Schizophrenia Flashcards
What is a delusion?
An unshakeable belief in something that is very unlikely, bizarre or obviously untrue.
What is an hallucination?
Hearing or seeing things which are not there.
What is avolition?
The reduction of, or the inability, to initiate and persist in goal related behaviour
What is Alogia?
Lessening of speech fluency and productivity
What is reliability?
Consistency of the measuring instrument such as a questionnaire
What is validity?
Whether a measuring tool measures what it sets out to measure
What is comorbdity?
Refers to the extent that two (or more) conditions co-occur.
How can reliability be tested?
Reliability of such questionnaires or scales can be measured in terms of whether 2 independent assessors give similar diagnosis (inter-rater reliability) or whether tests used to deliver these diagnoses are consistent over time (test-retest reliability)
What is inter-rater reliability?
Whether 2 independent assessors give similar diagnosis
What is rest-retest reliability?
Whether tests used to deliver these diagnoses are consistent over time.
What are the two most widely used classification systems for diagnosis of schizophrenia?
DSM-IV and ICD-10
What are the differences between DSM-IV and ICD-10?
- Different time requirments2. Different factors considered3. Different subtypes
How are DSM-IV and ICD-10 differ in terms of time requirments?
DSM-IV require people to have one or more of the clinical characteristics for at least 6 months, whilst ICD-10 requires it to be apparent for 1 month.
What is the advantage of the ICD-10 over DSM-IV in terms of time requirements?
Sufferers do not have so much time in which they may me at risk to themselves and others. They also only have to live without help for one month before receiving diagnosis and appropriate treatment.
How does DSM-IV and ICD-10 differ in terms of the factors they consider?
DSM is multi-axial; various factors (bio, psychological, social) considered. It takes account the individual and the situation rather than merely the symptoms as it assess the suffer’s social functioning, such as poverty and physiological state of health. ICD-10 place the emphasis on first rank symptoms, and ignores the social functioning/context of the individual.
How does ICD-10 and DSM-IV differ in terms of subtypes?
ICD and DSM do not entirely agree on the number of subtypes of schizophrenia with the ICD suggest seven different subtypes and the DSM five.
What is the problem with ICD-10 and DSM-IV differing in terms of subtypes?
The reliability here is questioned as a sufferer could be diagnoses as one type of schizophrenic according to the DSM and a different type according to the ICD which could result in incorrect treatment.
Why could ICD-10 be considered more universal?
It can be applied to more diverse cultures at the World Health Organisation (creators of the ICD) are made up of representatives from 193 countries and therefore various cultures are represented.
What did Copeland (1971) find about cultural differences in early classification system?
Gave 124 US and 194 British psychiatrists a description of a patient. 69% of the US psychiatrists diagnosed schizophrenia. Only 2% of British psychiatrists diagnosed schizophrenia.
What was done to try and solve the cultural differences in early classification systems?
Prior to 1970’s there was a significant difference in prevalence rates of SZ in different countries. To eliminate diagnostic differences attempts were made to bring the two systems (ICD-10 and DSM-TR-IV) into line with one another. Became similar, not identical
What is the problem with the DSM system in terms of reliability?
Despite claims for increased reliability in DSM-III and later versions, 30 years later there is still little evidence that DSM is routinely used with high reliability by mental health clinicians.
What are some other diagnostic tools to help diagnose schizophrenia?
St Louis Criteria, Schneider criteria Research Diagnostic Criteria etc.
What is the difficulty with having multiple diagnostic tools?
It makes research comparisons difficult. Makes difficulty to describe what exactly is meant by SZ. If the catergories are poorly defined and arbitrary, consistent (reliable) diagnosis is likely to be low.
What study did Prescott (1986) do on the use of diagnostic tools?
Used various measures to assess attention and information processing in 14 chronic schizophrenics. Performance on these measures (using test-retest reliability) was stable over a 6 month period.
Why could the DSM-IV be considered culturally biased?
It was created by Americans for Americans. Behaviour in one culture may not be regarded as a symptom of SZ but according to DSM it is. Thus could lead to incorrect diagnosis and treatment.
Why did Crow (1985_ believe that SZ is too broad a term?
Because at least two very different conditions exist:Type 1 syndrome: Acute disorder characterised by positive symptomsType 2 syndrome: chronic disorder, negative symptoms.
What is the problem witht he use of Sub-types
Type 1 and Type 2 SZ respond very differently to psychological and biological treatment. Problem with division- people do not fit neatly into one category; blurred distinction between subtypes, soime people diagnosed in one category later develop symptoms from another, SZ has many different categories and symptoms
What is type 1 syndrome?
