What is aggression?
Behavior that is intended to cause pain or harm (whether physical or emotional) to others, either individually or in groups
What is predatory aggression?
Aggression between a natural predator and a prey
* Consummatory behavior (access to food)
What is intermale aggression?
Aggression seen between males of the same species. Usually develops to maintain and or challenge dominance relationships between males
* Reproductive behavior (access to mating)
* Consummatory behavior
What does testosterone do to aggression?
Increases aggression, becomes particularly evident with sexual maturity
How does the removal of testes in rats and mice’s affect aggression?
decrease aggressive behavior
Testosterone effects on aggression in humans
- Increased testosterone at puberty does not increase aggression
- Administering testosterone to subjects does not increase aggression
What have other studies found about testosterone and it’s effect on aggression?
- Nonaggressive behavior is correlated with low serum testosterone
- Aggressive behavior in women is correlated with elevated testosterone
What are two confounding variables that can affect testosterone levels?
- Experience—outcome of aggressive encounter
- Dominance—social status
What are the changes in levels of neurotransmitter associated with aggression?
- Dopamine
- GABA
- Vasopressin
- Serotonin
What does the release of serotonin do to aggression?
Inhibits(holds back) aggression * (crayfish, mice, and insects)
* The most aggressive monkeys show the lowest serotonin levels
* Low Serotonin–High Aggression
* High Serotonin–Low Aggression
The ventromedial hypothalamus (VMH) is involved in aggressive behavior (‘attack system’)
What does the Medial amygdala do male rats and mice’s?
Allows male rats and mice to distinguish between male rivals to be attacked and females to be courted.
What is maternal aggression?
aggression in mothers defending their nest or offspring
What is maternal aggression controlled by?
circuits in the VMH, as well as the preoptic area and the premammillary nucleus
What traits do psychopaths display that relate to anti-social behaviors?
- High Intelligence
- Poor self control
- Superficially charming individuals
- Little to no feelings of remorse
- Blunted fear conditioning
- Commit violent acts
