File - the Durham School Psychology Department!

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PSYA4 REVISION
PSYCHOPATHOLOGY (Schizophrenia)
PSYCHOPATHOLOGY
(Schizophrenia)
• Clinical characteristics
of the chosen disorder
Psychopathology
-Schizophrenia
• Issues surrounding the classification and diagnosis of their
chosen disorder, including reliability and validity
Do not answer questions on
depression, phobic disorders,
OCD!!!
• Biological explanations of their chosen disorder, for
example, genetics, biochemistry
• Psychological explanations of their chosen disorder, for
example, behavioural, cognitive, psychodynamic and sociocultural
• Biological therapies for their chosen disorder, including
their evaluation in terms of appropriateness and
effectiveness
•Psychological therapies for their chosen disorder, for
example, behavioural, psychodynamic and cognitivebehavioural, including their evaluation in terms of
appropriateness and effectiveness
Outline the clinical Characteristics of SZ
• More than just ‘symptoms’
• Explain, don’t list…
POSITIVE
• Hallucinations
2 types?
NEGATIVE
• Poverty of Speech (alogia)
• Flat Affect
• Delusions
These are? Types?
• Social Withdrawal…
‘OTHER’ Symptoms
• Catatonia
Stupor, Waxy Flexibility,
Gegenhalten
• Inappropriate effect
This is?
Outline the clinical Characteristics of SZ
Other things you can mention
• Diagnostic criteria
– E.g. at least TWO characteristic symptoms present for a
significant period (1mth); Significant signs of disturbance
(social, occupational) for 6mths)
• Incidence rate
• Subtypes (be sure to say the characteristic symptoms
of the subtype/s)
• Prognosis (include prodromal and active phase)
• Could mention the ‘new’ DSM criteria…
Discuss issues with the reliability and validity of
the diagnosis and classification of SZ
• Basically, this is asking ‘what are the problems associated
with diagnosis and classification of SZ?’
• Must be prepared to talk about RELIABILITY and VALIDIDTY
of diagnosis
– RELIABILITY: do different clinicians give the same diagnosis; is a
sufferer diagnosed with the same disorder on different
occasions
– VALIDITY: Is the diagnosis accurate? i.e does the patient actually
have SZ? Have they been mis-diagnosed?
• Could mention the different types of reliability and validity
in the context of diagnosis
Discuss issues with the reliability and validity of
the diagnosis and classification of SZ
RELIABILITY
• Consistency of Diagnosis
• May be as low as 0.11
(Whalley)
• Could be due to a number of
reasons (make sure you
explain)
– Use of different diagnostic
procedures (ICDvsDSM) as
each have different diagnostic
criteria
– Differences in the training and
experiences of the clinician
could lead to inconsistent
diagnosis
Mr B. tip - Use Rosenhan’s study as a LINK
between reliability and validity issues…
VALIDITY
• Accuracy of Diagnosis
• Studies suggest validity of
diagnosis is low
• Could be due to a number of
reasons (make sure you
explain)
– Nature of SZ (e.g. absence of
pathognomic symptoms; no
objective observable
symptoms; co-morbidity issues;
natural variability of SZ across
time and sufferers
– Issues with the clinician (e.g.
training and experience [inc.
knowledge of culture bound
symptoms – give an e.g!]; fear
of labelling, discrimination and
a self fulfilling prophecy)
Discuss issues with the reliability and validity of
the diagnosis and classification of SZ
EVALUATION / COMMENTARY
• Key Study = ROSENHAN ‘on being sane in insane places’ – shows diagnosis
was reliable but not valid. (make sure you can describe this)
• But problems with this study include low temporal validity (child of it’s
time), sample issues – cannot say ALL institutions have the same issues
with diagnosis of SZ
• Other commentary points
– Even with the problems, any diagnosis is better than no diagnosis because
with diagnosis a patient wouldn’t receive treatment
– Highlighting the problems with diagnosis has led to a number of
improvements with the system
• New versions of DSM have a list of culture bound behaviors
• Clinician training has improved to increase awareness of biases, etc
• DSM V has got rid of subtypes as they believed this was causing problems due to
overlapping symptoms
• DSM and ICD have been brought more in line
• Increased use of standardised procedures (e.g. Present State Examination) should
increase reliability and validity of diagnosis
Discuss issues with the reliability and validity of the
diagnosis and classification of SZ (8+16)
In the context of diagnosis of SZ, reliability refers to…
(could bring in inter-rater and test-retest)
It is suggested that the reliability of diagnosis is low.