Acute disorder characterised by positive symptoms
What is type 2 syndrome?
Chronic disorder characterised by negative symptoms
How do treatments differ in success between type 1 and type 2 SZ?
Typical and Atypical phenothiazines have more success with relieving positive symptoms as does CBT.
Why might there be difficulties with reliability in diagnoses?
- The same patient may give different information to different doctors
What is the Inter-rater reliability of diagnosis like?
Exceptionally low, less than 50%. Thus people who are incorrectly diagnosed may be included in research which may result in invalid conclusions about the cause of the ‘illness’ and/or treatment.
What did Beck et al (1961) find?
Found that agreement on diagnosis for 153 patients (where each was assessed by two psychiatrists from a group of four) was only 54%. This was often due to vague criteria for diagnosis and inconsistencies in techniques to gather data. –
What did Whaley (2001) find?
found inter-rater reliability correlations in the diagnosis of schizophrenia as low as 0.11
What is the problem with the characteristic ‘delusions are bizarre’?
What seems bizarre to one psychiatrist might not seem bizarre to another. When 50 psychiatrists in the US were asked to differentiate between bizarre and non-bizarre delusions they produced inter-reliability correlations of only around +0.40
What did Cheniaux (2009) do?
investigated the inter-rater reliability of the diagnosis of schizophrenia according the DSM-IV and ICD-10. Although the inter-rater reliability was above +0.5 for both classification systems schizophrenia was more often diagnosed according to ICD-10 than DSM-IV criteria.
What are the aim of Rosenhan’s study?
To test the hypothesis that psychiatrists cannot reliably tell the difference between people who are sane and those who are insane.
What was the method of Rosenhan’s (1973) study?
8 people went to a psychiatric hospital and reported only 1 symptom- that a voice said only single words, like ‘thud’, ‘empty’ or ‘hollow’. When admitted they began to act ‘normally’.
What were the results of Rosenhan’s (1973) study?
All were diagnosed with suffering from SZ (apart from 1). The individuals stayed in the institutions for between 7 to 52 days.
What were the conclusion of Rosenhan’s (1973) study?
The reliability of the ability to detect the sane from the insane was proved to be inconsistent.
What is the problem with Rosenhan’s study?
It was conducted over 30 years ago. Since then manuals have been improved and diagnostic practice is very different. Also the ICD and DSM have been brought in line with one another and so are now similar.
What does Validity refer to in regards to diagnosis?
Refers to the extent that a diagnosis represents something that is real and distinct from other disorders and the extent that a classification system measures what it claims to measure.
How are reliability and validity linked?
Reliability and Validity are linked because if scientists cannot agree who has SZ (low reliability) then questions of what it actually is (i.e. validity) become essentially meaningless.
What is meant by comorbidity?
Comorbidity refers to the extent that two or more conditions co-occur. Psychiatric co-morbidities are common among patients with schizophrenia. These include substance abuse, anxiety and symptoms of depression.
What did Buckley et al (2009) estimate?
Estimates that comorbid depression occurs in 50% of patients and 47% of patients also have a lifetime diagnosis of comorbid substance abuse.
Why does comorbidity make things more difficult?
It makes diagnosis difficult and also treatment difficult to advise. Also, as a consequence of being diagnosed with SZ they receive a low standard of care which affects their prognosis.
What might poor levels of functioning in many SZ be a result of?
Could be less the result of their psychiatric disorder and more to do with their untreated comorbid physical disorder.
What did Weber et al (2009) find?
Examined nearly 6 million hospital discharge records to calculate comorbidity rates. Found psychiatric and behaviour related diagnosis accounted for 45% of comorbidity. Many patients diagnosed with SZ also had non-psychiatric problems, such as hypothyroidism, asthma, hypertension and diabetes. Concluded that being diagnosed with a psychiatric disorder meant patient receive a lower standard of medical care, which adversely affects their prognosis.
What is meant by schizophrenia like disorder?
ICD/DSM include schizophreniform psychosis, schizoaffective disorder, schizotypal disorder, schizoid personality disorder- many variations-, where individuals diagnosed present SZ type symptoms but do not meet criteria.
What is the problem with Shizophrenia-like disorders?
Doubt about the validity of some of these classifications, as the boundary between them is blurred.
What did Ellason and Ross argue?
