Structure of the brain and aggression Flashcards
What is aggression?
Behaviour that is intended to cause injury. In humans, this could be psychological as well as physical injury. In animals, aggression is often is often directed at establishing and maintaining dominance or acquiring resources. Aggression is often expressed in ritualised form to prevent actual physical harm.
What is the key structure in the limbic system that causes aggression?
The amygdala
What is the central role in the amygdala?
In how an organism assesses and respons to environmental threats and challenges. The reactivity of the amygdala in humans is proven to be an important predictor of aggressive behaviour
What type of people did Emil Coccari study?
People with (IED) intermittent explosive disorder.
What did they discover in the fMRI scans after showing the IED pictures of angry photos?
There were high levels of amygdala activity - not in the control IED group
Why are the pictures of angry faces good?
As it is an ecologically valid sign of threat
What does the amygdala function in tandem with?
The prefrontal cortex- more specifically the orbitofrontal cortex (OFX)
What role does the OFC play?
It is involved in self- control, impulse regulation and inhibition of aggressive behaviours. Patients in psychiatric disorders that feature aggression often have lower activity in the OFC.
What is the role of serotonin?
Is a neurotransmitter with widespread inhibitory effects on transmission between neurons in the brain
It slows down and dampens neuronal activity
What is the normal behaviour to decreased serotonin in the PFC?
Reduced self control and lead to more impulsive behaviour inlcuding aggression
What did Virkkunen discover about levels of serotonin in violent impulse offenders?
Significantly lower in impulse offenders who also suffered from more sleep irregularities.
Serotonin helps to regulate sleep 5 disturbance of sleep strongly imlpies some disruption of serotnin functioning.
