Schizophrenia Flashcards
(39 cards)
What is Schizophrenia?
Is the most common psychotic disorder.
About 1% of the population have it.
15-35 years it is most common.
What model is used to diagnose Schizophrenia?
The Diagnostic and Statistical Manual of Psychiatric Disorders (DSM), We are currently using the 5th edition, DSM-V.
What are the 4 main symptoms of Schizophrenia?
Delusions (fake beliefs)
Speech poverty
Hallucinations (false perceptions)
Avolition
What is Avolition?
A symptom of SZ, Is the reduction of, or inability to initiate and persist in, goal-directed behaviour (e.g. sitting in the house for hours every day, doing nothing.
Give two positive and two negative symptoms of Schizophrenia?
Positive (adding)
- Hallucinations
- Delusions
Negative (taking away)
- Avolition
- Speech poverty
What is Test-retest Reliability?
The doctor must reach same conclusion about the patient at two different times so the patient is not labelled wrongly or re-diagnosed.
What is inter-rater reliability?
The extent to which different assessors agree on their assessments. Doctors must agree and come to the same conclusions for research to have high inter-rater reliability.
Who is the researcher for inter-rater reliability and what was his study?
Cheniaux et al (2009) Had two psychiatrists independently diagnose 100 patients using the DSM criteria and the ICD criteria. One doctor diagnosed 26 patients with SZ using the DSM and 44 using the ICD. The other doctor diagnosed 13 using the DSM and 24 using the ICD.
Give a negative evaluation point for Reliability?
Cultural differences in diagnosis.
Copeland (1971) Gave 134 US and 194 British Psychiatrists a description of a patient. 69% of Us psychiatrists diagnosed SZ but only 2% of the British ones did.
This suggests there is a significant variation between countries.
Describe Rosenhams study of Reliability?
Rosenham conducted a study where normal healthy people presented themselves to a hospital saying they had unfamiliar voices saying “empty, hallow and thud”. They were all diagnosed with Schizophrenia. The people admitted they did not have any symptoms and non of the staff recognised they had no schizophrenic symptoms. Rosenham warned other hospitals he was gonna repeat it which resulted in 21% patients not diagnosed.
What is the difference between reliability and validity?
Reliability is the consistency of a measuring tool e.g. the DSM or other tests used in the diagnosis.
Validity is the extent to which diagnosis is accurate and meaningful. Must represent something real and tools must measure correctly.
What is meant by Gender Bias as an evaluation point for Validity?
Gender bias - Boverman et al (1970) Found US clinicians believed mentally healthy adults were “male” therefore women were less mentally healthy.
What is meant by Symptom Overlap as an evaluation point for Validity?
Many Schizophrenic symptoms are found in other disorders like depression. Read (2004) states most Schizophrenic people have sufficient symptoms of other disorders (they could receive atleast one other diagnosis).
What is meant by co-morbidity as an evaluation point for Validity?
Co-morbidity is the extent that 2 or more conditions occur. Schizophrenia occurs alongside, Depression, Anxiety, Substance abuse.
Buckley et al (2009) estimated co-morbid depression occurs in 50% of patients, and 47% also have life time diagnosis of co-morbid substance abuse.
Describe what is meant by Schizophrenia being Polygenic?
It means that the condition is influenced by multiple genes, each contributing a small amount to the overall risk of developing the disorder. In other words, schizophrenia is not caused by a single gene, but by a combination of many different genes interacting with each other and the environment.
What were Gottesman’s findings on genetics influencing Schizophrenia?
Gottesman found that children with two biological parents who have Schizophrenia had concordance rates of 46% however children with one biological parent with schizophrenia had a rate of 13%. He also found that individuals who have a sibling with schizophrenia had a rate of 9%.
What do family studies suggest about genetics being an influence for Schizophrenia?
Family studies show genes do play an important role, but if genes were the only cause of Schizophrenia then surely concordance rates would be 100%. Theory could be seen as biologically deterministic as it presents no influence of any other factors other than genetics. Researches now accept that SZ concordance rates in families may be more to do with the environment and other factors.
What does Twin studies show us about genetics being an influence of Schizophrenia?
If Monozygotic twins (100%) are more concordant than Dizygotic twins (50%) then this suggests the greater similarity due to genetics.
Joseph - points out that Monozygotic twins are treated much more similarly therefore have more of a similar environment.
Gottesman (1991) found that as genetic similarity increase so does the concordance rate of SZ. He found that Dyzigotic twins (sharing 50% of their genes) had a concordance rate of 17%, whereas monozygotic twins (sharing 100% of genes) had a concordance rate of 48%.
What do Adoption studies show us about genetics being an influence of Schizophrenia?
Tienari et al found that 164 adoptees whose mothers had SZ, 6.7% also was diagnosed with SZ compared to 2% of 197 control adoptees born to non Schizophrenic mothers.
Give evaluation points for Twin studies (biological explanation)?
The fact that the concordance rate for twins is not 100% means that
schizophrenia cannot be accounted for by genetics alone
Sample sizes of such twin studies is always going to be very small so therefore
it is difficult to generalise to the general population.
Give evaluation points for Family studies (biological explanation)?
Gottesman (1991) found that children with two biological parents with
schizophrenia had a concordance rate of 46%, children with one schizophrenic parent had a rate of 13% and siblings had a concordance
rate of 9%. (compared to a 1% chance for the general population).
Give evaluation points for Adoption studies (biological explanation)?
Tienari et al. (2000) found that of 164 adoptees whose biological mothers
had been diagnosed with Schizophrenia, 6.7% also received a diagnosis,
compared to just 2% of the 197 control adoptees (born to
non-schizophrenic mothers).
What is the role of dopamine as a Schizophrenia explanation?
Messages from neurons that transmit dopamine fire too easily or too often leading to hallucinate and delusions.
SZ patients are said to have too many D2 receptors.
An excess of neurotransmitters dopamine in certain regions of the brain is associated with positive symptoms of SZ.
What is Hyperdopaminergia?
Hyper - Is the original version of the dopamine hypothesis focused on high levels of dopamine in the subcortex i.e. central areas of the brain. An excess of dopamine receptors in the Broca’s area (speech production) may be associated with speech poverty and auditory hallucinations.