They point out that many people with dissociative identity disorder have more SZ symptoms than people diagnosed as being schizophrenia.
What did Klosterkotter et al (1994) find?
Assessed 489 admissions to a psychiatric unit in Germany to determine whether positive or negative symptoms were more valid for a diagnosis. They found positive symptoms were more useful than negative.
What is the problem with Prognosis for SZ?
People with SZ rarely share the same symptoms or the same outcomes. A diagnosis of SZ therefore has little predictive validity.
What are some of the prognosis percentages for SZ?
20% full recovery10% significant improvement30% some improvement with lapses
What is the problem with the social stigma that surrounds SZ?
A system for diagnosing schizophrenia cannot be considered accurate if many cases go undiagnosed- due to certain social stigmas and repercussions attached to diagnosing someone with schizophrenia.
Where is SZ more likely to be undiagnosed due to social stigma?
Japan where SZ literally translates to “disease of the disorganised mind”
What did Kim and Berrios (2001) find?
They found that in Japan the idea of a “disorganised mind” is so stigmatised that psychiatrists are reluctant to tell patients of their condition. As a result only 20% are aware of it, and the rest are left undiagnosed.
What is the problem with labelling someone with a mental illness?
They have to disclose that information in certain situations such as job interviews, and they risk carrying the stigma of their condition for the rest of their lives.
What are the cultural variations in SZ?
It occurs across culturals, but in USA/UK it is more frequent among African American and African-Carribean populations.
Why could there be cultural variations in the diagnoses of SZ?
Could reflect greater genetic vulnerability, psychosocial factors, minority groupings or misdiagnosis. Clinicals could misinterpret cultural differences in behaviour and expression as symptoms. Doctors don’t understand black culture and misdiagnose SZ.
How do Psychiatrists in Pakistan, China and India differ from the West?
They think that the West place too much emphasis on separation of mind and body.
What is schizophrenia?
It is characterised by a profound disruption of cognition and emotion, which affects language, thought, perception and sense of self.
What are the prevalence rates of schizophrenia?
The lifetime prevalence of SZ is 1%. Men are more likely to suffer. The onset is typically in late adolescence and early adulthood.
What are positive symptoms?
Those that appear to reflect an excess or distortion of normal functions
What are negative symptoms?
Those that appear to reflect a diminution or loss of normal functions.
What are the positive symptoms of SZ?
- Delusions (paranoia, grandiosity)2. Experiences of control- thoughts and actions are believed to be under external control3. Auditory hallucinations- bizarre, unreal perceptions, usually auditiory4. Thought disturbance and disordered thinking 0thoughts have been inserted or withdrawn from the mind5. Language impairments6. Disorganised behaviour
What are the positive symptoms of SZ?
- Reduction in range and intensity of emotion expression, including facial expression, tone of voice etc. 2. Avolition- reduction or inability to take part in goal directed behaviour3. reactivity is not expected4. Thought blocking5. Asocial behaviour6. Emotional blunting7. Alogia- poverty of speech, lessening of speech fluency and productivity.
What is paranoid type?
(35-40%-less severe) Preoccupation with one or more delusions or frequent auditory hallucinations. No disorganised speech, disorganised or cataonic behaviour, or flat or inappropriate affect.
What is catatonic type?
(10%) Immobility or stpor excessive motor activity that is apparently purposeless, extreme negativism, strange voluntary movement as evidenced by posturing, stereotyped movements, prominent mannerisms, or prominent grimacing.
What is undifferentiated type?
(20%) Variation between symptoms, not fitting into a particular type.
What is residual type?
(20%) Absence of prominent delusions, hallucinations, disorganised speech and grossly disorganised or catatonic behaviour. Plus presence of negative symptoms or two or more symptoms listed in criterion A for SZ.
What is disorganised type?
(10%) Must have all; disorganised speech, disorganised behaviour, flat or inappropriate affect and not meet the criteria for catatonic type.
What is the DSM?
Diagnostic and statistical Manual of Mental Disorders) is produced by the American Psychiatric association. It contains a list of symptoms for each disorder and guidelines for clinicians who make diagnosis.
What is the ICD?
International Classification of Diseases) is produced by the World Health Organisation for both physical and mental illnesses. Its aim is to follow the epidemiology of diseases worldwide.
What is Schizophrenia?
It is characterised by a profound disruption of cognition and emotion, which affects language, thought, perception and sense of self.
What is the prevalence of SZ?
The lifetime prevalence is 1%. Men are more likely to suffer than women. The onset is typically in late adolescence and early adulthood.