Whalley found…
This could be due to a number of reasons. For example
the fact that different clinicians use different diagnostic
tools…
Another reason for low reliability in the diagnosis of sz
is…
In evaluation, there is research which has investigated
the reliability and validity of SZ diagnosis. One piece of
research is Rosenhan’s ‘on being sane in insane places…
So Rosenhan shows that there are issues with the
validity of SZ diagnosis. In the context of
diagnosis, validity means…
One reason that diagnosis of SZ may lack validity
is…
Another reason to explain the low validity of SZ
diagnosis is…
In evaluation, identifying the issues with diagnosis
of SZ has resulted in a number of practical
applications which have improved modern
diagnosis of the disorder. This includes… (NB say
why it helps!)
In addition…
This study shows…
However, there are problems with this study…
Finally, there is also the argument that a flawed
diagnosis and classification system is better than
no system at all. This is because…
What is wrong with these answers?
(and can you spot any errors?)
One explanation is the Dopamine
hypothesis, which suggests increased
action at dopamine pathways causes
schizophrenia. High DA action may be
caused by a number of aspects, such as
over sensitive D1 receptors and poorly
functioning enzymes which break down
DA. DA is thought to play a primary role in
the processing of sensory information,
movement and motivation.
According to the cognitive theory,
schizophrenia may be caused by irrational
thoughts which lead to cognitive
distortions – literally abnormal processing
of sensory information. In more detail, this
abnormal processing may be a result of
damage to cognitive systems such as the
central monitoring system. This system is
responsible for labelling actions as ‘being
done by me’.
Psychodynamic theory offers an alternative psychological theory. Here, the root
cause is unconscious conflicts which arise as a result of trauma in adulthood.
This trauma may cause abnormal development of the tri-partite personality (ID,
EGO, SUPER EGO). For example, it may cause the EGO to perform maladaptive
use of defence mechanisms such as regression when a person is faced with
trauma. Here a person is psychologically ‘going back’ to an early stage in their
life.
What is wrong with these answers?
(and can you spot any errors?)
One explanation is the Dopamine hypothesis,
which suggests increased action at dopamine
pathways causes schizophrenia. High DA action
may be caused by a number of aspects, such as
over sensitive D2 receptors and poorly
functioning enzymes which break down DA. DA is
thought to play a primary role in the processing
of sensory information, movement and
motivation. For schizophrenia, the DA hypothesis
makes sense as it would explain the classic
symptoms where these aspects are abnormal,
such as social withdrawal (loss of motivation)
and catatonia (movement abnormalities)
According to the cognitive theory, schizophrenia
may be caused by irrational thoughts which lead to
cognitive distortions – literally abnormal processing
of sensory information. In more detail, this
abnormal processing may be a result of damage to
cognitive systems such as the central monitoring
system. This system is responsible for labelling
actions as ‘being done by me’. For schizophrenia,
this makes sense as many symptoms could be
explained by this. For example, auditory
hallucinations may be a person who doesn’t
recognise that their inner voice is their own and
instead attributes it to an external source (e.g. God)
Psychodynamic theory offers an alternative psychological theory. Here, the root cause is
unconscious conflicts which arise as a result of trauma in childhood. This trauma may cause
abnormal development of the tri-partite personality (ID, EGO, SUPER EGO). For example, it may
cause the EGO to perform maladaptive use of defence mechanisms such as regression when a
person is faced with trauma. Here a person is psychologically ‘going back’ to an early stage in
their life, prior to the trauma they experienced, as this makes them feel psychologically ‘safe’. For
schizophrenia, this makes sense as many symptoms can be classed as childlike, such as
neologisms (making up words) and even visual hallucinations which may be representative of
childhood imaginary friends (these may serve a further psychological purpose however …
Discuss Biological Explanations of SZ
• Need to know at least TWO for top mark bands
• Bio explanations include
–
–
–
–
Genetic abnormalities
Biochemical - Neurotransmitter imbalances
Neuroanatomical Abnormalities
Viral Hypothesis
• When evaluating, consider the general strengths and weaknesses of
the BIOLOGICAL APPROACH
• Where possible, link to specific symptoms!
