Schizophrenia-paper 3 Flashcards
Describe what is schizophrenia.
A mental disorder which affects perception, thinking, behaviour and emotion.
- Umbrella term ‘ psychosis’ meaning when someone looses touch with reality.
- Linked with lower socio-economical status and living in urban environments.
Schizophrenia is a syndrome. What does this mean?
There is no single defining characteristic.
How is schizophrenia diagnosed?
Schizophrenia is diagnosed based on the presence of a group of symptoms and signs that occur together.
What is the difference between a positive and negative symptom of schizophrenia?
A positive symptom of schizophrenia is experiences and behaviours in addition to normal functioning. Whereas negative symptoms are the loss or diminution of normal functioning.
What are delusions?
Firm beliefs that are held despite being illogical, or for which there is no evidence.
What are hallucinations?
Disturbance in perception. These are false perceptions hat have no basis in reality.
What is speech poverty?
The inability to speak properly, characterised by the inability to produce fluent words.
What is avolition?
The reduction, difficulty or inability to start and continue with goal directed behaviour.
What is speech disorganisation?
Speech that connects loosely connected thoughts.
What are the 2 ways reliability is assessed when diagnosing?
Inter-rater reliability: The extent two independent clinicians give the same diagnosis.
Test-retest reliability: The extent in which the same person receives the same diagnosis across a time interval.
Describe the different types of validity when diagnosing schizophrenia.
- Criterion validity: The extent to which different assessments lead to the same diagnosis for the same patient.
- Descriptive validity: Patients with schizophrenia should display different symptoms from patients with other disorders.
- Predictive validity: The extent to which a diagnosis predicts what happens to a patient in the future.
What is co-morbidity?
The occurrence of 2 or more conditions in the same person, this is common in schizophrenia.
Buckley et al (2009): 50% of people with Sz also had depression, 47% has substance abuse and 23% had a diagnosis for OCD.
Outline the issue of co-morbidity in relation to reliability and validity in diagnosis and classification of schizophrenia.
(4 marks)
Co-morbidity refers to the occurrence of 2 or more mental disorders in the same person. Buckley et al suggests that co-morbid depression occurs in 50% of people with schizophrenia and 47% have a diagnosis of co-morbid substance abuse.
If two disorders co-occur to such an extent it raises questions about whether they should be considered separate disorders or whether they are part of the same condition. If so, this challenges the validity of the classification and diagnosis of ‘schizophrenia’.
outline the issue of symptom overlap in relation to reliability and validity in diagnosis and classification of schizophrenia.
(4 marks)
The issue of ‘symptom overlap’ means there is an overlap of symptoms between different disorders. For example bi-polar disorder and schizophrenia both involve positive symptoms of delusions and negative symptoms such as the inability to experience joy (anhedonia).
The extent of the overlap and absence of a clear boundary between the disorders suggests that they may not be distinct but are in fat variations of a single condition. This suggests that both classification and diagnosis of these disorders may not be valid.
What is symptom-based approach as an alternative to diagnosis?
- Focuses on a specific problem without the assumption it belongs to a broader cluster of symptoms.
- Attempts to understand the mechanisms responsible for the specific problem.
What is formulation as an alternative to diagnosis?
A summary developed jointly by the person and their clinician. It summarises their difficulties and uses psychological theory to explain why they may be happening.
What does Gottesman’s (1991) research suggest about the degree of genetic relatedness to a person with schizophrenia and risk of developing the disorder?
As genetic relatedness to a person with schizophrenia increases, so does the risk of developing the disorder.
What are candidate genes?
A gene that is believed to be related to a particular trait.
What does polygenic mean?
The inheritance of a trait governed by more than one genes.
What does aetiologically heterogeneous mean?
A number of different combinations of genes can lead to the illness.
What are the findings of Ripke et al’s (2014) research?
The study was done at a molecular level and found that particular genetic variations increased the risk of schizophrenia.
Explain the process of synaptic transmission.
- When an action potential reaches the terminal button of the pre-synaptic neruon it triggers the release of neurotransmitters that are contained in the vesicles.
- The neurotransmitter diffuses across the synapse and then binds with the receptor sites on the post-synaptic neuron.
- Neurotransmitters have either an excitatory or inhibitory effect. Their influences on the post-synaptic neuron are summed up. If the net effect is excitatory, the post-synaptic neuron is more likely to fire whereas if the net is inhibitory it will be less likely to fire- no action potential will be triggered.
What are neural correlates?
