Schizophrenia

Question 1

Schizophrenia definition

Answer 1

A severe mental illness where contact with reality and insight are impaired. Suffered by about 1% of the population

Question 2

What are hallucinations? (Positive symptom)

Answer 2

• Unusual sensory experiences
• Can be experienced in relation to any sense
• E.g hearing voices, seeing distorted facial expressions or people that aren’t there

Question 3

What are delusions? (Positive symptom)

Answer 3

• Irrational beliefs
• Paranoid delusions= the sufferer may believe they are being persecuted
• Delusions of grandeur= believes they are famous or very important

Question 4

What is avolition? (negative symptom)

Answer 4

-Loss of motivation to carry out tasks and results in lowered activity levels

Question 5

What is speech poverty? (negative symptom)

Answer 5

-Reduced frequency and quality of speech

Question 6

Define classification

Answer 6

The process by which the mental illness are separated into types

Question 7

Define diagnosis

Answer 7

The process by which a clinician assesses an individual and decides which type of illness they are suffering from

Question 8

Name the 2 major systems for the classification of mental disorders

Answer 8

The DSM-5

The ICD-10

Question 9

The DSM-5

Answer 9

• Mostly used in the US
• Version 5 is the most recent
• For a person to be diagnosed as having schizophrenia, the DSM sets that they must have at least 2 of: delusions, hallucinations, disorganised speech, catatonic behaviour, negative symptoms
• Symptoms have to be present for at least 6 months

Question 10

The ICD-10

Answer 10

• The World Health Organisation’s International system

- Recognises a range of subtypes. E,g paranoid schizophrenia

Question 11

What is reliability?

Answer 11

• Consistency of diagnosis
• The classification system should provide the same outcomes each time
• Clinicians should reach the same conclusions at 2 different points in time )test re test reliability)

Question 12

Copeland (1971)

Answer 12

• Gave 134 US and 194 British psychiatrists a description of a patient
• 69% of US psychiatrists diagnosed SZ
• Only 2% of British gave the same diagnosis

Question 13

What is validity?

Answer 13

• The accuracy of diagnosis
• Trustworthy
• Whether a diagnosis can be validated by someone improved after being given treatment to help with that diagnosis

Question 14

Rosenhan (1973)

Answer 14

• Aim to investigate te reliability of diagnosis by testing whether a sane person reporting 1 symptom of schizophrenia would be given a diagnosis
• 8 healthy people went to psychiatric hospitals claiming to hear voices (thud)
• When admitted to hospital, the symptoms went
• 7 were diagnosed with SZ
• On average it took 19 days for release
• Whilst on the ward, normal behaviour was often interpreted as abnormal
• Concluded that diagnosis is unreliable

Question 15

What is co morbidity?

Answer 15

• Where one or more disorders or diseases occur simultaneously with SZ and can create problems with reliability of diagnosis as there may be confusion over which actual disorder is being diagnoised
• E.g people with SZ often also suffer from depression

Question 16

What is symptom overlap?

Answer 16

• There is considerable overlap of symptoms of SZ and other conditions
• E.g both SZ and bipolar involve negative symptoms like avolition

Question 17

What is gender bias?

Answer 17

• The tendency for diagnosis criteria to applied different to males and females
• It has been suggested the male sufferers are more likely to suffer from more negative symptoms

Question 18

What is cultural bias?

Answer 18

The tendency to over diagnose members of other cultures as suffering from SZ

Question 19

What are the key features of the biological explanation of SZ?

Answer 19

• Genetics
• Dopamine Hypothesis
• Neural correlates

Question 20

Biological explanation- genetics

Answer 20

• SZ tends to run in families
• Polygenic- different combinations of genes makes individuals more vulnerable
• Having these genes doesn’t necessarily mean all individuals will develop SZ

Question 21

Biological explanation- The Dopamine hypothesis

Answer 21

• Suggests that an excess of the neurotransmitter dopamine in certain regions of the brain is associated with positive and negative symptoms of SZ
• Messages from herons that transmit dopamine fire too easily/often
• Hyperdopaminergia= high levels of dopamine activity in the sub cortex is believed to cause speech poverty

Question 22

Neural correlates of negative symptoms

Answer 22

• Activity in the ventral strialum has been linked to the development of evolution
• The ventral striatum are believes to be particularly involved in the anticipation of reward for certain actions
• Therefore, if there is abnormality in areas such as the ventral striatum, there would be a lack of motivation (avolition)

Question 23

Neural correlates of positive symptoms

Answer 23

-Reduced activity in the superior temporal gyrus and anterior cingulate gyrus have been linked to the development of auditory hallucinations
(correlation not causation!)

Question 24

What are neural correlates?

Answer 24

Patterns of structure or activity in the brain that occur in conjunction with an experience

Question 25

Explain the use of twin studies

Answer 25

- Twin studies provide a natural experimental design - MZ twins have the same genes where as DZ twins are 50% genetically similar - It is presumed that twins share a similar environment. Therefore the influence of genetic factors can be assessed with the IV as the degree of genetic similarity

Question 26

What is concordance rate?

Answer 26

A measure of similarity between 2 individuals

Question 27

Twin studies and concordance rate

Answer 27

- MZ twins have 100% concordance rate= behaviour must be purely genetic - MZ twins have a concordance rate less than 100%= behaviour must be partly down to the environment - MZ and DZ twins have similar concordance rates= Behaviour must be down to the environment

Question 28

Joseph (2004)

Answer 28

-Calculated that the pooled data for all SZ twin studies carried out prior to 2001 showed a concordance rate for MZ twins of 40% and 7% for DZ twins. This shows that SZ must be partly genetic

Question 29

Explain the use of family studies

Answer 29

-Family studies find individuals who have SZ and determine whether their biological relatives are similarly affected more often than non biological relatives

Question 30

Gottesman (1991)

Answer 30

- Carried out a large family study - Found that if both parents suffer from SZ, then there is a 46% chance of also developing the disorder - One SZ parent= concordance rate of 13% - Concluded that the greater the degree of genetic relatedness, the greater the risk of developing SZ

Question 31

Explain the use of adoption studies

Answer 31

- These are studies of genetically related individuals who have been reared apart due to being adopted - Allows researchers to overcome the problem of disentangling genetic and environmental influences

Question 32

Strengths of the biological explanation

Answer 32

- Dopamine hypothesis has lead to the development of effective treatment - Considerable evidence

Question 33

Weaknesses of the biological explanation

Answer 33

- Neural correlates should a correlation not causation. For example, negative symptoms may mean less info passes through the ventral striatum resulting in reduced activity - Biological explanations are reductionist- ignores psychological factors. An individual may have a genetic predisposition for SZ but it may be due to environmental factors that leads to the onset of the condition

Question 34

What are antipsychotics?

Answer 34

- Help the person function as well as possible - Clinicians will tend to use a combination of medication and psychological therapies - They work by reducing dopamine transmission in areas of the brain associated the SZ symptoms

Question 35

Typical antipsychotics

Answer 35

- Developed in the 1950s - E.g Clorpromazine - Eliminates positive symptoms such as hallucinations

Question 36

Atypical antipsychotics

Answer 36

- 1970S - E.g Clozapine - Fewer side effects - Proven effective on positive nd negative symptoms - Act on the dopamine system by blocked D2 receptors