Schizophrenia – Highly Detailed – Extension

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Schizophrenia
Symptoms, Types Causes,
Treatment, Case Studies for
Evaluation
Schizophrenia: Definition
• The most debilitating psychosis and the closest to the
layman’s definition of madness.
• Kraepelin (1896) called it dementia praecox (senility of
youth) because the symptoms occur fairly early on in life
and result in a gradual deterioration.
• Bleuler (1911) suggested that symptoms can occur later,
and coined the term schizophrenia, (‘split mind’ in Greek)
which symbolises the fragmentation of the sufferer's
personality.
• Schizophrenia exists world-wide, but its symptoms can
vary from culture to culture.
• Schizophrenia comprises a number of symptoms which
in different combinations produce three different types of
the disorder.
Symptoms of Schizophrenia
First Rank Symptoms
• In Britain, schizophrenia is only diagnosed in the presence of one of the following ‘first
rank’ symptoms (disturbances of subjective experience as reported verbally by the
individual).
1) Disturbance of thought: the belief that thoughts are being inserted into the
individual’s mind from outside (thought insertion) or removed from their mind by
external forces (thought withdrawal), or that their thoughts are being made known to
others (thought broadcasting).
2) Hallucinations (the experience of sensory stimuli which are not present)
• Auditory (the most common). ‘Voices’: offer a commentary on the individual's
behaviour "he is eating his dinner";
• make disparaging remarks about him "he eats like a pig ";give him commands "put
the knife on the plate".
• ‘Voices’ may be a distortion of environmental noises (fridge or radiator noises
interpreted as whispering) or projections of the individual's own thoughts (thoughts
may enter the individual’s internal speech loop or even become spoken aloud without
the individual realising that the thoughts / speech are his own (malfunction of the
feedback loop).
• Somatic e.g. experience of electric shocks to the fingertips.
Symptoms of Schizophrenia
(contd)
3)
•
Delusions (beliefs which individuals are firmly convinced are true,
regardless of evidence to the contrary). These can come in:-
Delusions of grandeur: the individual is someone important or
powerful (Christ, Napoleon).
• Delusions of persecution: the individual is being conspired
against/interfered with by other people or organisations (M15, the
Mafia).
• Delusions of reference: the individual believes that unrelated events
have personal significance e.g. the words of a song refer to them
personally.
• Other common delusions: the belief that nothing really exists and all
things are simply shadows; the belief that one has been dead for
years and it is observing the world from afar.
Other Symptoms
These are symptoms not classified as ‘First Rank’ but are reported by observer’s of
patients’ behaviour:Thought Process Disorder
• a) Loose Association: the individual is unable to focus attention so he/she moves
from one topic of thought to another in a disjointed, illogical way.
• b) Word Salad: disjointed thought leads to incoherent, rambling language association
e.g. ‘I am the King of Spain, the daughter and the fruit tree, blossom in Spring’.
• c) Clang association: the sound of one word triggers association with another word
e.g. ‘The King of Spain feels no pain in the drain of the crane’.
• d) Invention of new words and combining existing words in unusual ways e.g. ‘ belly
bad luck and brutal and outrageous’ to describe stomach ache.
• e) Echolalia i.e. repetitive echoing of words spoken by others.
Motor Symptoms
• a) Catatonia: the individual stays mute and motionless in a fixed position for hours or
days on end.
• b) Stereotypes: the individual moves repetitively e.g. rocks to and fro.
• c) Agitation: including sudden, disturbing, unpredictable gestures and grimaces for no
apparent reason.
Other Symptom (contd)
Emotional Disturbance
• a) Blunting: apparent indifference to events which would normally
provoke a strong emotional reaction.
• b) Inappropriate Affect: e.g. laughing when told bad news, reacting
angrily if offered a gift.
• c) Flattened Affect: absence of emotional expression, speech is in
monotone, no mobility of facial features, vacant gaze.
Lack of Volition
• Loss of interest in the external and social world. Loss of drive.
• Inability to act, including inability to perform everyday living activities
e.g. washing, cooking.
Disordered Sense of Self
• Sufferer has little idea who he / she is and has no ego-boundaries.
The sufferer displays autism, and lives in a fantasy world, taking no
notice of the world around them.
Types of Schizophrenia
• Previously schizophrenia was classified into two types:
Acute (TYPE 1)
also known as positive syndrome schizophrenia.
sudden onset, with delusions and hallucinations as
early symptoms.
Chronic (TYPE 11)
also known as negative syndrome schizophrenia.
insidious onset with a history of apathy and social
withdrawal (loners)
worse prognosis than for acute schizophrenia.
Types of Schizophrenia (contd)
Now schizophrenia is classified into four main types:
Disorganised Schizophrenia: (the most severe type) onset:
adolescence or early adulthood; Disorganised thought and language
(loose association and word salad); Disorganised delusions and
vivid hallucinations, inappropriate and flattened affect; Disorganised
behaviour and extreme social withdrawal
Catatonic Schizophrenia Catatonia or agitation; loss of drive;
echolalia (involuntary repetition of sounds uttered by others)
Paranoid Schizophrenia onset: later than other types; Well organised
delusions and hallucinations; Language, behaviour and the ability to
carry out daily functions remain relatively normal.
