schizophrenia wb
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Psychopathology
(Abnormality)
PSYA4Unit 4
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Issue with classification and diagnosis
Key word Definition
Classification
Diagnosis
Task: What diagnostic tools are used to diagnose psychological disorders?
1.
2.
Problems with classification and diagnosis
Task: Match the criticism with the correct response
Criticism Response
Extension:
How can the problems of classification and diagnosis be overcome?
You cannot treat mental illness the sameway as a physical illness
Thomas Szasz (1962) The myth of mental
illness- classifications encourage treating
problems of living as an illness. It
removes responsibility from the
individual for solving their own problems
Diagnosis someone can lead to stigmas.
An individual with a mental illness may
be wrongly judged. Labelling sociallydeviant behaviour as a mental illness
causes more problems for that person
Some individuals do not fit neatly into
diagnostic categories
Mental illness should not solely onlybe diagnosed by socially deviant
behaviour but by the presence of a
range of symptoms
Although few individuals do not fit
into the existing categories this is not
a reason to abandon classification
systems
There is evidence for the existence of
certain distinct syndromes which are
bought about by factors other thanstressful living
It is not the diagnostic labels which
lead to stigmas. People were
stigmatised before diagnostic
categories
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Diagnosing schizophrenia
1. What is schizophrenia (SZ)?
2. Facts about SZSchizophrenia is the most common and well known psychotic disorder, in most countries of
the world it occurs in around 1% of the population over 18.
Task: watch the video clip and make a list of facts about SZ
3. According to DSM-IV the criteria for SZ include:
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4. Identify at least 3 positive and 3 negative symptoms of SZPositive Negative
Extension:
How many positive and negative symptoms are identified within the DSM-IV?
Which are easier to treat with drugs- positive or negative symptoms?
5. Onset of SzAcute Chronic
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So if a person presents with any combination of the above signs and symptoms a clinician
would diagnose them with SZ, right? Well in fact it is not that simple! The reason for this
is that there are five sub-types of SZ, each with varying characteristics.
Sub type of SZ Characteristics
Paranoid
Catatonic
Hebephrenic
disorganised)
Undifferentiated
Residual
Extension:
Read the case study- can you diagnose WG?
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Issues surrounding the classification and diagnosis of Schizophrenia
Reliability of diagnosis
There is no official diagnostic test for schizophrenia. However, to try and help diagnose
schizophrenia more accurately clinicians often use other diagnostic tools that have been developed.Other tools include the Schneider Criteria, Research Diagnostic Criteria, St Louis Criteria etc.all of
these are still used by clinicians.
Farmer et al (1988)found high levels of reliability using the standard interview technique known as
PSE (Present State Examination).
People diagnosed with schizophrenia often have very different symptoms, the course of the illness is
different, their response to treatment is different and the causal factors are different.
There are two classification systems used for schizophrenias including DSM-IV- TR and ICD-10.
Initially the two classification systems were very different. Prior to the 1970s there was a significantdifference in the prevalence rates of schizophrenia in different countries. In America, the rate of
people diagnosed with schizophrenia was quite high compared with other countriesit has been
suggested that this is because their classification systems were much broader.
In the US 20% of patients were diagnosed with schizophrenia in the 1930s, but in1950s this went up to 80%.
Whereas in London at the Maudsley Hospital in London, the diagnosis rate of 20%remained constant over that period (Cooper et al 1972).
To try and fix these differences the two classification systems (DSM-IV and ICD-10) were made more
similar.
This has led people to suggest that schizophrenia is not a single disorder and various sub-types have
been suggested. However, the validity of these sub-types has been questioned.
Sub-types of schizophrenia:
1. Paranoiddelusions and hallucinations. Do not usually have absence of feelings andemotions of disorganised speech.
2. Catatonicunusual motor activity (either agitation or immobility), often extreme negativismand strange posturingvery rare disorder.
3. Hebephrenic (ICD) or Disorganised (DSM)often begins early age, incoherent anddisorganised speech, lack of feelings or emotions (known as flat affect). Sometimes
hallucinations and delusions.
4. Undifferentiateddiagnosed when showing clear schizophrenic symptoms that do notfit into the other categories.
5. Residualat least one episode of schizophrenia but no longer showing obvious signs of thedisorder.
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1. What is the diagnostic test for schizophrenia?
2. What is reliability?
3. Is the diagnostic test for SZ reliable? Fill in the tablePoint Example Explanation
Twodiagnosticmanuals
Inter-reliability?
