Biological Explanations - Neurotransmitter Imbalances

Question 1

What neurotransmitters are linked to aggression?

Answer 1

Dopamine and serotonin

Question 2

What are the levels of dopamine and serotonin which are associated with aggression?

Answer 2

Low levels of serotonin and high levels of dopamine

Question 3

What effect do normal levels of serotonin have?

Answer 3

A calming effect on the brain

Question 4

What effect do low levels of serotonin have?

Answer 4

The inhibitory effect is removed, resulting in less control of impulsive and aggressive responses

Question 5

Which part of the brain is most affected by levels of aggression?

Answer 5

The frontal cortex

Question 6

How does the influence of serotonin on aggressive behaviour explain the relationship of alcohol and aggressive behaviour?

Answer 6

Alcohol consumption causes disturbances in the metabolism of serotonin in the brain, resulting in depleted serotonin levels which may induce aggressive behaviour

Question 7

What studies are linked to neurotransmitter imbalances?

Answer 7

Mann et al

Ferrari et Al

Question 8

What study is linked to serotonin?

Answer 8

Mann et al

Question 9

What were Mann et al’s findings?

Answer 9

All participants were given dexfenfluramine (a drug which depletes serotonin levels in the brain). After completing a questionnaire, they found aggression and hostility levels were increased among males but not females.

Question 10

Evaluation points for Mann et al’s study…

Answer 10

It is less socially desirable to admit aggressive traits, women may have been more susceptible to this
Lack of validity in behaviour as questionnaire results are subjective and doesn’t represent their actions - only what they say. This may lead to a lack of validity and in turn the explanation that low serotonin leads to aggressive behaviour is incorrect.

Question 11

What are the explanations of serotonin and its affects on aggression?

Answer 11

Low serotonin levels cause an increase in levels of aggression
Increases serotonin receptors cause and increase in levels of aggression

Question 12

How are serotonin receptors created?

Answer 12

When serotonin is chronically depleted the brain responds increasing the number of receptors

Question 13

What is an example of dopamine and aggression?

Answer 13

Amphetamines increase dopamine levels in the brain and are often associated with increased aggression

Question 14

What has been successful in reducing aggressive behaviour?

Answer 14

Dopamine antagonists (reduce dopamine activity)

Question 15

What are dopamine antagonists?

Answer 15

Chemicals which reduce dopamine activity thus reducing aggressive behaviour

Question 16

What study supports the influence of serotonin and dopamine in aggressive behaviour?

Answer 16

Ferrari et al

Question 17

What were Ferrari et al’s findings?

Answer 17

On the 11th day, even though the rat did not fight, it was expecting to as a result of the previous ten days of fighting. This is clear as the rats dopamine levels had increased and the serotonin levels decreased. The change in brain chemistry illustrates a link between aggressive behaviour and serotonin and dopamine levels.

Question 18

What does Ferrari et al’s study demonstrate?

Answer 18

It is not necessarily an innate baseline of neurotransmitters that causes aggression but an interaction with experience

Question 19

What debate can be used for neurotransmitters?

Answer 19

Animal debate

Question 20

What is the argument in favour of using animals in research?

Answer 20

We are morally obliged to ease human suffering thus can use animals for research to protect humans from harm. Evolution has places humans at the top of the phylogenetic tree so it is natural to make use of lower animals for our health benefit

Question 21

What is the argument against using animals in research?

Answer 21

There are more modern techniques which can also assess levels of aggression on humans which dint result in harming animals e.g CT, MRI and PT scans

Question 22

What are neurotransmitters?

Answer 22

Chemicals that allow impulses to travel between neurones

Question 23

Who investigated the effects of dopamine on aggression?

Answer 23

Lavine

Mann et al

Question 24

Who investigated the effects of amphetamines and aggression?

Answer 24

Lavine

Question 25

Who studied alcohol and serotonin?

Answer 25

Badawy