EXAMINERS LIKE RESEARCH WHEN DISCUSSING EXPLANATIONS
Discuss Biological
Explanations of SZ
EVALUATION
• Evidence - E.g. Gottesman / other family
studies
–
•
GENETICS
• Sz is likely to have a genetic basis
because of the observations that
Sz is present in ALL CULTURES and
tends to run in FAMILIES
• Established through TWIN,
ADOPTION, FAMILY studies which
assess CONCORDANCE rates
• Top band detail - saying Sz is
‘genetic’ is too simplistic
• Chromosone ____ (Gurling)
• Specific Gene? _______
(Tonegawa)
Some animal research
–
•
•
•
•
•
•
Difficult to separate the effects of nature and
nurture (shared environment criticism);
problems with the operationalisation of SZ –
different studies use different criteria making
it difficult to compare results
Problems with research? Extrapolation
INCOMPLETE because...
PARSIMONIOUS but too Simplistic as it
doesn’t take into account psychological
factors such as… which research has
suggested may play a role in SZ
DIATHESIS – STRESS the most complete
explanation
SOCIALLY SENSITIVE (who does it blame?
Why is this a problem?)
NEGATIVE MORAL IMPLICATIONS – may
diffuse responsibility for the disorder away
from the sufferer which may have treatment
implications (i.e. they feel that because the
disorder is not ‘their’ fault, there is no point
in seeking treatment)
BUT there may be PRACTICAL
APPLICATIONS…
Discuss Biological
Explanations of SZ
BIOCHEMICAL
• the DOPAMINE HYP
• Simple...
• Initially thought to be the case
because we know DA controls
perception, motivation, attention and
control of motor movements
• So this explains symptoms including...
•
High DA could be caused by a
number of factors including…
•
Other observations which indicate
high DA causes Sz (e.g. drug use
which causes increased action at
serotonin sites is often accompanied
with SZ type symptoms, including
hallucinations, delusions).
EVALUATION
• Evidence and supporting observations /
methodological problems with these
• Post mortem studies and Animal studies
useful for easy commentary points...
•
•
•
•
•
CAUSE and EFFECT issues
But why do we think it high DA is a cause and
not an effect?
But the TREATMENT AETIOLOGICAL
FALLACY...
INCOMPLETE (can explain positive but not
negative symptoms)
However, negative symptoms may be a result
of positive symptoms (e.g. social withdrawal
may be caused by delusions)
•
•
Parsimonious but reductionist
Same as before. Include reference to the
idea that DA imbalance may itself be caused
by something else (genetics)
•
Deterministic
•
Major Practical application... (use research to
support. “this study shows that drugs are an
effective treatment for SZ. As they are based
in the dopamine hypothesis, this in turn
VALIDATES the dopamine hypothesis of SZ)
Discuss Biological Explanations of SZ
Third / Back-up Theory
NEUROANATOMICAL
• Enlarged Ventricles
• Indicates atrophy to certain
brain regions / areas
associated with cognitive and
behavioural functions; link to
symptoms
• Accidents, genetics, may cause
abnormalities
EVALUATION
• Objective methods used to
support this theory (brain
scans)
• General points too!
VIRAL HYPOTHESIS
• Sz caused by a virus which is
contracted during pregnancy
(third trimester?)
EVALUATION
• Difficult to verify
(retrospective?)
• Incomplete
• General points too…
Discuss Psychological Explanations of SZ
• As with biological explanations, you need to know TWO for the
top mark band
• Psych Explanations include
– Cognitive (damage to cognitive systems)
– Psychodynamic (early trauma, abnormal tri-partite personality,
family systems [e.g. double bind; schizophrenogenic mothers])
– Behavioural / Social
• As before, remember to evaluate the approach on which the
theory is based
• Where possible, link to specific symptoms
EXAMINERS LIKE RESEARCH WHEN DISCUSSING EXPLANATIONS
Discuss Psychological
Explanations of SZ
COGNITIVE
• Sz a result of irrational thoughts
/ errors in cognitive processing
EVALUATION
• Supporting evidence
–
–
E.g. Frith and Done experimental fluency
tasks – compared to a control, SZ produced
fewer self initiated behaviours, indicating
damage to the SAS
But serious methodological Issues with the
study (task lacked mundane realism so may
tell us little about SZ in real life; sample issues
•
UNSCIENTIFIC and UNFALSIFIABLE – based on
abstract concepts (CMS, SAS) which are
difficult to test empirically. Relies on
subjective opinion
•
Cause and effect issues
•
More complete and less reductionist
compared to bio theories as it can explain
positive AND negative symptoms
•
Recognises Nature (bio) influences (these
may be the root cause of cog deficits)
– Supervisory attentional system
•
• Responsible for...