Patterns of structure or activity/ function in the brain that occur along with an experience (e.e symptoms of Sz). These may be implicated in the origins of that experience.
What is the diathesis- stress model?
The theory that schizophrenia develops by genetic markers that increase vulnerability to schizophrenia, and external stressors that trigger it to develop.
What are typical antipsychotics?
Older antipsychotics that were developed to reduce dopamine levels in the brain.
What is the DSM-V?
The Diagnostic and Statistical Manual, this is a system to diagnose schizophrenia. This requires at least 1 month of persistent symptoms and has a more specific diagnosis criteria and so requires at least 2 or more of: delusions, hallucinations, disorganised speech and catatonic behaviour.
What is the ICD-10?
The International Classification of Disease, this is a system to diagnose schizophrenia. This requires at least a month of persistent symptoms, this takes a broader approach to diagnosis simply stating that ‘the clinical picture is dominated by relatively stable, often paranoid delusions, usually accompanied by hallucinations’.
Describe the original dopamine hypothesis to schizophrenia.
- Suggests that hyperdopaminergia (abnormally high dopamine levels) in the subcortex is responsible for schizophrenia. For example, hyperdopaminergia in the frontal lobe and specifically Broca’s area, which may be responsible for positive symptoms, such as auditory hallucinations due to overactivity of neurotransmission in auditory areas of the brain.
What is the updated dopamine hypothesis of schizophrenia?
Kenneth Davis et al (1991) proposed the addition of cortical hypodopminergia (abnormally low levels of dopamine in the brains cortex), which would explain symptoms of schizophrenia. For example, low dopamine in the prefrontal cortex (responsible for thinking) could explain cognitive problems such as negative symptoms.
It has also been suggested that cortical hypodopminergia leads to subcortical hyperdopaminergia.
What are the findings of Howes et al’s research?
This research was to try explain the origins of abnormal dopamine function. It seems that both genetic variation and early experiences of stress make some people moree sensitive to cortical hypodopaminergia leading to subcortical hyperdopaminergia.
Why is Glutamate a limitation of the dopamine hypothesis?
One limitation of the dopamine hypothesis is evidence for a central role of glutamate.
Post mortem and live scanning studies have consistently found raised levels of glutamate in several brain regions of people with schizophrenia (McCutcheon et al 2020). In addition, several candidate genes for schizophrenia are believed to be involved in glutamate production or processing.
Why is environmental factors a limitation of genetic explanations of schizophrenia?
There is clear evidence to show that environmental factors increase the risk of developing schizophrenia.
These include biological and physiological influence. Biological risk factors include birth complications (Morgan et al 2017) and smoking THC- rich cannabis in teenage years (Di Forti et al). Psychological factors include childhood trauma which leaves people more vulnerable to adult mental health problems.
Describe how evidence of dopamine is a strength for dopamine playing a role in schizophrenia.
- Amphetamines increase dopamine and worsen symptoms symptoms in people with schizophrenia and induce symptoms in people without (Curran et al 2004).
- Antipsychotic drugs reduce dopamine activity and reduce the intensity of symptoms (Tauscher et al 2014).
- Some candidate genes act on production of dopamine or dopamine receptors.
How is Catherine Ten et al’s research a strength of the dopamine hypothesis?
Rats were induced with schizophrenia like symptoms using amphetamines and then relieved symptoms by using drugs that educe dopamine action.
How does the diagnosis of schizophrenia have good reliability?
A psychiatric diagnosis is said to be reliable when it has high inter-rater reliability and high test-retest reliability. Prior to DSM-5, reliability for schizophrenia diagnosis was low but this has now improved. Flavia Osorio et al reported excellent reliability for diagnosis in 180 participants using DSM-5.
Why is the diagnosis of schizophrenia considered to have low validity?
Elie Cheniaux et al has 2 psychiatrists use criterion validity to independently assess the same 100 clients using ICD-10 and DSM-IV criteria and found that 68 were diagnosed with schizophrenia under the ICD system and 39 under DSM.
Why is gender bias a limitation of diagnosing schizophrenia?
Since the 1980’s men have been diagnosed with schizophrenia more commonly than women. One explanation could be that women are less vulnerable possibly because of genetic factors. However, it is also thought that women are underdiagnosed because they have closer relationships and therefore more support, leading to them often functioning better than men.
Why is culture bias a limitation of diagnosing schizophrenia.
Some symptoms of schizophrenia, such as hearing voices, have different meanings in different cultures. British people of African- Caribbean origin are nine times as likely to receive a diagnosis as British people, although people living in African Caribbean countries are not, ruling out genetic vulnerability.