How does the prevalence of SZ support a biological view?
Prevalence of schizophrenia is the same all over the world (about 1%). Risk rises with degree of genetic relatedness. This supports a biological view as prevalence does not vary with environment.
What did Kendler et al find about biological explanations for schizophrenia?
Found that 1st degree relatives of those with schizophrenia are 18 times more at risk than the general population.
What study did Kety et al do on biological explanations for schizophrenia?
Identified 207 offspring of mothers diagnosed with schizophrenia, along with a matched control of 104 children, matched on age, gender, parental socio-economic status, and urban/rural residence. Children aged 10-18 at start of study. SZ diagnosed in 16.2% of high risk group compared to 1.9% in control group.
How can twin studies help to demonstrate the impact of genetics on Schizophrenia?
Both identical (MZ) and fraternal (DZ) twins share the same environment, but only MZ twins have identical genetics- if schizophrenia is genetically related, the concordance rate of SZ should be much higher in MZ twins.
What did Gottessman and Shields find about biological explanations for SZ?
Used the Maudsley twin register and found 58% (7/12 MZ twins raised apart) were concordant for SZ.
What is the issue with genetics as an explanation for SZ?
- No twin study has yet shown 100% concordance in MZ twins. 2. Studies conducted so far don’t tell us which genes might be important for the transmission of SZ.
Who developed the dopamine hypothesis?
Comer
What is the dopamine hypothesis?
Dopamine neurons play a key role in guiding attention, so it is thought that disturbances in this process may lead to the problems of attention and thought found in people with schizophrenia.
How do Dopamine substitutes support the Biochemical explanation?
Dopamine substitutes such as L-Dopa increase the positive symptoms of SZ. L-Dopa is used to treat Parkinson’s disease which is characterised by a lack of dopamine. Too much L-Dope produces psychotic symptoms in Parkinson’s patients.
What are dopamine agonists?
Drugs such a L-Dope, cocaine, amphetamine and methylphenidate act as ‘dopamine agonists’- mimicking the effects of dopamine because of their similar molecular shapes.
What evidence did Davis find for the biochemical explanation?
Injected schizophrenics with methylphenidate (which increases dopamine) and found a marked increase in symptoms.
What is the issue with the biochemical approach?
-Ethical issues- Increases in dopamine leads to increases in positive symptoms, but not negative symptoms. Negative symptoms are better explained by structural brain abnormalities.
How else could dopamine contribute to SZ?
It might not just be about having too much dopamine. Schizophrenics are thought to have an abnormally high number of D2 receptors on their receiving neurons, resulting in more dopamine binding and therefore more neurons firing.
What did Torrey find about brain structure and SZ?
Using PET, MRI and Cat scans researchers have discovered that many schizophrenics have enlarged ventricles, cavities in the brain that supply nutrients and remove waste. The ventricles of a person with schizophrenia are on average about 15% bigger than normal
What did Brown et al find about brain structure and SZ?
found decreased brain weight and enlarged ventricles, which are the cavities in the brain that hold cerebrospinal fluid
What did Flaum et al find about brain structure and SZ?
also found enlarged ventricles, along with smaller thalamic hippocampal and superior temporal volumes.
WHat did Buchsbaum find about brain structure and SZ?
found abnormalities in the frontal and pre-frontal cortex, the basil ganglia, the hippocampus and the amygdale.
How does research on brain structure support the belief that there are two types of SZ?
Structural abnormalities have been found more often in those with negative/chronic symptoms, rather than positive/acute symptoms, lending support to the belief that there are two types of schizophrenia: Type 1 (acute) and Type 2 (chronic).
What did Suddath et al find about brain structure and SZ?
1990)used MRI to obtain pictures of the brain structure of MZ twins in which one twin was schizophrenic. The schizophrenic twin generally had more enlarged ventricles and a reduced anterior hypothalamus. The differences were so large the schizophrenic twins could be easily identified from the brain images in 12 out of 15 pairs.
What is the strengths of biological brain structure explanation for SZ?
- High reliability; tested and retested, in highly controlled environments2. Wider academic credibility
What are the limitations of biological brain structure explanations for SZ?
- Enlarged ventricles could be the effect rather than the cause-if the reduction in brain volume is the cause of the schizophrenic symptoms then it cannot explain why after 30 years of the initial onset, 35% of the schizophrenics are classified as “much improved”.
What are the strengths of the biological approach?
