SCHIZOPHRENIA Flashcards
What percentage of the world has schizophrenia
1%
Who are more likely to have it
(3 things)
Men
City dwellers
Lower socio-economic groups
Name the two major systems for the classification of mental disorders
- World Health Organisation’s International Classification of Disease (ICD-10)
- The American Psychiatric Associations Diagnostic and Statistical manual edition 5 (DSM-5)
What is the difference between the DSM and ICD when diagnosing schizophrenia
The DSM requires at least one positive symptom to be present.
Two more negative symptoms are sufficient in ICD.
What have both classification systems stopped doing and why
Diagnosing subtypes of schizophrenia
Someone diagnosed with a subtype of schizophrenia may not show the same symptoms a few years later.
Name the two positive schizophrenia symptoms
Hallucinations
Delusions
Describe hallucinations and environment
Unusual sensory experiences.
Some hallucinations are related to the environment and others have no relationship to what the senses are picking up from the environment.
Describe delusions
Irrational beliefs.
What does the term positive symptoms mean
Atypical symptoms experienced in addition to normal experiences.
These are additional experiences beyond those of ordinary existence.
What do common delusions involve
Being an important historical, political or religious figure.
Persecution - by government or aliens
Having superpowers
What are negative symptoms
Atypical experiences that represent the loss of a usual experience such as a loss of clear thinking or the loss of motivation.
The loss of usual abilities and experiences.
Name the two negative symptoms
Speech poverty
Avolition
What is speech poverty
Changes in patterns of speech.
Reduction in the amount and quality or a delay in the persons verbal response during conversation.
What is speech disorganisation
How is it classed
Speech becomes incoherent or the speaker changes topic mid sentence.
It is a positive symptom.
What is avolition
Finding it difficult to begin or keep up with goal-directed activities.
Who identified the 3 signs of avolition (and year)
Nancy Andreasen (1982)
What are the 3 signs of avolition
Poor hygiene and grooming
Lack of persistence in work or education
Lack of energy
List the positives in diagnosis and classification
Good reliabilty
List the issues in diagnosis and classification
Low validity
Co-morbidity
Gender bias in diagnosis
Culture bias in diagnosis
Symptoms overlap
When is a psychiatric diagnosis deemed reliable?
State the two key words and describe
Inter-rater reliability
When different diagnosing clinicians reach the same diagnosis for the same individual
Test-retest reliability
When the same clinician reaches the same diagnosis for the same individual on two occasions.
How has DSM-5 affected reliability with schizophrenia diagnosis
Improved it
Who reported excellent reliability for the diagnosis of schizophrenia (year)
Flavia Osorio et al. (2019)
How many people did Flavia Osorio test
What were the results
180
Pairs of interviewers achieved inter-rater reliability of +.97 and test-retest reliability of +.92
What is one way to assess validity of a psychiatric diagnosis
Criterion validity
Who assessed criterion validity (year)
Elie Cheniaux (2009)
What did Elie Cheniaux do to test criterion validity?
What are the results?
What do the results mean?
She had two psychiatrists 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.
This suggests that schizophrenia is either over or under diagnosed according to which system is used. This means criterion validity is low.
Who proved high criterion validity (year)
What did they prove? What does this mean?
Flavia Osorio (2019)
Found there was an excellent agreement between clinicians when they used two measures to diagnose schizophrenia both derived from the DSM system.
This means that the criterion validity for diagnosing schizophrenia is actually good provided it takes place within a single diagnostic system.
What is co-morbidity
The occurrence of two disorders or conditions together
Why is co-morbidity bad?
If conditions occur together then the validity of their diagnosis and classification is questioned.
The two conditions may actually be one.
Who proved high co-morbidity
Buckley at al.
What did Buckley et al find about co-morbidity
Half of those diagnosed with schizophrenia also has a diagnosis of depression or substance abuse.
Why is co-morbidity an issue in diganosis
Schizophrenia may not exist as a distinct condition
Some people diagnosed with schizophrenia may just have unusual symptoms of depression.
Are men or woman more commonly diagnosed
Since when
Ratio - who found the ratio (year)
Since the 1980s men have been diagnosed more
1.4:1 - Fischer and Buchanan (2017)
What are two possible explanation for more men being diagnosed then women
What is more likely - who found this and year
Woman are less vulnerable than men because of genetic factors.
