Schizophrenia Flashcards
SCHIZOPHRENIA
What is schizophrenia?
A psychotic disorder marked by severely impaired thinking, emotions, and behaviour
CLASSIFYING MENTAL DISORDERS
Which manuals are used to classify mental disorders?
The DSM V or the ICD 10
CLASSIFYING MENTAL DISORDERS
What do both manuals require?
Symptoms to be present for a month
CLASSIFYING MENTAL DISORDERS
What does the DSM V require?
A more specific criteria; 2 or more symptoms
CLASSIFYING MENTAL DISORDERS
What does the ICD 10 require?
A broader approach to diagnosis
CLASSIFYING MENTAL DISORDERS
Which culture uses the DSM V?
America
CLASSIFYING MENTAL DISORDERS
Which countries use the ICD 10?
Anywhere that isn’t America
CLASSIFYING MENTAL DISORDERS
What type of functioning does schizophrenia include?
Excessive normal functioning
CLASSIFYING MENTAL DISORDERS
Describe diagnosis discrepancies between men and women
Women diagnosed 10 years later on average than men, who are most commonly diagnosed between 18 and 21
POSITIVE SYMPTOMS
What is a positive symptom of Schizophrenia?
Ones that enhance the typical experience of sufferers, and occurs in addition to their normal experiences
POSITIVE SYMPTOMS
Define a hallucination
A distorted view/perception of a real stimulus or stimulus that has no basis in reality
POSITIVE SYMPTOMS
What are the four types of hallucination?
- Auditory
- Visual
- Tactile
- Olfactory
POSITIVE SYMPTOMS
Define a delusion
A set of beliefs with no basis in reality, for example believing members of the royal family are trying to kidnap you
NEGATIVE SYMPTOMS
Define a negative symptom
Loss of normal functions due to increased serotonin and low levels of dopamine
NEGATIVE SYMPTOMS
Define alogia
Speech poverty, a frequent inability to find the right words
NEGATIVE SYMPTOMS
Define avolition
A reduction in interest
NEGATIVE SYMPTOMS
Define affective flattening
Flat emotions, such as no excitement at christmas or grief over a deceased pet
NEGATIVE SYMPTOMS
Define anhedonia
Physical or social loss of pleasure
CULTURAL BIAS AND RELIABILITY
What is the biggest sign of cultural bias?
The presence of two different diagnostic manuals
CULTURAL BIAS AND RELIABILITY
What did Copeland investigate?
Cultural differences in the diagnostic process
CULTURAL BIAS AND RELIABILITY
How did Copeland investigate cultural differences?
134 US psychiatrists V 194 GB psychiatrists given a definition of a patient
CULTURAL BIAS AND RELIABILITY
What were the results of Copeland’s study?
US 69% diagnosed schizophrenia
GB 2% diagnosed schizophrenia
CULTURAL BIAS AND RELIABILITY
What do Copeland’s findings suggest?
The diagnostic process is not reliable bc there are two different diagnostic manuals. People may not be given suitable treatment due to a wrong diagnosis.
RELIABILITY IN DIAGNOSIS
What must diagnosis be?
Repeatable - clinicians must be able to reach the same conclusions at two points in time (aka inter rater reliabilty)
RELIABILITY IN DIAGNOSIS
How is inter rater reliability measured?
The kappi score
RELIABILITY IN DIAGNOSIS
What is a score of 1?
Perfect inter rater reliability
RELIABILITY IN DIAGNOSIS
What is a score of 0?
No agreement
RELIABILITY IN DIAGNOSIS
What is generally considered a good score?
0.7
RELIABILITY IN DIAGNOSIS
What was the DSM V’s kappi score?
Only 0.4
RELIABILITY IN DIAGNOSIS
What does the DSM V’s kappi score show?
There is significant variation between countries when diagnosing schizophrenia
VALIDITY: SYSTEM OVERLAP
What did Ellason and Ross point out?
People w schizophrenia have less schizophrenic symptoms than those diagnosed with D.I.D
VALIDITY: SYSTEM OVERLAP
What did Read find?
People w schizophrenia have sufficient symptoms of other disorders
VALIDITY: COMORBIDITY
What does Buckeley et al estimate?
50% of patients w schizophrenia have depressive symptoms
VALIDITY: COMORBIDITY
What did Swets et al find?
12% of patients w schizophrenia have OCD symptoms
VALIDITY: COMORBIDITY
What do the studies suggest?