What role does mutations play in the development of schizophrenia?
Mutations in parental DNA caused by radiation, poison or a viral infection.
The evidence for mutations comes from positive correlations between paternal age (which is associated with increased risk in sperm mutations) and risk of schizophrenia, increasing from around 0.7% with fathers under 25 to 2% with fathers over 50 (Brown et al).
Explain how research support is a strength for the genetic explanation of schizophrenia.
Family studies such as Gottesman show that risk increases with genetic similarity to a family member with schizophrenia.
Adoption studies such as Pekka Tienari et al show that biological children of someone with schizophrenia are at heightened risk even if raised by an adoptive family.
A twin study by Hilker et al showed a concordance rate of 33% between identical twins and 7% for non-identical twins.
Explain how environmental factors is a limitation of the genetic explanation of schizophrenia.
These environmental factors include biological and psychological influences. Biological risk factors include birth complications and smoking THC- rich cannabis in teenage years. Psychological risk factors would include childhood trauma which leaves people more vulnerable to adult mental health problems in general. One study by Nina Morkved et al showed that 67% of people with schizophrenia and related psychotic disorders reported at least one childhood trauma as opposed to 38% of a matched group with non-psychotic mental health issues.
Describe the Schizophrenogenic Mother as an explanation for schizophrenia.
Proposed by Fromm-Reichmann, this is a psychodynamic explanation based on case studies of patients.
The schizophrenogenic mother is cold, rejecting and controlling and tends to cause family climate through tension and secrecy.
This leads to distrust which later leads to paranoid delusions and finally schizophrenia.
Describe the Double Bind Theory as an explanation of schizophrenia.
Proposed by Bateson et al.
Bateson agreed that family climate is important in the development of schizophrenia but emphasises the role of communication style within the family. The family climate in this situation is based on contradictory communication style, where the child is trapped in a ‘no win’ situation and fear getting it wrong.
This makes the individual feel the world is a confusing and dangerous place which leads to paranoid delusions and disorganised thinking.
Bateson was clear this is not the main communication style within the family and this is not a main cause just a risk factor.
Describe high expressed emotion as an explanation of schizophrenia.
This is characterised by high levels of emotions, usually negative emotions, expressed towards a person with schizophrenia by family/carers.
This has several elements:
- verbal criticism and occasionally violence.
- Hostility, including rejection and anger.
- Emotional overinvolvement in the persons life.
These high levels of emotion case serious stress which is the primary explanation for relapse but it has been suggested, through the diathesis stress model, this stress could also contribute to the development of the schizophrenia.
What were the findings of Vaughn and Leff’s research?
High expressed emotion is linked to greater relapse rates than low expressed emotion.
Relapse rates:
Low EE- 12% on drugs, 15% not on drugs.
High EE- >35hrs with family 15% on drugs, 42% not on drugs
<35hrs with family- 53% on drugs, 92% not on drugs.
Describe what is meant by cognitive explanations for schizophrenia.
The main focus is on the role of mental processes such as thinking, language and attention in the development and maintenance of schizophrenia.
Symptoms link to types of dysfunctional thought processing, meaning information processing that does not represent reality accurately and produces undesirable consequences.
Explain how cognitive explanations of schizophrenia link to biology.
Reduced thought processing in the ventral striatum is associated with negative symptoms such as avolition.
Reduced thought processing in the temporal and cingulate gyrus is associated with positive symptoms such as hallucinations.
This lower than usual level of informational processing suggests that cognition is likely to be impaired.
Describe metarepresentation dysfunction as an explanation for schizophrenia.
Frith et al identified metarepresentation as the cognitive ability to reflect on thoughts and behaviour, allowing insite into our own intention and goals as well as being able to read others actions. Dysfunction would disrupt our ability to recognise out own actions and thoughts as being carried out by ourselves rather than someone else. This would explain hallucinations, hearing voices and delusions such as thought insertion.
Describe central control dysfunction as an explanation for schizophrenia.
Frith et al identified issues with the cognitive ability to supress automatic responses when performing deliberate actions. Speech poverty and though disorder could r4esult from the inability to supress automatic thoughts and speech triggered by other thoughts.
Describe how CBT could help someone with schizophrenia symptoms.
(4 marks) (usually with scenario)
ADD APPLICATION TO ALL
- identify irrational beliefs
- help the understand they are not real, explain how it could be their own thoughts
- help see the link between their behaviour, their emotions and their actions.
- offer them alternative interpretations
- give strategies to counter irrational thoughts.
