Define schizophrenia
A severe mental illness where people cannot distinguish between what is real and what is not
- an example of psychosis
Which 2 major systems are used for the classification of mental disorders?
2. DSM - 5 (In America)
Outline 2 differences between the ICD-10 and the DSM-5?
Define:
- negative symptom
Positive symptom: A symptom that sufferers have, that normal people do not have
Negative symptom: A symptom that sufferers do not have, that normal people do have
Outline 2 positive symptoms of schizophrenia
Outline 2 negative symptoms of schizophrenia
Evaluate the diagnosis and classification of schizophrenia
Strengths
1. Diagnosis has led to treatments being made available for patients with schizophrenia.
Weaknesses
What 3 ideas make up the biological explanation for schizophrenia?
Outline the findings of a study that suggests schizophrenia has genetic basis
Gottesman (1991)
- found that MZ twins have greatest shared risk of schizophrenia (48%), compared to DZ twins (17%) and siblings (9%)
Is schizophrenia:
Schizophrenia is polygenetic - Each individual gene confers a small increased risk of schizophrenia
2. Schizophrenia is aetiologically heterogenous - Different combinations of genes can lead to schizophrenia
What provides evidence for schizophrenia being polygenetic and aeterologically heterogenous?
The existence of different candidate genes and Ripke et al’s study (Ripke et al studied 37,000 patients and found 108 separate genetic variations associated with increased risk; many coded for dopamine neurotransmitter)
What is dopamine?
Dopamine is a neurotransmitter that generally has an excitatory effect and is associated with the feeling of pleasure.
In what ways can dopamine be linked to schizophrenia?
What are neural correlates?
Patterns of structure/activity in brain that occur in conjunction with an experience (positive and negative symptoms) and may be implicated in the origins of that experience
Outline a neural correlate for avolition (example)
The ventral striatum
Ventral striatum is involved in motivation. Loss of motivation in schizophrenics may be explained by low activity levels here.
- Juck et al found a negative correlation between ventral striatum activity and overall negative symptoms
Outline a neural correlate for hallucinations (example)
The superior temporal gyrus
Allen et al found that patients experiencing auditory hallucinations recorded lower activation levels in the superior temporal gyrus and anterior cingulate gyrus
Evaluate the biological explanation for schizophrenia.
Strengths
Limitations
Name 2 psychological explanations for schizophrenia
2. Cognitive explanations
Outline the 3 main ideas that make up the ‘family dysfunction’ explanation.
How can schizophrenogenic mothers cause schizophrenia?
studies found that schizophrenics had similar types of mothers known as ‘schizophrenogenic mothers’ (mothers who cause schizophrenia). They were ‘cold, rejecting, controlling, and create family of tension/ secrecy. This leads to distrust, paranoid delusions (schizophrenia).
How can the double-bind theory cause schizophrenia?
Children may feel trapped in situations where they fear doing the wrong thing, and receive conflicting messages about what counts as wrong. They cant express feelings about unfairness of situation
- When they ‘get it wrong’ (often), child is punished by withdrawal of love, and as a result, they start to see world as dangerous (disorganised thinking and delusions)
How can expressed emotion cause schizophrenia?
Expressed emotion: the level of emotion expressed towards schizophrenic patient and includes:
High levels of EE can lead to stress in a patient, a primary explanation for relapse in patients with schizophrenia.
Outline the main idea that makes up the cognitive explanation for schizophrenia
Dysfunctional thought processing: lower levels of info processing in some areas of the brain suggest cognition is impaired e.g. ventral striatum linked to negative symptoms
- includes idea of metarepresentation and dysfunction of central control
What is metarepresentation?
Metarepresentation: The cognitive ability to reflect our own thoughts and behaviour.
- Disrupts ability to recognise thoughts as our own - could lead to sensation of hearing voices and having thoughts placed in mind by others (hallucinations).