Different
ypes ofSZ
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Issues surrounding the classification and diagnosis of Schizophrenia validity of diagnosis
Key term Definition
Validity
Co-morbidity
1. Rosenhan (1973) - On being sane in insane places
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Issues surrounding the classification and diagnosis of Schizophrenia validity of diagnosis
Factor to
consider
Explanation Example
Does Sz really
exist?
Cultural variation
Dual diagnosis
Language
difficulties
Co morbidity
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Biological explanation of Schizophrenia - Genetics
Learning objectives:
To be able to explain the extent to which Sz could be genetic To discuss research into twin and adoption studies To evaluate research into the genetic basis of Sz
There are various ways to decide whether or not genetic factors are important in SZ. What
studies are used to investigate genetic link.
1.
2.
3.
The Genetic Hypothesis
1. Twin studiesMuch of the evidence concerning the involvement of genetic factors in SZ comes from the
study of twins. Researchers want to establish the probability that the other twin is also SZ-
this is known as concordance.
There are two types of twins, and they are different from one another in two ways:
MZ (___________________________) twins: only egg is fertilised buttwo foetuses
develop, so they share % of their DNA.
DZ (_____________________) twins: . eggs are fertilised at the same time, so they
share. % of their DNA, and are no more related than normal siblings. They are
sometimes called twins.
Rosenthal (1963) -(the Genain quadruplets) studied quadruplets in which all four girls were
identical to each other. All four of them developed SZ, although they did differ in age of
onset and the precise symptoms. It is worth noting that they had a dreadful and aberrant
childhood, so the conclusion of this investigation is not clear-cut.
Gottesman (1991):
Cardno et al (1999)
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Issues with twin studies
Point Example Explanation
Rarity of twins
Concordance rate
Problems with
diagnosis-
different
diagnostic
criteria
2. Family studiesGottesman et al (1991)found that the likelihood of an individual developing Sz is
proportional to the amount of genes they share (If a member of your family has Sz then the
closer you are to them genetically, the more likely you are to develop Sz)
The findings from this study were as follows:
MZ twins - ____ Children of two affected parents - ___ DZ twins - ____ Grandchildren - ____ The general population - ___
Kendler et al (1985)
Issues with family studies
Point Example Explanation
Nature-nurture
debate
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3. Adoption studiesThese allow us to study individuals born to a Sz sufferer but raised by parents with no
history of SZ; this allows us to investigate the nature-nurture debate; separating out the
effects of environmental and genetic factors.
Kety (1994):
Tienari (1991):
Evaluation- The Genetic Hypothesis
+/-/
DA
Point Example Explanation
Reductionist
Nature-
nurture
debate
Diathesis-
stress model
VULNERABILITY +
STRESS = DISORDER
It is now thought that our genes and our environments interact in some way.
DIATHESIS means susceptibility to illness. STRESS is the psychological reaction to
meaningful events. The more susceptible you are, the less triggers you need
Deterministic
Psychology is
a science
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Biological explanation of Schizophrenia - Neurotransmitters
Learning objectives:
To be able to explain the dopamine hypothesis of Sz To discuss research and evidence to support the dopamine hypothesis To be able to evaluate the dopamine hypothesis
The dopamine hypothesis
Genetic factors may lead to differences in brain chemistry, so that it is the brain chemistry
that is the immediate casual factor. Biochemical abnormalities may be important in the
development and maintenance of SZ. Some psychologists suggest that the neurotransmitter
dopamine is involved in causing schizophrenia. It first began following the discovery that
schizophrenic post-mortems revealed a high level of the neurotransmitter. Therefore, it
was first believed that schizophrenia resulted from an excess of dopamine (Seidman 1983).
A slightly different view is that neurons in the brain of SZ patients are oversensitive to
dopamine.
What three pieces of evidence exist, that link schizophrenia with dopamine?
Hint: what drugs are used to treat SZ?
Drug How it works/ its link with SZ
Chlorpromazine Blocks dopamine receptors
Post-mortem
and PET Scan
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Despite this amount of support, the dopamine hypothesis is not without its limitations:
+/-
/IDA
Point Example Explanation
Individual
differences
L-dopa and amphetamines do not worsen symptoms in all
people suffering from schizophrenia
The difficulty
with post-
mortems
Variable
results in
research
PET scans carried out
more recently (Farde et
al, 1990) have not
replicated Wongs
findings.
