Background

Question 1

What is the biochemical explanation of mental illness??

Answer 1

Electrical impulses travel around the brain.
Neurotransmitters pass across the synapse.
Symptoms of mental illness are due to abnormal neurotransmitter levels or action.

Question 2

What is meant by the monoamine hypothesis?

Answer 2

A group of neurotransmitters that regulate mood.

Question 3

Name three examples of monoamines

Answer 3

Serotonin
Noradrenaline
Dopamine

Question 4

How do monoamines (in terms of low levels of serotonin) effect symptoms of depression?

Answer 4

Low levels of serotonin can cause levels of noradrenaline and dopamine to drop.
Low levels of noradrenaline linked to lack of pleasure.
Low levels of dopamine linked to anxiety.

Question 5

What is the role of the gene 5-HTT?

Answer 5

Regulating serotonin levels
People with variations of 5-HTT gene that are under-active more likely to suffer depression after stressful life events.

Question 6

What is the role of MAO-A?

Answer 6

Removes monoamines from the synapse.
If too much MAO-A removes monoamines leading to symptoms of depression.

Question 7

Supporting evidence for the monoamine hypothesis

Answer 7

Meyer (2006)
17 participants with depression who hadn’t taken anti-depressants for 5 months.
17 ‘normal’ who were control group.
PET scans carried out.
Scans showed depressed patients had significantly higher MAOA levels in all brain areas tested.

Question 8

What is meant by the genetic explanation of mental illness?

Answer 8

Characteristics are inherited from parents who pass on genes to us.

Question 9

How are genetic principles investigated?

Answer 9

Concordance rates
Family studies
Twin studies
Adoption studies

Question 10

Evidence for the role of genetics in relation to mental illness

Answer 10

Wender et al. (1986)- biological relatives of a depressed adoptee were x8 more likely than adoptive relatives to have depression.

Question 11

What is the role of the serotonin transporter gene?

Answer 11

Gene responsible for producing serotonin which has been implicated in depression.
Short form of gene leads to inefficient serotonin production.

Question 12

Supporting evidence of the serotonin transporter gene.

Answer 12

Ogilvie et al (1996)- Compared serotonin transported gene in39 people with major depression and 139 from general population.
Significantly higher occurrence of short alleles in depressed groups.

Question 13

How are brain differences investigated?

Answer 13

PET scans- injected with glucose which emits positrons that can be detected by scanner.
MRI

Question 14

What are the four brain areas implicated in depression?

Answer 14

Prefrontal cortex
Limbic system
Amygdala
Hippocampus

Question 15

Evidence for the role of the brain in depression- Hippocampus

Answer 15

Repeated stress may cause neurones in hippocampus to shrink.
Depression may cause hippocampus to shrink/weaken.
Thompson et al (2015)- Study compared brain volume in people with or without depression.
- Depressed people had smaller hippocampus
- Brain differences became more severe the longer an individual suffers from depression.

Question 16

Evidence for the role of the brain in depression- Prefrontal cortex

Answer 16

Shrink with depression.
Frodl- Researched brains of people with depression and compared them to people without depression.
-Abnormalities in hippocampus and prefrontal cortex
- Followed the depressed and non-depressed for three years, found continued decrease in these brain areas of people with depression.

Question 17

Evidence for the role of the brain in depression- Amygdala

Answer 17

Changes in activity in amygdala associated with symptoms of depression.
E.g. increase in activity found when depressed patients are presented with negative stimuli.
Sheline et al (2001)- fMRI scan on 11 depressed patients and 11 normal.
- Scans showed amygdala was more active in depressed patients when both resting and exposed to stimuli.