• Damage would lead to…
•
Practical Applications – therapies can be
focused on specific cognitive systems
Successful Therapy (CBT) derived from this
approach validates the theory
– Delusions, hallucinations, etc
• These may be caused by
damage to cognitive processing
systems
• Metarepresentation system
(overall control) but includes...
– Central Monitoring System
• Responsible for...
• Damage would lead to...
Discuss Psychological
Explanations of SZ
PSYCHODYNAMIC
• Sz caused initially by NEGATIVE EARLY
EXPERIENCES (e.g. Early trauma, such as...)
• This leads to unconscious conflicts (ID, EGO,
Super EGO), specifically…
• EGO may shatter – ID becomes dominant;
results in primary narcissism (which is…);
this would cause symptoms including...
• To regain control, the EGO may overuse
defence mechanisms such as REGRESSION
(which is…) as an attempt to go back to a
time prior to the trauma. This can explain
symptoms such as…
•
•
•
•
Could also bring in the role of dysfunctional
families and explain HOW these contribute
to SZ
Schizophrenogenic mothers
(characteristics?)
Double Bind situations
High expressed emotions (relapse as
opposed to starting point)
EVALUATION
• EVIDENCE E.g. OLTMAN
–
–
•
Problems with evidence
Based on RETROSPECTIVE DATA, Subjective,
bias, sample issues blah blah blah
ABSTRACT AND UNFALSIFIABLE
–
Difficult to test using empirical methods.
Heavily reliant on subjective opinions (prone
to bias)
•
CAUSE AND EFFECT ISSUES? It may be that the
schizophrenics behaviour causes the family unit
to be dysfunctional (e.g. double bind situations)
•
INCOMPLETE and OVERLY DETERMINISTIC
•
TOO SIMPLISTIC
–
–
•
Emphasises Nurture over nature
diathesis stress a better approach? (N.B this
approach lends itself very nicely to diathesisstress)
NEGATIVE MORAL IMPLICATIONS BUT
DOES HAVE PRACTICAL APPLICATIONS
Discuss Psychological Explanations of SZ
BEHAVIOURAL
• Social learning
• SZ may observe and imitate
symptoms from, for e.g. family
members, especially if it is observed
being reinforced (vicarious
reinforcement). Can explain why the
disorder appears to run in families)
•
•
•
•
Operant Conditioning
Learn SZ symptoms are followed by
with positive reinforcement in the
form of attention, etc
Absence of learning of ‘normal’
behaviour
As SZ is a complex disorder, it is
unlikely that ALL symptoms are a
result of maladaptive learning (but
some symptoms may be caused by
other symptoms so learning may be
the cause of the key symptoms…)
SOCIO-CULTURAL
• SZ caused by stress and pressures of
living in an urban environment
• Causes client to socially withdraw /
escape into a psychological fantasy
world
•
•
BUT... Urban drift argument suggests
SZs move to urban areas to access
treatment so this explains the high
occurrences of Sz in urban locations
(cause and effect
Diathesis-Stress?
THERAPIES for Schizophrenia
• TWO biological therapies
– EARLY BIO TREATMENTS (ECT, Lobotomies)
– DRUGS (typical and atypical anti-psychotics)
• TWO psychological therapies
– CBT
– TOKEN ECONOMY
Must be able to evaluate in relation to
APPROPRIATENESS and EFFECTIVENESS so use
these terms!