-HUmane, poses no blame on the individual or their family- tends to provoke little fear or stigma-effective treatments- well established scientific treatments
What are the limitations of the biological approach?
-Reductionist-Animal Studies-Relies on self report-Treats symptoms, not causes
What did Beng-Choon Ho find about brain structure and SZ?
in a longitudinal correlational study of 211 schizophrenics found that antipsychotic drugs have measurable influence on brain tissue loss over time.
What did Lewis find about brain structure and SZ?
administered antipsychotic drugs to primates and found a brain volume loss of 10% . However this was a correlational study so it does not show cause and effect and this study was carried out on animals so we cannot extrapolate to humans without caution.
How do phenthiazines aid in the treatment of SZ?
They bind with the D2 receptors on the neurons and therefore prevent the excess dopamine binding and causing SZ symptoms.
How may the psychodynamic approach use childhood events to explain SZ?
If you have a cold and uncaring environment than the child may focus on themselves resulting in a weakened ego so they lose touch with reality and the selfish ID is left in charge of the personality.
How may the psychodynamic approach use the idea of regression and a poorly developed ego to explain SZ?
the ego may be overwhelmed by the demands from the Id or by feelings of guilt from the super ego & so the individual regresses to the safety and security of the oral stage. In the 1st stage the ego has not yet properly developed & the child can’t distinguish between itself & its fantasies & the external world.
How may the psychodynamic approach explain paranoia?
Paranoia may be a consequence of projection – If you have aggressive feelings you may not want to admit you’re like this so it gets pushed onto other people. So you’re worried that other people want to harm you rather than you yourself harming someone. Hence paranoia.
What did Fromm-Reichmann say about the psychodynamic approach and SZ?
Schizophrenogenic mothers are likely to develop SZ in a child. Interviewed patients with SZ about their childhoods. Many patients had mothers that were cold, manipulative, domineering and unable to show affection (the child is still expected to be emotional/affectionate). The families tend to have high levels of conflict between them/high levels of emotional tension and poor methods of conflict resolution.
What did Brown et al find about the psychodynamic approach and SZ?
found that SZ’s who return to families with high levels of expressed emotion are almost 6 times as likely to suffer a relapse as those who return to families with low levels of expressed emotion. This offers support for the idea of a Schizophrenogenic family.
What is the issue with the idea of a schizophrenogenic family?
-Data is retrospective-Research suggests that most people with SZ don’t come from this type of family- Some people with SZ will suffer a relapse even if they’ve been moved from their families-Blames parents for their children’s problems.
How does the cognitive explanation view SZ?
Distorted thought processes may be a cause of SZ. Cognitive explanations focus on the conscious thought processes rather than the unconscious. SZ is seen as a consequence of poor information processing e.g. A faulty attentional system.
How does Hemsley use the cognitive approach to explain SZ?
- Failure to activate schemas2.The relationship between stored schemas and incoming information breaks down- an individual can’t make sense of context, don’t know what to expect. 3. Inability to attend selectively results in sensory overload- All information is seen as equally important so now there’s too much to cope with4. Superficial information appears relevant- this could cause delusions of reference, paranoia etc.5. Internally generated thoughts are attributed to external forces- can’t distinguish between stored schemas and external reality. Hence hallucinations.
How does Frith use the cognitive explanation to explain SZ?
- A breakdown in ‘meta-representational ability’ – our ability to become aware of our own goals & intentions & the ability to understand the beliefs and intentions of others. 2. This can lead to delusions of control – SZ’s may not realise that their own actions are a result of their own intentions. This gives rise to the belief that they are under alien control and their thoughts are being implanted in their heads.3. It can cause delusions of reference – SZ’s can’t interpret other peoples social signals or understand their intentions. They can’t tell if someone is talking to them or not.4. It can cause hallucinations & paranoia – they can’t tell whether a sound that they hear is an attempt of communication or not. So non speech sounds may be communicated as an attempt of communication so you hear voices. When others say they can’t hear what you hear they believe it’s a lie and manipulation (hence paranoia).
What are the strengths of cognitive explanations?
-May help understand the origins of particular symptoms
What are the limitations of the Cognitive explanations?
- Don’t explain why the symptoms are there in the first place-Different SZ have different parts of the brain suggested and show different symtpoms-Ignores environmental factors.
What is the argument against the limitation that cognitive explanations don’t explain why the symptoms are there in the first place?
Hemsley suggested that the hippocampus may be at fault. Frith proposed a disconnection between the frontal and posterior areas of the brain. Thus, brain mechanisms have been suggested.
