Schizophrenia definition
Correlation of unrelated symptoms
What are the two classifications of schizophrenia?
Classification of schizophrenia
ICD-10
DSM-5
What is ICD-10
Classification of schizophrenia
Two or more negative sympotoms for one month or longer ex; avolition and speech poverty
UK
Recognises subtypes
What is DSM-5
Classification of schizophrenia
one positive symptom must be present, for at least one month,(e.g. delusions, hallucinations)
US
What is a positive symptom
Positive symptoms of schizophrenia, including hallucinations and delusions
An additional experience beyond those of ordinary existence
Hallucination= Unusual sensory, no basis in reality, auditory or visual
Delusions =Irrational false beliefs, no basis in reality, Persecution (harrassed), Control by external e.g. aliens
What are negative sympotoms
A loss of usual abilities and experiences.
Avolition loss of motivation to carry out everyday tasks and difficulty to begin or keep up with goal-directed activity, poor hygeince
Speech poverty, reduction in the amount and quality of speech
What is reliability?
Reliability and validity in diagnosis and classification of schizophrenia
Reliability refers to consistency.
This refers to whether we can gain consistent results when classifying and diagnosing Schizophrenia
Measured by inter-rater reliability
What is validity?
Reliability and validity in diagnosis and classification of schizophrenia
refers to accuracy
the extent to which we are measuring what we intend to measure (schizophrenia).
What is the study to Reliability and validity?
Reliability and validity in diagnosis and classification of schizophrenia
Cheniaux (2009) asked two psychiatrists to diagnose the same 100 patients using the DSM and ICD.
One psychiatrist diagnosed 26 according to DSM and 44 according to ICD.
The other diagnosed 13 according to DSM and 24 according to ICD.
This shows poor inter-rater reliability as one psychiatrist diagnosed almost double the amount than the other psychiatrist.
Moreover, it demonstrates poor reliability in the classification of schizophrenia as both psychiatrists diagnosed almost double the amount of patients using the ICD than the DSM, which also calls in to question the validity of the diagnosis.
What is system overlap?
Reliability and validity in diagnosis
This is where two or more conditions share similar symptoms.
For example, both schizophrenia and depression involve negative symptoms such as avolition.
What is Co-morbidity
Reliability and validity in diagnosis
This is where two illnesses/conditions occur at the same time.
Schizophrenia is commonly diagnosed with other conditions such as depression and/or OCD
Evaluation for reliability and validity
Reliability and validity in diagnosis and classification of schizophrenia
limitation
‘Symptom overlap’.
This is where two or more conditions share similar symptoms.
For example, both schizophrenia and depression involve negative symptoms such as avolition.
This questions the validity and reliability of the classification and diagnosis of schizophrenia
An individual may be diagnosed with the wrong disorder.
This is an issue as doctors may not be diagnosing schizophrenia correctly,
therefore individuals may not recieive appropriate treatment.
Evaluation for reliability and validity
Reliability and validity in diagnosis and classification of schizophrenia
limitation
Co-morbidity’.
This is where two illnesses/conditions occur at the same time.
For example, Buckley et al (2009) concluded that 50% of patients diagnosed with schizophrenia also have a diagnosis of depression and 23% of patients diagnosed with schizophrenia are diagnosed with OCD. T
his questions the validity and reliability of classification and diagnosis of schizophrenia,
because they may be better seen as one condition
doctors may diagnose the wrong condition.
Evaluation for reliability and validity
Reliability and validity in diagnosis and classification of schizophrenia
limitation
Gender bias in diagnosis.
Since the 1980s men have been diagnosed with schizophrenia more often than women.
This may be because men are more genetically vulnerable to developing schizophrenia than women.
However, it could be because females with schizophrenia typically function better than men
being more likely to work and have good family relationships therefore their symptoms may be masked by good interpersonal skills (Cotton et al).
This questions the validity and reliability
as women who share similar symptoms as men may not receive the same diagnosis as their symptoms seem mild.
What are the two explanations of schizophrenia?
biological explanations
psychological explanations
What are the three features of the biological explanations?
explanations of schizophrenia
Genetics
Neural correlates
Dopamine hypothesis
What is the genetic theory?
Biological explanation of schizophrenia
Explanations of schizophrenia
SZ hereditary and polygenic
Predisposition due to maladaptive candidate genes
PCM1
Each gene increases the vulnerability
A01 study for genetic theory.
Biological explanation of schizophrenia
Explanations of schizophrenia
Gottesman (1991) studied 40 twins
and found that the concordance rate for monozygotic twins was 48% and only 17% for dizygotic twins
Therefore, the closer the genetic link to somebody with schizophrenia, the more chance of developing schizophrenia.