Bio Therapies 1
EARLY BIO TREATMENTS
• Based on the assumptions that
abnormal neurological activity (e.g. in
the PFL) causes SZ
•
– Methodological issues including
OPERATIONALISATION of improvement
ECT
– Bilateral and Unilateral
– Short term muscle relaxant and
anaesthetic given to…
– Small shock (0.6amps) for 1-2 seconds
– Causes convulsions and Seizures
– Repeated 2-3 times a week for 4-6
weeks
– Thought to work because…
•
EVALUATION
• Evidence of effectiveness (Tooth and
Newton, Tharyan and Adams – ECT vs
Placebo)
LOBOTOMIES
– Sever the connections to the frontal
lobes
– Classic vs Trans-orbital procedure
•
ETHICAL issues may make the
therapies not appropriate
BIO Therapies 2
DRUGS
• Typical Anti-Psychotics
– Based on the dopamine
hypothesis which suggests…
– APs are DA agonists in that they
reduce the action at DA sites
– Typical
• Bind to DA receptors, increase
the production of enzymes
which break down DA to reduce
DA action
EVALUATION
• Lots of Evidence of effectiveness
– But there are problems with the
evidence (e.g. lack of a placebo control
does not allow us to rule out
psychological effects; sample issues e.g.
only one type of SZ investigated; poor
operationalisation of improvement.)
•
– Typical APs very good at treating
Positive but not negative symptoms; A
typical more effective for negative
•
APs only effective as a chemical
straightjacket. We know this because
– So a more complete therapy would
involves
•
ETHICAL issues
–
–
–
–
– A-TYPICAL Anti-psychotics
• Action in the NIGROSTRIATAL
DOPAMINE PATHWAY and
MESOLIMBIC DOPAMINE
PATHWAY (e.g. they affect other
NTs); ‘hit and run’ approach)
Not effective for all
•
Side effects? Dependence?
Revolving door problem?
Cost-benefit analysis is key
Atypical APs have fewer side effects so
are more appropriate
But APs have PRACTICAL
ADVANTAGES making them more
appropriate than other psychological
therapies…
Psych Therapies 1
EVALUATION
•
Evidence of effectiveness plus methodological commentary
–
•
CBT
• Based on the assumption
that irrational cognitions
lead to distortions in
information processing
which leads to SZ
symptoms
• THREE stages
Pilling; Tarrier (good use of a control);
More Effective in the long term (e.g. compared to drugs) because
they focus on the root cause of SZ (irrational thoughts) AND
teach practical strategies which can be used in the future
–
Most effective when used in combination with AP medication
(KOPELOWICZ)
•
Not effective and appropriate for all symptoms (serious delusions
/ extreme psychosis – a person will never accept their beliefs are
irrational)
•
Not effective/appropriate with young, low IQ, elderly, because
they will not understand the complex therapy
– Identification of irrational
beliefs
– Challenge and dispute
•
irrational beliefs (e.g.
through the use of
experiments)
– Replace and restructure
•
belief system and practise
real world application (may
involve the use of a diary)
•
Appropriateness questioned on ethical grounds - Confrontational
nature may cause anxiety
Ignores important causal factors (biological) so may not be
appropriate unless combined with AP
Practical advantages compared to other psych therapies (limited
to a small number of sessions over a few weeks) but has
disadvantages compared to drugs (CBT needs a well trained
therapist to deliver, etc)
EVALUATION
Psych Therapies 2
•
–
TOKEN ECONOMY
• Based on the behavioural
•
theories which suggests SZ is
nothing more than a set of
abnormal learned behaviours
so therefore these can be
replaced with learnt ‘normal’
behaviours
•
• OPERANT CONDITIONING is key
– Token given for normal
behaviour (positive
reinforcement)
– Token is secondary reinforcer •
because…
– Tokens exchanged for primary
reinforcers suchs as…
– Punishment may occur when a
client shows SZ symptoms
(token taken away)
•
MAKE SURE YOU APPLY!
Evidence of effectiveness and methodological issues
•
Ayllon and Azrin (only used female SZs so...); Paul and Lentz
(operationalisation of improvement)
Not effective in the long term as symptoms return
outside of the structured institute where the TE was
taking place – suggests TE does not treat the root cause
and that clients ‘fake’ improvement to achieve tokens
Appropriateness questioned on ethical grounds because
TE may involve clients being denied basic human rights
until they achieve tokens (food, etc)
Not appropriate due to PRACTICAL DISADVANTAGES as it
requires trained professionals to administer a TE
programme and constant monitoring
–
BUT improvements are quick so it is an appropriate way to
quickly control symptoms within institutions
Alternative treatments more successful and more
appropriate…
–
Use evidence to support this point (e.g. APs effective in 85%
of cases; LIBERMAN compared CBT and TE and found CBT
was more effective in long term)
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