone condition when pp saw angry faces, but not with neutral faces

Conclusion of Goetz

Testosterone influences the reactivity of the amygdala because the control with elevated testosterone had higher activation of the amygdala compared to placebo control

eval of goetz

• repeated measures design which reduces pp variability and increases internal validity

• sample of strong, healthy men which shows signs of high testosterone

• pp placed in fMRI which could cause stress due to loud and small space which could induce claustrophobia

aim of radke

to investigate the relationship between perceiving a social threat, testosterone, and the amygdala

method of radke

• 54 healthy female participants

• half given testosterone 

• half given placebo

• participants shown happy or angry faces in fMRI

• researcher then instructs them to either approach faces or avoid faces with joystick

results of radke

• fMRI measured the activity in the amygdala and prefrontal cortices

• the testosterone group had greater activation in the amygdala when approaching angry faces compared to control group

conclusion of radke

• in conclusion,  the level of testosterone affected the activity of the amygdala in a situation where there is motivation to defend against a threat, because the group with higher levels of testosterone showed increased amygdala activity in comparison to the control group while viewing an angry face.

eval of radke

• pp given a pill of testosterone which could cause harm to participants as they could react badly to it

• pp placed in fMRI which could cause stress due to loud and small space which could induce claustrophobia

• used a control which allows for a comparison to be made which increases the validity of the results