This means that
Cause and
effect
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Biological explanation threeNeuroanatomical factors
Learning objectives:
To be able to explain how Sz could be the result of brain abnormalities To evaluate the influence of neuroanatomical factors on Sz
There is an increasing amount of evidence to suggest that people with schizophrenia may
have abnormalities in the structure of their brains. Stevens (1982) cites the fact that many
schizophrenics display symptoms indicating neurological disease - especially decreased eye
blinking, lack of the blink reflex, poor visual pursuits and poor pupil reactions to light. Some
schizophrenics underwent prenatal complications and may have suffered a lack of oxygen
resulting in possible brain damage.
Frontal lobe abnormalities
This area is responsible for higher intellectual functioning and fluent language, and the
frontal lobes of schizophrenics have been found to be smaller than non-schizophrenics.
Buchsbaum (1990)
Ventricle abnormalities
The ventricles in the brain are fluidfilled cavities, which appear to be larger in people with
schizophrenia (particularly the left ventricles).
Brown et al (1986)
Flaum et al (1995)
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Extension:
Neurodevelopmental hypothesis
Brain lesions occurring very early in development (possibly) before birth can make
individuals affected vulnerable to SZ.
Wright et al (1999) - reported data from several countries on the incidence of SZ in children
born to mothers who had flu during pregnancy. There was an elevated risk of SZ in these
children especially when mothers had flu between the fourth and seventh month of the
pregnancy.
Dalman et al (1999)
Van Os and Selten (1998)
Point Example Explanation
Cause and
effect
Conflicting
indings
Different areas in the brain
associated with SZ
Other
actors?
Brain abnormalities are not
present in all people with
Sz, therefore it has been
suggested that there are
two types of Sz; each having
a different underlying
pathology
Type 1
Type 2
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Biological Treatments for SZ
Biological psychologists have claimed that mental illness resembles physical illness and the
cause of mental illness resembles those of physical illness. Mental illness is depends on
some underlying organic problem and the best form of treatment involves direct
manipulation of the physiological system within the body. For these reasons the mostcommon biological treatment is drug therapy.
Neuroleptic/ antipsychotic drugs (drugs that reduce psychotic symptoms but can also
produce some of the symptoms of neurological diseases) are often used in the treatment of
schizophrenia.
Drug How does it work?
Phenothiazine/
Chlorpromazine
(conventional
drugs- first
generation)
Note: only worked for 75% of patients- additional reading below
Clozapine
(Atypical anti-
psychotic drugs-
second
generation)
Note: more effective than conventional drugs in treating the negative symptoms of SZ as well
as positive symptoms. More successful in treating the 25% of patients who were not helped by
first generation of drugs.
Windgassen (1992) found that:
about half of SZ patients taking neuroleptics (conventional drugs) reportedgrogginess or sedation;
18 % reported problems with concentration; 16% had problems with salivation; 16% had blurred vision 20% who had taken the drug for over a year develop the symptoms of tardive
dyskinesia- these symptoms include involuntary sucking and chewing, jerky
movements of the limbs and writhing movements of the mouth or face and the
effects can be permanent.
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Evaluation of drug therapy
Point Example Explanation
Treating the
symptoms notthe cause
Side effects
Cost
Responsibility
taken away
from patient
and give it
directly to the
therapist or
psychiatrist
Patients
compliance
with
treatment
Some patients
do not
respond to
drug
treatment.
About 30-40% of patients
treated with drug therapy
do not respond to
treatment.
Individual differences are ignored. This figure questions the usefulness
and effectives of drug therapy for treating SZ.
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Additional reading:
As far back as the Middle Ages, those suffering from mental illness had holes cut in their
skulls to allow the devils to allegedly causing the illness to escape. This practice was known
as trepanning. It did not produce any cures and many of those who were subjected to thisprocedure did not survive the operation.
Psychosurgery is the use of brain surgery to reduce psychological or behavioural disorders. In
the 1930s Moniz used the surgical method of prefrontal lobotomy, in which fibres running
from the frontal lobe to other parts of the brain were cut. Moniz and others claimed that this
procedure made SZ patients less violent and agitated and much easier to manage. About
70,000 lobotomies were carried out between 1935 and 1955. The side effects of this
operation were so severe that this procedure is rarely performed anymore. These side effects
include apathy, diminished intellectual powers, impaired judgement, comas and death.
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Psychological explanations of schizophrenia- Psychodynamic Theory
Learning objectives:
To be able to outline the psychodynamic explanation of SZ To discuss research and evidence to support the psychodynamic explanation of SZ To be able to evaluate the psychodynamic explanation of SZ
Sigmund Freuds psychodynamic theory was primarily developed to deal with anxiety and
neuroses. Freuds original ideas focusedupon psychosexual developments and how children
came to terms with their sexuality. This original emphasis makes it hard to apply this
approach to SZ. Although Freud is not the only psychodynamic therapist he is the most
influential, and such therapist, even if they play down the psychosexual element of the
theory, still focus on childhood problems as a start of a process that will result in SZ.