More likely women are underdiagnosed as they have closer relationships with better support. Cotton et al (2009)
How is culture bias an issue with diagnosing schizophrenia
Hearing voices has different meanings in different cultures. In Haiti it is seen as communication from ancestors
Case study proving culture bias (name and year)
Pinto and Jones (2008) British people of African-Caribbean origin are up to 9x more likely to receive a diagnosis as white British people, although people living in African-Caribbean countries are not.
Explanation for culture bias
Researcher and year
Culture bias in diagnosis of clients by psychiatrists from a different cultural background.
Leads to an over interpretation of symptoms in black British people
Escobar (2012)
What is symptom overlap
Occurs when two or more conditions share symptoms
Give an example of symptom overlap between schizophrenia and another condition
Schizophrenia and bipolar disorder involved both the positive symptom of delusions and negative symptom of avolition.
What does symptom overlap suggest
That two disorders may not be different but variations of a single condition.
What have family studies proved about the risk of schizophrenia
The risk increases in line with genetic similarity to a relative with the disorder.
Who did the large scale family study on schizophrenia
Irving Gottesman (1991)
If someone has an aunt with schizophrenia what is the chance they have it
How about siblings
How about identical twins
2%
9%
48%
Why else does having a family member with schizophrenia increase your chances besides genetics
What does this mean
They share aspects of their environment
The correlation represents both
How many genes control schizophrenia
It is not a single gene but polygenic
What genes most likely impact schizophrenia
Those coding for neurotransmitters including dopamine
Who combined all the previous data from geome-wide studies of schizophrenia
Stephen Ripke et al (2014)
What did Stephen Ripke do
Compared the genetic makeup of-up of 37,000 people with a diagnosis of schizophrenia to 113,000 controls
What did Stephen Ripke find
That 108 separate genetic variations were associated with slightly increased risk of schizophrenia
Why is schizophrenia aetiologically heterogenous
Because different studies have identified different candidate genes
Different combinations of factors can lead to the condition
Can schizophrenia occur without family history
Yes
What is an explanation for schizophrenia occurring without family history
Mutation in parental DNA caused by radiation, poison or viral infection.
What is the evidence of mutation causing schizophrenia
Who found this
Positive correlation with age of the parent (associated with increased risk of sperm mutation) and risk of schizophrenia
Risk increases from around 0.7% with fathers under 25 to over 2% in fathers over 50
Brown et al (2002)
What are neural correlates
Patterns of structure or activity in the brain that occur in conjunction with an experience and may be implicated in the origins of that experience
What is the best-known neural correlate of schizophrenia
Dopamine
How was the original hypothesis of dopamine and schizophrenia found
Who found it
Based on the discovery that drugs used to treat schizophrenia (antipsychotics which reduce DA) caused symptoms similar to parkinsons disease a disease associated with low DA levels.
Seeman (1987)
What dopamine levels are associated with schizophrenia (keyword)
Where are these levels occuring
High levels - hyperdopaminergia - in subcortical areas of the brain
How can dopamine levels explain speech poverty and auditory hallucinations
High levels of dopamine receptors in pathways from the sub cortex to the Broca’s Area (responsible for speech production)
Who updated the dopamine hypothesis and when
Kenneth Davis et al 1991
What did Kenneth Davis propose
The addition of cortical hypodopaminergia
Abnormally low DA in the brains cortex
How can low levels of dopamine explain cognitive problems
Low levels of DA in the prefrontal cortex which is responsible for thinking - negative symptoms
What can cortical hypodopaminergia lead to
It can lead to subcortical hyperdopaminergia so high and low levels of dopamine in different brain regions
What two factors can make some people more sensitive to cortical hypodopaminergia and subcortical hyperdopaminergia
Who states this
Genetic variations
Early experiences of stress, both psychological and physical
Howes et al (2017)
What is one strength of the the genetic explanation
It has a strong evidence base
Name and explain three studies that show a strong evidence base for genetic
Gottesman
Pekka Teinari et al. (2004)
Rikke Hilker et al. (2018)
What was Pekka Tienari et al. Study
Adoption study shows that biological children of parents with schizophrenia are at heightened risk even if they grow up in an adoptive family.
What was Rikke Hilker et al. (2018) study
A twin study showing a concordance rate of 33% for identical twins and 7% for non-identical.
What is one limitation of the genetic explanation
There is clear evidence to show that environmental factors also increase the risk of developing schizophrenia
What two influences do environemntal factors include
Both biological and physical
Name the biological risk factors and the study’s for them
Birth complications Morgan et al. (2017) and smoking THC rich cannabis in teenage years Di Forti et al. 2015
Name the psychological risk factors and who studied it
Childhood trauma which leaves people more vulnerable to adult mental health problems.
