Schizophrenia Flashcards
What is schizophrenia?
A severe mental disorder where contact with reality and insight are impaired - causing profound disruption of cognition and emotion.
What is meant by classification of mental disorder?
The process of organizing symptoms into categories based on which symptoms frequently cluster together.
What is the process of diagnosing a disorder?
- We need to distinguish one disorder from the next.
- We identify clusters of symptoms that occur together - which can then be classified as one disorder.
- Diagnosis can then occur, identifying symptoms and deciding what disorder the person has.
What are the two current classification of mental disorder systems?
- The international classification of disease (ICD-10)
- Diagnostic and statistical manual edition 5 (DSM-5)
How does the ICD-11 and DSM-5 differ in classification of schizophrenia?
- In the DSM-5 one or more POSITIVE symptoms are required for diagnosis whereas in the ICD-11, two or more NEGATIVE symptoms are sufficient for diagnosis.
- The DSM-5 requires delusion, hallucination or disorganised speech to be present for diagnosis.
- The DSM-5 requires symptoms to persist over 6 months, whereas the ICD-11 requires symptoms present most of the time for psychotic episodes lasting at least 1 month.
What % of the worlds population have schizophrenia?
1%
Define positive symptoms of schizophrenia
Atypical symptoms experienced IN ADDITION to normal experiences
Define negative symptoms of schizophrenia.
Atypical experiences that involve the loss of usual experiences and abilities.
What are the two positive symptoms of schizophrenia?
- Hallucinations
- Delusions (paranoia)
What are hallucinations (a positive symptom of schizophrenia)
- Unusual sensory experiences that can either have no relation to reality or may be distorted perceptions of things that are there.
Hallucinations can be experienced with any sense, for example: hearing commentary voices that can also converse. In addition, they may see distorted facial expressions or people/animals that are not there.
What are delusions (a positive symptom of schizophrenia)
- Beliefs that have no basis in reality and are irrational - these make sense to the individual but seem bizarre to others.
What are common delusions in schizophrenia?
- Being an important historical, political or religious figure such as Napoleon or Jesus.
- Belief that they are being persecuted by the government or aliens and belief they have superpowers.
- Belief that they are under external control.
What are the two negative symptoms of schizophrenia?
- Avolition
- Speech poverty (alogia)
What is avolition? (a negative symptom of schizophrenia)
- Loss of motivation and lowering of activity.
- They have sharply reduced motivation for goal-directed activity (actions performed to produce a consequence)
What 3 signs of avolition did Andreasen outline?
- Poor hygiene and grooming
- Lack of persistence in work or education
- Lack of energy
What is speech poverty/alogia? (a negative symptom of schizophrenia)
- Change in patterns of speech, being a reduction quality and amount of speech.
- This is accompanied by a delay in verbal responses during conversation
List the ‘issues in diagnosis and classification’ for schizophrenia
- Good reliability
- Low validity
- Co-morbidity
- Gender bias
- Culture bias
- Symptom overlap
Evaluate validity and reliability in diagnosis and classification of schizophrenia
- Good reliability.
One strength of diagnosing schizophrenia is reliability, or consistency. For a psychiatric diagnosis to be deemed reliable, different diagnosing clinicians need to reach the same diagnosis for the same individual (inter-rater reliability). In addition, test-retest reliability also determines diagnostic reliability where the same clinician reaches the same diagnosis for the same individual on two occasions. Prior to the DSM-5, reliability in diagnosing schizophrenia was low but has since improved.
A study reported excellent reliability for the diagnosis of schizophrenia in 180 individuals using the DSM-5. Pairs of interviewers achieved inter-rater reliability of +.97 and test-retest reliability of +.92. This means we can be reasonably sure that diagnosis is consistently applied. - Low validity.
A limitation into the diagnosis and classification of schizophrenia is validity. In general, validity refers to whether we are assessing what we are intending to assess. For diagnosis, criterion validity is used to assess the validity of diagnosis. A study had two psychiatrists independently assess the same 100 clients with one using the DSM-IV and the other using the ICD-10. For the ICD-10, 68/100 were diagnosed with schizophrenia compared with only 39/100 being diagnosed under the DSM-5 criteria. This suggests schizophrenia is either over or under diagnosed according to the diagnostic system - suggesting low criterion validity. - COUNTERPOINT TO VALIDITY.
