Biological Aggression

Biological Aggression

1. Neural

   • dopamine
     • increase maybe=aggression
     • may be rewarding
       • so seek out aggressive encounters
         • produces dopamine
     • difficult to establish link
     • dopamine antagonists reduce dopamine
       • reduce aggressive behaviour
     • turn off dopamine in mice
   • seratonin
     • decrease=aggression
     • dexfenfluramine depletes
     • seratonin metabolism
       • not levels
       • increaced receptors
         • more violent suicide
     • low amounts of waste product in aggressive people
   • rat fight every day for 10 days
     • Ferrari et al

2. Hormonal

   • tesosterone
     • dominance link
     • makes aggression more likely
       • inconsistant evidence
     • challenge hypothesis
       • testosterone rises in social situations
     • +in older people
       • 208 men
       • enhance vigor and energy
     • gender bias
     • Book et al
       • meta analysis
     • no sd between violent and non violent offenders
   • cortisol
     • lower levels=highter levels of aggression
       • violent offenders
     • may inhibit aggression
     • inconsistant evidence

3. Genetic

   • MAOA
     • warrior gene
     • breaks down serotonin and dopamine
       • Brunner
         • men with defect gene
           • family history of aggression
             • tested urine
               • lots of neurotransmitter
               • not much MAOA waste
             • environmental factors?
   • twin+adoption studys
     • feelings of abandonment
     • + offender treatment
   • 40%
   • difficult to seporate nature and nurture
     • MZ twins
     • gene and environment interaction
   • 87% MZ
     • treated as one
   • 72% DZ
   • measure antisocial behaviour
     • not aggression
   • self report