Neuropsychology Causing Aggression Flashcards
How has the amygdala been linked to aggression?
Not working properly = person may be fearless in dangerous situations and engage in agg behaviour without fear of consequence.
How is the corpus callosum linked to aggression?
Not working properly = long-term consequences not thought about properly so reckless agg more likely.
How is the pre-frontal cortex linked to aggression?
It’s used for self-control, so if underactive there will be no “brake” on agg.
How does Raine et al. (1997) support underactive brain function leading to aggression?
Amygdala, corpus callosum and pre-frontal cortex functioned strangely in murders (pleading NGRI).
How do animal studys support the amygdala being linked to aggression?
Animal studies show that if amygdala is stimulated with electricity, the animal displays agg behaviour.
What studies support changes in neurotransmitters increasing aggression?
Dee Higley et al. (1995) studied rhesus monkeys in the wild and found that those who were killed or injured in reckless leaping or fights with older, larger monkeys had lower serotonin levels (serotonin inhibits serotonin)
Which study supports testosterone being linked to aggression?
James Dabbs et al. (1987 + 1995) studied prisoners and found testosterone levels were higher in those who’d been convicted of a violent crime, and had be rated “tough” by other prisoners.
What are Recreational drugs?
Drugs taken for pleasure rather than for medical reasons. They have an effect of the CNS, which is why they are sometimes called ‘psychoactive’ drugs.
What does alcohol do?
Blocks serotonin receptors which lifts mood.
How has alcohol been linked to aggression?
Stephanie Gorka et al. (2013) used MRI scans to study activity between prefrontal cortex and amygdala.
- P’s who had alcohol showed less brain activity than control group.
- Suggests alcohol intereferes with brain’s ability to pass information between emotion centre and decision-making centre.
What is nicotine?
Legal drug which affects dopamine receptors in the “reward pathway”.
How does nicotine work?
Binds to dopamine receptors, which excites the neuron, causing an electrical charge to go down the axon to create real dopamine at the next synapse.
What is the Hypofunctioning reward system?
Neurons in reward pathway change, developing fewer dopamine receptors.
- Brain realises too many dopamine receptors are being stimulated so sharts shutting them down.
- Reduces ability to feel rewarded by the drug but also by normal stimuli, like food or sex.
- Brain needs to produce more dopamine to maintain normal mood states which is why nicotine is addictive: your brain comes to depend on it to maintain its dopamine levels (happens with nicotine).
- Reduces ability to feel rewarded by the drug but also by normal stimuli, like food or sex.
What are amphetamines?
Illegal drugs that involve dopamine in the synapses, e.g. cocaine.
How do amphetamines work?
- Prevents the reuptake of dopamine.
- This means dopamine stays in the synapse, over-stimulating the dopamine receptors and producing feelings of euphoria.
- Long-term effects of desensitisation.
- Number of dopamine receptors goes down, creating addiction, as brain needs more cocaine to make the reward pathway to work.
- Long-term effects of desensitisation.
- This means dopamine stays in the synapse, over-stimulating the dopamine receptors and producing feelings of euphoria.
