Neuronal and hormonal mechanisms Flashcards
What is the limbic system?
A group of interconnected brain structures that help regulate your emotions and behaviour
What structures make up the limbic system?
The hypothalamus
Amygdala
Parts of the hippocampus.
What role does the amygdala play in aggression?
The amygdala assesses and responds to threats. Increased amygdala activity is linked to higher aggression.
Who linked the limbic system to emotional behavior?
Papez and MacLean
What did Gospic et al. investigate?
They studied brain activity in aggression using fMRI scans during a provocation experiment.
What did fMRI scans show in aggressive participants?
A fast and heightened response in the amygdala.
What did the benzodiazepine drug that was given before the provocation do in Gossip et al’s investigation?
Reduced arousal of the autonomic nervous system.
What were the two effect of the benzodiazepine drug?
Decreased the activity of the amygdala Halved the number of rejections.
What did Gossip et al investigation illustrate?
the role of the amygdala in aggression
What is serotonin?
inhibitory neurotransmitter that helps with self control
What does it mean if you have normal levels of serotonin in the orbitofrontal cortex?
Linked with reduced firing of neurons
Associated with greater behavioural self-control.
Make us feel relaxed.
What does it mean if you have decreased levels of serotonin in the orbitofrontal cortex?
Disrupts mechanism
Reducing self-control
Leading to an increase in impulsive behaviour
Denson et al
What did Virkkunen et al. compare?
Compared levels of serotonin breakdown product in cerebrospinal fluid of violent impulsive and violent non-impulsive offenders.
What did Virkkunen et al find about serotonin levels in impulsive offenders ?
Lower serotonin levels in impulsive violent offenders
What is testosterone?
Testosterone is an androgen
Responsible for the development of masculine features.
What did Daly & Wilson find about testosterone and aggression?
Men are generally more aggressive than women, with higher aggression levels after age 20, when testosterone peaks.
What effect does castration have on aggression in animals?
Removing the testes leads to a reduction in aggression.
What happens when testosterone is injected back?
Aggression returns, confirming testosterone’s role in aggression.
What did they find?
A positive correlation between testosterone levels and aggression.
What is progesterone?
Progesterone is a female ovarian hormone.
how does progesterone relate to aggression?
Low progesterone levels lead to an increase in aggression.
What did Ziomkiewicz et al. find about progesterone and aggression?
Found a negative correlation between progesterone levels and self-reported aggression