It’s very common amongst all patients w schizophrenia to be misdiagnosed. Reduced the validity of diagnosis
GENDER BIAS
How did Coring and Powell investigate gender bias?
Randomly selected 290 male and female psychiatrists to read two case vignettes of patients behaviour and were asked to give a judgement using standard diagnostic criteria
GENDER BIAS
What were Coring and Powell’s findings
- Male or unlabelled patient: 56%
- Female patient: 20%
GENDER BIAS
What does Coring and Powell’s results suggest?
The diagnosis of Schizophrenia is influenced by the gender of the patient
BIO EXP FOR SZ: GENETICS NUMBER ONE
What is the key assumption?
Looking at sz from a biological basis. This can be explained by genetics. A degree of inheritability.
BIO EXP FOR SZ: GENETICS NUMBER ONE
Describe family studies
Gottesman investigated the genetic prevalence amongst the family. General pop: 1%, parents 6%, siblings 9%
BIO EXP FOR SZ: GENETICS NUMBER ONE
What do family studies suggest?
More genes you share more likely to inherit sz
BIO EXP FOR SZ: GENETICS NUMBER ONE
Describe adoption studies
Tienari found 6.7% of children adopted w sz biological mother had been diagnosed w schizophrenia themselves. Opposed to 2% of children diagnosed w no sz mother
BIO EXP FOR SZ: GENETICS NUMBER ONE
What do adoption studies suggest?
Genetic predisposition overrides environmental factors
BIO EXP FOR SZ: GENETICS NUMBER ONE
What percentage of DNA do twins share?
DZ (50% of same DNA) MZ (100% of same DNA)
BIO EXP FOR SZ: GENETICS NUMBER ONE
Describe twin studies
Gottesmas carried out meta-analysis and reviewed 40 studies that had investigated family history of sz. DZ twins 17% MZ twins 48%
BIO EXP FOR SZ: GENETICS NUMBER ONE
What do twin studies suggest?
Genetic predisposition - more genes more likely
BIO EXP FOR SZ: GENETICS NUMBER ONE
AO3 scientific credibility
- Research evidence providing empirical facts
- Joseph found 40% for MZ and 7.4% for DZ
- Scientific credibility due to research
BIO EXP FOR SZ: GENETICS NUMBER ONE
AO3 deterministic
- Overly stating role of nature
- Highest concordance rate 48% MZ, strongest genetical link one can have
- Leaves room for other explanations
- OCD 87% which further belittles this figure
- Biology not only explanation
BIO EXP FOR SZ: GENETICS NUMBER ONE
AO3 methodology issues
Twins are small sample size already, then a set of twins one w schizophrenia (at least) reduces even more. Can you therefore generalise?
BIO EXP FOR SZ: GENETICS NUMBER ONE
AO3 methodology issues
Twins are small sample size already, then a set of twins one w schizophrenia (at least) reduces even more. Can you therefore generalise?
BIO EXP NEUROTRANSMITTERS
What is the key assumption?
Biological basis for sz due to biochemical imbalances
BIO EXP NEUROTRANSMITTERS
What does the dopamine hypothesis claim?
Having an excess of dopamine in central regions of the brain is associated w positive symptoms of sz. It is thought this is due to abnormally high levels of D2 receptors on the receiving neuron
BIO EXP NEUROTRANSMITTERS
What does the dopamine hypothesis result in?
More dopamine binding so more neurons firing
BIO EXP NEUROTRANSMITTERS
What does amphetamine do?
Increase dopamine activity, leading to an increase in sz symptoms
BIO EXP NEUROTRANSMITTERS
How does amphetamine lead to an increase in sz symptoms?
Stimulating nerve cells containing dopamine, causing the synapse to be flooded w the neurotransmitter
BIO EXP NEUROTRANSMITTERS
What did Grilly 2002 say?
When parkinson sufferers take drug called ‘l-dopa’ which raises d levels, it causes them to develop sz like symptoms. This suggests there is a relationship bt dopamine and sz
BIO EXP NEUROTRANSMITTERS
Describe antipsychotic drugs
Block activity of dopamine in brain. By reducing the activity in neural pathways which use dopamine, you eliminate the symptoms
BIO EXP NEUROTRANSMITTERS
Who did the revised dopamine hypothesis
Davis and Kahn
BIO EXP NEUROTRANSMITTERS
What did Davis and Kahn propose?
Proposed positive symptoms due to an excess dopamine in the subcortical areas of the brain. The negative symptoms arise from a deficit of dopamine in pre-frontal cortex