Despite a disconcordance in diagnosis between two classification systems, it was reported that there was excellent agreement between clinicians when they used measures to diagnose schizophrenia from the DSM-5. This means that criterion validity for diagnosing schizophrenia is actually good provided it takes place under a singular diagnostic system.
Evaluate co-morbidity and symptom overlap in issues with the diagnosis and classification of schizophrenia
- Co-morbidity
Another limitation of schizophrenia diagnosis is co-morbidity with other conditions. Co-morbidity, as a definition is where conditions can occur together. If conditions occur together frequently, it questions the validity of diagnosis and classification due to giving the impression that it could be a single condition as opposed to two. Schizophrenia, for example, is commonly diagnosed alongside other conditions. For example, 1/2 of those with schizophrenia are diagnosed with depression or substance abuse. This poses a problem for classification as it means schizophrenia may not exist as a distinct condition. As a result, diagnosis is a problem as some diagnosed with schizophrenia may display unusual cases of conditions such as depression. - Symptom overlap.
A further limitation in diagnosing schizophrenia is symptom overlap. In schizophrenia’s case, symptom overlap is where there is considerable overlap between symptoms of schizophrenia and symptoms seen in other conditions. Using an example, both schizophrenia and bipolar disorder involve similar symptoms such as delusions and avolition - also having similar characteristics like having cyclic patterns of symptoms. In terms of classification, this suggests schizophrenia and bipolar disorder may not be two different conditions but variations of a single condition. For diagnosis, it means schizophrenia is hard to distinguish from bipolar disorder resulting in a false diagnosis. As with co-morbidity, symptom overlap means that schizophrenia may not exist as a single condition and even if it is, it is harder to diagnose as classification and diagnosis are flawed.
Evaluate gender bias and culture bias in issues with the diagnosis and classification of schizophrenia
- Gender bias
A limitation of diagnosing and classifying schizophrenia is the existence of gender bias. Since the 1980s, men are more commonly diagnosed with schizophrenia, at a figure of 1.4:1 ratio compared to women. This can be explained by the fact women are less vulnerable than men, potentially due to genetic factors. Despite this, it is more likely that women are under diagnosed due to having closer relationships and therefore, more support. This means that women with schizophrenia may be better functioning than men. This under diagnosis is a gender bias and means women may not therefore be receiving treatment and services that benefit them. - Culture bias
Another limitation of schizophrenia diagnosis is culture bias. Some symptoms of schizophrenia, such as hearing voices, have different meanings in different cultures. For example - in Haiti, hearing voices is believed to be communication from ancestors. In the UK, British people of Afro-Carribean origin are 9x more likely to be diagnosed with schizophrenia compared to white British people. This does not correlate with the fact that people living in African or Carribean countries are not, ruling out genetic vulnerability. To explain this, it is likely that culture bias occurs in diagnosis of clients. Psychiatrists of different cultural backgrounds could over interpret symptoms in Black British people due to ethnocentrism. In summary, due to culture bias, British African-Carribean people may receive discrimination due to a culturally-biased diagnosis system.
Define classification
The process of organizing symptoms into categories based on which symptoms frequently cluster together
What is the difference between co-morbidity and symptom overlap?
- Co-morbidity is the occurrence of two or more disorders together.
- Symptom overlap is where two or more conditions share symptoms (bipolar and schizophrenia example)
What are the two biological explanations of schizophrenia?
- Genetics
- Neural correlates
What are the 3 genetic explanations for schizophrenia?
- Family studies
- Candidate genes
- Role of mutation
What psychologist carried out family studies into schizophrenia?
Gottesman
For different family members diagnosed with schizophrenia, what is an individuals chances of developing it? (GOTTESMAN FAMILY STUDY)
- Aunt: 2% chance
- Sibling: 7%
- Identical twin: 48%
What is the role of mutation in schizophrenia (biological explanation)
- Mutation in DNA is believed to be a factor in developing schizophrenia, regardless of family history.
- A study found positive correlations between paternal age (associated with risk of sperm mutation) and risk of schizophrenia.
