neuronal mechanisms in aggression Flashcards
What is the limbic system
Subcortical structures in the brain thought to be closely involved in regulating emotional behaviour including aggression
Who thought the limbic system is linked to emotional behaviours
James Papez (1937) and Paul Maclean (1952)
What structures are in the limbic system
Hypothalumus , amygdala, cingulate gyrus , thalamus,fornix , hippocampus
What role does the amygdala have in aggression
-The reactivity of the amygdala is an important predictor of aggressive behaviour ( in humans and mammals )
-The more responsive the amygdala the more aggressive a person is
Who did the study on the amygdala
Katarina Gospic et al . (2011)
Procedure and findings of study
Some ppt were subjected to mild provocation ; when ppt reacted aggressively FMRI scans showed a heightened and fast response by amygdala
-Benxodiazepine drug (slows down arousal) taken before provocation led to decreased activity of amygdala and half the no . of rejections
What is serotonin ?
Serotonin is a neurotransmitter that has a widespread inhibitory effect in the brain ie. slows down and calms neuronal activity.
How are serotonin and the OFC linked?
Normal levels of serotonin are linked with reduced firing of neurones which is associated with greater behavioural self-control
How is decreased levels of serotonin linked with aggression?
Decreased levels of serotonin disrupts the mechanism, reducing self control and increasing impulsive behaviour ; aggression (denson et al . 2012)
Study on offender :
Matti Virkkunen et al (1944) ;
compared levels of serotonin breakdown product (5-hIAA) in cerebrospinal fluid of violent impulsive offenders and non violent impulsive offenders.
The levels were significatly lower in impulsive offenders
