Schizophrenia Flashcards
What are the 2 types of schizophrenia symptoms?
Positive and negative
What is a positive symptom?
Anything which is an addition to a normal experience
What is a negative symptom?
Anything which is a reduction or loss of normal behaviour
Name 3 positive symptoms and what they mean
Hallucinations - Unreal perceptions of the environment
Delusions - Strange beliefs that seem real to the person with schizophrenia but aren’t real
Catatonic behaviour - Abnormal and bizarre motor movements
Name 3 negative symptoms and what they mean
Alogia - speech poverty
Avolition - Can’t work towards goals (lack of motivation)
Disorganised thinking - Can’t follow a train of thought
ICD vs DSM
ICD = Europe
DSM = USA
ICD needs 1 positive and 2 negative symptoms
DSM needs 2 general symptoms
What is symptom overlap? How does it relate to schizophrenia?
Schizophrenia has lots of symptoms shared with other disorders
Depression - avolition
Bi-polar - delusions
How do culture and schizophrenia interact?
Blacks and Hispanics are most likely to be diagnosed with it
This is because certain cultural practices may be misunderstood
How does comorbidity relate to schizophrenia
Schizophrenia is often co-morbid with other conditions
This make it more difficult to diagnose
Osorio
Gave 180 people the dsm5
In pairs, they had to diagnose individuals
Achieved an inter-rater of 0.97 and a test-retest of 0.92
Cheniaux
2 psychiatrists diagnosed 100 people with the ICD and DSM
Very low agreement
ICD = 68
DSM = 39
Buckley
Co-morbid:
50% - depression
47% - substance abuse
23% - OCD
Diagnosis of schizophrenia evaluation
Very reliable - Osorio
Its co-morbid with other conditions so we don’t fully understand it (Buckley)
Shows symptom overlap making it hard to diagnose
Culturally biased but diagnosis should be unbiased
Lacks validity (Cheniaux)
What are the biological explanations of schizophrenia?
Genetics
Dopamine hypothesis
Neural correlates
Gottesman
Large scale study on schizophrenia running in families
General population - 1%
Parents - 6%
MZ twins - 48%
Hilker
Shown the genetic explanation through twin studies
33 concordance in MZ twins
7 in DZ twins
MZ share more genes so more likely to have schizophrenia
What is a candidate gene?
A specific gene which causes something
How is schizophrenia found in DNA?
Its polygenetic so more than 1 gene
Ripke
37000 suffered
113000 controls
108 genetic variations that could cause schizophrenia
Genetic explanations of schizophrenia evaluation
Doesn’t take into account how people without a family history of schizophrenia develop the disease - however this could be explained via mutation
Very deterministic - the illness is written into DNA. C.A. As identical twins share 100% of their genes, it would be expected that the concordance rate for schizophrenia would be 100% if it was purely genetic. As it is only around 50%, this suggests other influences are playing a part.
Provides real world application (embryo screening) - however this is unethical selecting desirable traits in babies
It may be that the increased concordance rates in the Gottesman study were due to the increased chance of sharing the same environment as the person with schizophrenia. For example, identical twins share the same environment (and may be treated similarly), whereas first cousins would not. This means that it can’t be concluded that genetics has caused schizophrenia
What does the dopamine hypothesis of schizophrenia suggest
Over or under production of dopamine can affect different brain regions and their functions
What is hyperdopaminergia and what are it effects?
Too much dopamine is produced which affects Brocas area and then leads to alogia. Also linked to auditory hallucination
What is Hypodopaminergia and what are its effects
The under production of dopamine. This affects the prefrontal cortex which is involved in decision making and problem solving - these processes often decline in sufferers
Goldman-Rakic
Identified a role for low levels of dopamine in the prefrontal cortex - links to negative symptoms of schizophrenia e.g. alogia and affective flattening
How do drugs that block dopamine receptors effect schizophrenia
They reduce symptoms (not cure)
Phenothiazine
Block dopamine receptors and reduce schizophrenia symptoms
L-dopa
Parkinsons treatment
Increases dopamine in the brain and can bring out schizophrenia symptoms
Amphetamines
Increase dopamine levels and cause the development of schizophrenia symptoms in users
Dopamine hypothesis evaluation
Led to drug development such as Phenothiazine
Tauscher found antipsychotics that reduce the role of dopamine will alleviate schizophrenia symptoms and reduce the occurrence of positive symptoms
Very reductionist - evidence that other biological factors play a role e.g. genetics and also psychological factors such as family. A more holistic approach may be more favourable
Drugs don’t work for all users - this is an issue as if schizophrenia is caused by dopamine levels, drugs should work for everyone
What does neural correlates mean?
Relating brain structure or function to schizo
What brain area is associated with reward
The ventral striatum
Juckel
Measured activity levels in the ventral striatum in schizophrenic people
Lower level of activity than the controls
The less activity, the worse the negative symptoms
Allen
Scanned brains of those with auditory hallucinations
Compared to controls
Played pre-recorded speech to participants
They had to identify speech as their own or others
Sufferers experienced lower level of activation in their superior temporal gyrus and anterior cingulate gyrus
Neural correlates evaluation
The research is all correlational - there is a relationship between brain region and certain symptoms of schizo however we are still lacking cause and effect
Application - way to diagnose sufferers as if there is a change in brain structure, this could be used to identify the disorder
Buchsbaum used PET scans to find reduced cerebral blood flow in schizophrenic patients compared to controls. This can explain the arise of catatonic symptoms.
Current research only explains a few schizophrenia symptoms such as alogia and auditory hallucinations. Doesn’t explain other symptoms suggesting another approach may be better. Opposing argument …
What are the 3 explanations of family dysfunction
Schizophrenogenic mother
High EE (expressed emotion)
Double bind
What does having a schizophrenogenic mother mean?
A psychodynamic explanation
Cold and rejecting mothers
Atmosphere of tension and secrecy
Child is therefore distrusting and paranoid
Develops delusions and eventually schizophrenia
What does double bind mean (schizophrenia)
No matter what a child does, they can’t win as parents give mixed messages and inconsistent standards are imposed on them
The child wants to do the right thing but fears being wrong.
A child caught in a double-bind may develop schizophrenic symptoms such as paranoia and disorganised thoughts e.g. Am I doing the right thing?
When they make an error, they are punished through withdrawal of love
The world is confusing, unpredictable and dangerous