Aggression booklet 1: Neural and Hormonal mechanisms Flashcards
Which neural mechanism is a central part of the brain involved in processing emotional responses?
The limbic system
What is the amygdala a part of?
The limbic system
Research shows that when the amygdala is stimulated…
It creates an aggressive response
What could happen if there is an abnormality to do with the amygdala?
The levels of testosterone can be raised, making aggressive behaviour more likely
What is the job of the prefrontal cortex?
To mediate the limbic system
What would happen if the PFC was damaged?
The PFC can’t inhibit the limbic system / amygdala leading to an increase in aggression
What did the study Summer (2007) find?
A 14 year old girl had sever anger issues and was found to have a tumour in the limbic system. After the tumour was treated she returned to normal levels of aggression.
What was found in the Kluver and Bucy study?
After removing part of the temporal lobes of rhesus monkeys (destroying the amygdala) their behaviour changed (Kluver-Bucy syndrome) showing a loss of fear and lower aggression levels.
Which neural mechanism is a neurotransmitter?
Serotonin
What effect does serotonin have on the brain?
An inhibitory effect
What does research suggest low levels of serotonin causes?
higher levels of aggression, though other researchers found higher levels of serotonin also cause aggression
How does low levels of serotonin affect the Pre Frontal Cortex?
Serotonin is used as communication between the PFC and amygdala. So the PFC struggles to inhibit the amygdala
What was found in study - Cherek (1996)?
When men take drugs increasing serotonin, their aggression lowered
What are the evaluations of neural mechanisms in aggression?
😍Evidence to support (Delgado)
😍Evidence to support (Lenard)
😞deterministic
😞Reductionist
What was found in supporting study - Delgado?
When stimulating the hypothalamus with electric currents, monkeys became more aggressive.
What was found in supporting study Lenard (2008)?
49 monkeys living on an island were tested and those with lowest levels of serotonin were more likely to be injured or die young. Higher levels of serotonin were more affectionate and groomed more
What hormonal mechanism is involved in aggression?
Testosterone
What is testosterone?
The male sex hormone though to influence aggression from young adulthood onwards due to its actions on brain areas involved in controlling aggression
What does research suggest higher levels of testosterone cause?
-Higher levels of testosterone lead to increased aggression
-Can be supported by how men are more aggressive than women, as they have 10x more testosterone and get less aggressive and they grow older and lose testosterone
How could testosterone be linked to serotonin?
Testosterone acts on serotonin synapses to reduce serotonin transmission, linking the neural and hormonal explanations together
What is the main research study into testosterone as a hormonal mechanism in aggression?
Dolan
What was found in the study of Dolan?
-Found a positive correlation between testosterone levels and aggressive behaviours in a sample of 60 male offenders in UK maximum security hospitals
-This showed hormonal mechanisms influence aggression as it shows when testosterone levels increase, so does aggressive behaviour (correlation though)
What are the evaluations of hormonal mechanisms in aggression?
😂Evidence to support (Dabbs)
😂Evidence from animal studies to support (Beeman)
😢Research could be deemed deterministic
😢Could be seen as reductionist
What must be remembered about evaluations in neural/hormonal mechanisms in aggression?
Both the last 2 points of reductionism and determinism can be recycled for either neural or hormonal, and if you’re asked a mixed question then just use both and any research to evidence from your choice
What is the nueural explanation, the hormonal explanation and the genetic explanation? (to prevent confusion)
Neural = serotonin and limbic system
Hormonal = testosterone
Genetic = Twin studies and MAOA gene
What was found in the study for evidence to support hormonal - Dabbs?
-Measured testosterone levels from saliva of 692 male prisoners
-Found higher testosterone levels in violent offenders (rapists, murderers)
-Lower levels in non-violent offenders (thieves, burglars)
What was found in study for evidence to support hormonal - Beeman?
-Castrated male mice and found that aggressiveness reduced
-Later injected mice with testosterone which re-established aggressiveness