Genetic theory evaluation
Biological explanation of schizophrenia
Explanation of schizophrenia
Research to support Tienerry.
He studied 155 adopted children who had biological mothers with schizophrenia
found that they had a concordance rate of 10% compared to 1% in adopted children without schizophrenic parents.
This provides significant support for the role of genetics as an explanation of schizophrenia
Social Learning Theory's role could not have been a factor as the children were adopted.
What is neural correlates of brain structure?
Biological explanations of schizophrenia
Explanations of schizophrenia.
Enlarged ventricles
Raz and Raz compared ventricle size to those with schizophrenia to those of control group.
Associated with damage to prefrontal (decision making)
Leads to avolition
Evaluation for neural correlates brain structure
Biological explanations of schizophrenia
Explanations of schizophrenia.
strength
Suddath et al
Research to support
He used MRI scans to investigate the brain structure of MZ twins in which one twin had schizophrenia
the schizophrenia twin was found to have larger ventricle
suggesting enlarged ventricle do play a role in determining the likelihood of schizophrenia developing
What is neural correlates dopamine hypothesis
Biological explanations of schizophrenia
Explanations of schizophrenia.
Neurotransmitters work differently in those with SZ
Both neural correlates exist in different regions
Hyperdopanminergia
Hypodopaminergia
What is Hyperdopaminergia? Dopmine hypothesis
Biological explanations of schizophrenia
Explanations of schizophrenia.
Subcortex
High dopamine activity in Broca's area
Auditory hallucinations
What is Hypodopaminergia? Dopmine hypothesis
Biological explanations of schizophrenia
Explanations of schizophrenia.
Cortex
Low dopamine in prefrontal cortex (decisions)
Avolition
Overall evaluation of the biological explanation of schizophrenia
Biological explanations of schizophrenia
Explanations of schizophrenia.
strength
scientific methods
based on objective and emperical methods
such as gene mapping and brain scans which are used to identify specific genes or area of schizophrenia (enlarged ventricles)
therefore increases the overall internal validity
thus raising psychology scientific status
Overall evaluation of the biological explanation of schizophrenia
Biological explanations of schizophrenia
Explanations of schizophrenia.
limitation
biological determinism
theory states an individual is controlled by internal factors
fir example high dopamine (hyperdopaminergia) in the subcortex which causes auditory hallucinations
neglets the role of free will
no control over theor schizophrenic behaviour
families can feel guilty for passing the gene
limiting the biological explanation of schizophrenia
Overall evaluation of the biological explanation of schizophrenia
Biological explanations of schizophrenia
Explanations of schizophrenia.
strength
practical applications
schizophrenia is caused by an inbalance of dopamine has led to the treatment of drug therapies such as typical and atypical antipsychotics
effective in treating schizophrenia by balancing levels of dopamine in the patients brain and reducing symptoms such as hallucinations
important part of applied psychology
as it helps treat people in the real world
Overall evaluation of the biological explanation of schizophrenia
Biological explanations of schizophrenia
Explanations of schizophrenia.
limitation
family dysfunction
due to faulty coomunciation patterns such as schizophrenic mother
leads to distruct that later develops into paronoid delucions rather than delucions being due to levels of dopamine
therefore the biological explanantion of schizophrenia is not the only explanation that can be considered
What are psychological explanation of schizophrenia.
family dysfunction
cognitive explanations including dysfunctional thought processing
What is family dysfunction?
Psychological explanations for schizophrenia.
individual develops schizophrenia because they are raised in a dysfunctional family environment
They are dysfunctional in the way that they communicate with each other; high levels of tension and arguments
What is family dysfunction broken down into?
Psychological explanations of schizophrenia.
schizophrenigenic mother
Double bind communication
Express emotion
What is schizophrenogenetic mother?
Family dysfunction
Psychological explanations for schizophrenia.
The mother is cold,controlling,rejecting,emotionally unresponsive
Builds a family based on tension and secrecy
leads to distrust and develops to paranoid delusions +
What is expressed emotion?
Family dysfunction
Psychological explanations for schizophrenia.
High levels of expressed emotion; verbal criticism and occasional violence towards patient
hostility towards patient
anger, rejection
emotional over-involvement in their life
causes stress to the patient and results in relapse
What is double bind communication?
Family dysfunction
Psychological explanations of schizophrenia
Verbal not the same as non-verbal
Confusion = no trust in themselves
Anxious
Withdraw from social contact
Avolition & paranoid delusions