Nina Morkved et al. (2017)
What did Nina Morkved find
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.
What is one strength for the evidence of dopamine
Support for the idea that dopamine is involved in
What do Amphetamines do and who discovered this
They increase DA and worsen symptoms in people with schizophrenia and induce symptoms in people without Curran et al. (2004)
What do antipsychotic drugs do and who discovered this
They reduce DA activity and therefore the intensity of symptoms Tauscher et al. (2014)
What can sometimes act on the production of DA or DA receptors
What does this suggest
Candidate genes
That dopamine is involved in the symptoms of schizophrenia
What is a limitation of the dopamine hypothesis
The evidence for a central role of glutamate.
How did they find the role of glutamate in schizophrenia
What is it
Who studied this
Post-mortem and live scanning have consistently found raised levels of the neurotransmitter in serveral brain regions
McCutcheon et al. (2020)
What is the link between schizophrenia genes and glutamate
Several candidate genes for schizophrenia are believed to be involved in glutamate production or processing.
Name the biological explanations for schizophrenia
The genetic basis
Neural correlates
Name the psychological explanations for schizophrenia
Family dysfunction
Cognitive explanations
What is family dysfunctions
How does it link to schizophrenia
Refers to processes within a family such as poor family communication, cold parenting, and high levels of expressed emotion.
These may be risk factors for both the development and maintenance of schizophrenia
What type of explanation is the schizophrenogenic mother
Psychodynamic
What is the schizophrenogenic mother
A cold, rejecting and controlling mother who tends to create a family climate characterised by tension and secrecy.
Who coined the schizophrenogenic mother
Where did it come from
Frieda Fromm-Reichmann (1948)
It was based on the accounts she heard from her patients about their childhoods.
What does the schizophrenogenic mother lead to in the child
Leads to distrust that later develops into paranoid delusions.
Who came up with the double-blind theory
Gregory Bateson et al. (1972)
What does the double-blind theory emphasise
What did Gregory make clear about his findings
The role of communication style within a family
That it is not the main communication style in the family and not the only factor just a risk factor
Explain the double-blind theory
A child fears of doing wrong.
They receive mixed messages about what doing wrong is
They feel unable to comment on the unfairness of the situation
When they get it wrong they are punished by withdrawal of love
This leaves them thinking the world is confusing and dangerous
What symptoms reflect the double blind theory
Disorganised thinking and paranoid delusions
What theory’s fall under family dysfunction
The schizophrenogenic mother
The double-blind theory
Expressed emotion
What is Expressed emotion (EE)
The level of emotion, in particular negative emotion, expressed towards a person with schizophrenia by their carers who are often family members.
What are the 3 elements of EE
- Verbal criticism of the person, occasionally accompanied by violence
- Hostility towards the person, including anger and rejection
- Emotional overinvolvement in the life of the person, including needless self-sacrifice
What do these high levels of expressed emotion cause
Stress
What 2 impacts can EE have on a person
Cause a relapse in people with schizophrenia
Can trigger an onset of schizophrenia
What are the 3 cognitive explanations
Dysfunctional thinking
Metarepresentation dysfunction
Central Control dysfunction
What is cognitive explanations
Explanations that focus on mental processes such as thinking, attention and language
What is dysfunctional thought processing
Information processing that does not represent reality accurately and produces undesirable consequences
Reduced thought processing in the ___ is associated with negative symptoms
Reduced processing of information in the ___ and ___ is associated with hallucinations
Who stated this
Ventral striatum
Temporal and cingulate gyri
Simon et al. (2015)
what does lower than usual levels of information processing suggest
That cognition is likely to be impaired
Who discovered two types of dysfunctional thinking and what are they
Christopher Frith et al. (1992)
Metarepresentation dysfunction
Central control dysfunction
What is Metarepresentation dysfunction
The cognitive ability to reflect on thoughts and behaviour
What would dysfunction in Metarepresentation cause and what does it explain in schizophrenia
It would disrupt our ability to recognise our own actions and thoughts as being carried out by ourselves rather than someone else.
Hallucinations of hearing voices and delusions like thought insertion (positive)
What is central control dysfunction
The cognitive ability to suppress automatic responses while we perform deliberate actions
How is central control dysfunction expressed as a symptom
Speech poverty and thought disorder could result from the inability to suppress automatic thoughts and speech triggered by other thoughts
What is one strength of the family dysfunction theory
Evidence linking it to schizophrenia
What are the studies that support family dysfunctions link to schizophrenia
John Read et al. (2005)
Morkved et al (2017)