The Schizophrenic Family
The basic psychodynamic assumption for the development of schizophrenia stems from
some type of disruption to early family relationships.
Klein (1946) and Bion (1967) proposed that all children go through stages of development in
which they are dominated by feelings of persecution and omnipotence. A poor relationship
with the primary carer can prevent a child outgrowing these beliefs, resulting in the child
becoming vulnerable to developing schizophrenia later in life.
If a child develops a schizophrenic core of personality due to poor early relationships, then
as an adult, they may regress to these characteristicsclassic symptoms of schizophrenia.
1. What symptoms could be considered examples of regression?
Some theorist have argues that there are abnormal and inadequate patterns of
communication within families of SZ patients.
2. The characteristics of a SZ family include
3. Bateson et al (1956) double bind hypothesis states that
4. According to Lidz (1973), schizophrenics' families are frequently marked by maritalschism or marital skew.
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Marital schism.
Expressed Emotion
There is evidence that the interactions within families can play a key role in maintaining the
symptoms of individuals already suffering from SZ. What seems to be important is the
extent to which a family engages in expressed emotion, which involves criticism, hostility
and emotional overinvolvment. Individuals who have suffered from SZ and who live in
families with high expressed emotion are nearly four times as likely to relapse compared
with those who live in families with low expressed emotion (Kavangh 1992).
When those with SZ improve enough to return home from a period of hospitalisation, their
family might treat them differently from how they treated them before. This can be in the
form of being excessively concerned as well as showing negative emotions such as hostility
or resentment.
The direction of causality is not clear in studies of expressed emotion is not clear in studiesof expressed emotion. One possibility is that expressed emotion within the family causes
relapse. Another possibility is that individuals who are in poor psychological shape are more
likely to provoke expressed emotion from members of their family.
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Evaluation of Psychodynamic explanation for SZ
Point Example Explanation
Does not
explain the
variety of
symptoms
caused by SZ
Blames the
family-
deterministic
Its approach to
childhood
developmental
problems it
too simplistic
Causality
Difficulty to
falsify
The approach cannot be
falsified because it is based
on the assumption that
unconscious forces play a role
in disorders
Unconscious forces/desires cannot...
Little evidence
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Psychological explanations of schizophrenia - Cognitive
Cognitive theorists assume that these cognitive deficits are linked to underlying
physiological abnormalities; meaning that neurological and cognitive ideas are combined in
what is referred to as a neuropsychological model.
The cognitive model views thought disturbances as causes rather than consequences, and
Maher (1968) sees the use of bizarre language as a result of faulty information processing.
Two of the most famous neuropsychological theories are by Frith (1992) and Helmsley
(1993).
Firth- failure to understand context
Firth (1993) talks of SZ as a failure to appreciate the context of a situation. This, for example
would make it difficult to work out the beliefs and intentions of those around you. If, forexample, someone stood to offer you a seat on the bus, you might think they had done so
because you were carrying a lot of shopping. Someone with SZ on the other hand, might
interpret the gesture with suspicion or even with paranoia.
Firth believes that this behaviour is caused by under activity of the frontal lobes of the brain,
which handle motivation and action. This is underpinned by an irregularity of the neural
pathways connecting the hippocampus to the pre-frontal cortex (linked to dopamine
regulation in this part of the brain).
Frith proposes that Sz suffers are not able to distinguish between actions influenced byexternal forces and those driven by internal intentions.
Frith (1992) also argued that positive symptoms of SZ may occur because SZ have problems
with self-monitoring. What happens is that patients fail to keep track of their own
intentions, as a consequence of which they mistakenly experience their own thoughts as
alien.
Hemsley- failure to utilize schemas
Helmsley believes that some of the symptoms of Sz arise from a disconnection between
stored knowledge and current sensory input. Our stored knowledge is referred to as ourschemas. He suggested schizophrenics cannot distinguish between information that is
already stored and new incoming information. As a result, schizophrenics are subjected to
sensory overload and do not know which aspects of a situation to attend to and which to
ignore.
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Evaluation of Cognitive explanation for SZ
Point Example Explanation
Limited but
valuable
Causality
Genetic
origin of
cognitive
impairments
Differences
between
Firth and
Hemsleys
theories
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Evaluation of the Behavioural explanation for SZ
Point Example Explanation
Are all the
behaviours
common to
SZ learnt?
Positive symptoms:
Causality
Limited
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