Neural and Hormonal in Aggression Flashcards
What is included in the limbic system?
Hypothalamus, fornix, amygdala and cingulate gyrus.
How does the limbic system relate to aggression?
Speed and sensitivity of limbic system responses to stimuli are important predictors of aggressive behaviour in humans.
Which area of the limbic system is most strongly associated with aggression? Why?
Amygdala. This plays a key role in how we assess and respond to environmental threats.
Outline the study that links aggression to the amygdala in the limbic system.
Gospic et al Carrie don’t fMRI on pps in a lab based game that provoked aggression.
These scans showed aggressive reactions were associated with a fast and heightened response by the amygdala.
Benzodiazepine (reduces arousal of the ANS) taken before games 1/2d the number if aggressive reactions and decreased amygdala activity.
How does serotonin link to aggression?
Decreased serotonin disturbs the inhibitory mechanism in the orbitofrontal cortex and increases impulsive behaviour eg aggression.
Outline the study into the relationship between serotonin and aggression. (Virkkunen et al).
Virkkunen et al compared levels of serotonin metabolite (breakdown byproduct) in the cerebrospinal fluid of violent impulsive and non-impulsive offenders.
Levels were significantly lower in violent offenders (so disturbance of this pattern implies disruption of serotonin functioning).
How can the hormonal mechanism explain why males are more violent?
Because testosterone (which helps to regulate social behaviour via influence on areas of the brain involved in aggression) is higher in men.
Outline the study that shows the role of testosterone in aggression.
Dolan et all found a +ve correlation between testosterone levels and aggressive behaviours in male offenders in U.K. maximum security prisons.
How have animal studies been used to show aggression?
Animal studies (Guammanco et al) show experimental increases in testosterone are related to aggressive behaviour.
The converse is also true - testosterone decrease leads to reduction in aggression in castration studies).