0.7 risk in fathers under 25, 2% in fathers over 50.
What are candidate genes in schizophrenia?
Candidate genes are genes that create vulnerability for developing schizophrenia.
Who studied candidate genes as a genetic explanation for schizophrenia (biological explanations for schizophrenia)
Ripke et al.
Is schizophrenia polygenic?
- It appears so.
Modern research supports that multiple genes are involved in the development of schizophrenia.
These genes are most likely involved in coding for neurotransmitters.
What did Ripke do and find in his genome-wide study on candidate genes?
- Ripke combined data on the genetic makeup of 37000 people diagnosed with schizophrenia and compared these to a control of 113000 people.
- Ripke found 108 separate genetic variations were associated with an increased risk of schizophrenia.
Why is schizophrenia aetiologically heterogenous?
Different studies identified different candidate genes.
It is aetiologically heterogenous as different combination of factors, including genetic variation can lead to the condition.
What is meant by neural correlates? (a biological explanation for schizophrenia)
- Patterns of structure or activity in the brain that occur simultaneously with an experience, and can be implicated in the origin of this.
What is the best-known neural correlate of schizophrenia?
- Dopamine (DA)
What are explanations under neural correlates?
- The original dopamine hypothesis
- The updated versions of the dopamine hypothesis
Outline the original dopamine hypothesis (biological explanations)
- The original dopamine hypothesis was founded on the discovery that anti-psychotic drugs used to treat schizophrenia caused symptoms similar to Parkinson’s disease, a condition characterized by low DA levels).
- Therefore, the original dopamine hypothesis concluded that schizophrenia may be associated with high levels of dopamine in subcortical levels of the brain.
In short, what is the main claim of the original dopamine hypothesis?
- Schizophrenia may be the result of hyperdopaminergia in subcortical areas of the brain.
How does the original dopamine hypothesis explain symptoms such as speech poverty and auditory hallucinations? (biological explanations for schizophrenia)
- An excess of DA receptors in pathways from the subcortical areas to the Brocas area (responsible for speech production) explain these symptoms.
What psychologist contributed to the UPDATED dopamine hypothesis?
Davis et al.
What does the updated dopamine hypothesis claim?
What did Davis et al propose as part of the updated dopamine hypothesis?
- Cortical hypodopaminergia can be implicated in the symptoms of schizophrenia (abnormally low levels of DA in the cortex)
How does hypodopaminergia as part of the updated dopamine hypothesis explain symptoms of schizophrenia?
Low DA in the prefrontal cortex (responsible for thought) can explain cognitive problems in schizophrenia such as avolition.
In short, what is the main claim of the UPDATED dopamine hypothesis?
- Both Cortical hyperdopaminergia and hypodopaminergia can cause schizophrenic symptoms.
It is about the disparity of dopamine in different sections of the brain (high DA in subcortical, low DA in prefrontal cortex)
Hypodopaminergia can lead to hyperdopaminergia, true or false?
True
Evaluate the genetic basis as a biological explanation for schizophrenia
- Research support
One strength of the genetic explanation as a biological explanation for schizophrenia is the strong evidence base.
Gottesman’s, alongside other family studies demonstrate that risk increases with genetic similarity to a family member with schizophrenia.
Adoption studies are utilised as research support, showing how biological children of parents with schizophrenia are at heightened risk regardless of the environment they were adopted into. A recent twin study showed that there was a concordance rate of 33% for monozygotic twins and 7% for dizygotic twins.
This supports the notion that some people are more vulnerable to schizophrenia as a result of genetic makeup. - Environmental factors.
A limitation for the genetic explanation of schizophrenia is that there is distinct evidence to show environmental factors increase the risk of schizophrenia. Environmental factors consider both biological and psychological influences. Biological risk factors include birth complications and the intake of THC-rich cannabis in teenage years. Psychological risk factors include childhood trauma, leaving people more vulnerable to adult mental health problems - having links to schizophrenia. In one study 67% of people with schizophrenia and related psychotic disorders reported at least one childhood trauma as opposed to 38% of a matched control group.
This evidence suggests that genetic factors alone cannot provide a complete explanation for schizophrenia.