Paranoid schizophrenics show the highest level of awareness!
Undifferentiated Schizophrenia is a diagnosis for people with mixed
symptoms who don’t fit any of the types clearly. Other related
disorders include:
a) Brief psychotic disorder b) Substance Induced psychotic disorder
Evaluating the Types of
Schizophrenia
• Although these types form the basis of current diagnostic systems,
their usefulness is often questioned. Because diagnosing types of
schizophrenia is extremely difficult, diagnostic reliability is
dramatically reduced.
• Furthermore, these sub-types have little predictive validity; that is,
the diagnosis of one over another form of schizophrenia provides
little information that is helpful in either treating or in predicting the
course of the problems.
• There is also considerable overlap among the types. For example,
patients with all forms of Schizophrenia may have delusions.
Kraepelin’s system of sub-typing has not proved to be a useful way
of dealing with the variability in schizophrenic behaviours.
Evaluating the Types of
Schizophrenia (contd)
• A system that is currently attracting much attention distinguishes
between positive and negative symptoms (as opposed to types of
patients) continues to be used increasingly in research on the
aetiology of schizophrenia.
• Aetiology is defined as the science that deals with the causes or
origin of disease, the factors which produce or predispose toward a
certain disease or disorder. It is a medical term.
• Andreasen and Olsen (1982) evaluated fifty-two patients with
schizophrenia and found that sixteen could be regarded as having
predominantly negative symptoms, eighteen as having
predominantly positive symptoms, and eighteen as having mixed
symptoms.
• Although these data suggest that it is possible to talk about types of
schizophrenia, subsequent research has indicate that most patients
with schizophrenia show mixed symptoms (e.g. Andreasen, Flaum
et al.,1990) and that very few patients fit into the pure positive or
pure negative types.
The Course of Schizophrenia
Patients with Schizophrenia have been seen to go through three
phases/stages:1. Pro-modal phase: Characterised by a steady deterioration including
emotional flatness and loss of drive. In Type 1, this is short, in Type 11 the
onset is insidious (harmful).
2. Active Phase: involves major symptoms
3. Residual Phase: when the sufferer is in remission (return to the pro-modal
phase).
Note:• The three stages are not always clearly separable and the duration of each
phase is variable.
• A third of sufferers have one or two acute episodes (active phase) and then
return to normal.
• A third have periods of acute episodes and remissions (residual phase)
• A third deteriorate progressively (from active to chronic symptoms) over
time
Evaluating Schizophrenia:
Focusing on Case Studies
DNA Markers
Family history research
You need to be able to describe and
evaluate TWO pieces of research in
each of the following areas
Twin studies
Adoption studies
BRAIN ABNORMALITY
GENETICS
Biochemical imbalance
Brain damage
BIOGENIC EXPLANATIONS FOR
SCHIZOPHRENIA
Birth complications
Viral theory
Study number one
Family
History
Studies
The Copenhagen High-Risk study
(Kety et al 1962,1974,1989).
This meant a 35% risk of
developing schizophrenia in
the high risk group versus a
7% risk for controls.
Procedure identified 207 children
with a schizophrenic mother (high
risk group) and 104 with a nonschizophrenic mother (controls).
Found that at age 42, a total of 67 of
the high risk group had been
diagnosed as having either
schizophrenia or schizotypal
personality disorder versus 7 in the
low risk group
Study number two
Family
History
Studies
Zimbardo (1995)
The degree of risk of
developing schizophrenia
also correlates highly with
the degree of genetic
relatedness to a family
member who has suffered
from the disease.
Among the general population the risk
of developing schizophrenia is 1%. He
found for a brother or sister of a
schizophrenic it is 9%, for a child with
one schizophrenic parent 13%,
for a child with two schizophrenic
parents 46%.
He compiled a risk table from
studies of European populations
between 1920 and 1987.
Twin
Studies
Cardno (1999)
Evaluation
ca n 't s e p a ra t e n a t u re &
n u rt u re , e xp e ct M Z
to ge the r to be highe s t
ra t e . B u t n o t 1 0 0 % .
St re s s vu l n e ra b i l i t y m o d e l
ca n e xp l a i n t re n d s a s M Z
t w i n s d o n 't h a ve M Z l i ve s
Concordance study
of DZ & MZ twins
reared together
Study number three
5.3% DZ concordance
40% MZ concordance
Suggest some commentary
Study number four
d iffe re n t ia t e b e t w e e n n a t u re & n u rt u re
(re a re d a p a rt ), s a m p le s iz e la cks
g e n e ra lis a b ilit y,b u t it is p a rt ly g e n e t ic
Gottesman and
Shields (1982)
Concordance study on a dozen
pairs of MZ twins, reared apart
58% concordance rate
Study number five
Is this evidence any more
Procedure identified 50 children
reliable? If so why?
with a schizophrenic parent (high
co n co rd a n ce ra t e s q u it e h ig h , b u t
risk group) and 50 children with
p ro p o rt io n a l ch a n ce re m a in s t h e s a m e
non schizophrenic parents
a s t h e fa m ily h is t o ry s t u d y (5 x m o re
like ly in H ig h R is k g ro u p )
(controls). Half from each group
s a m p le a t t rit io n in lo n g it u d in a l re s e a rch
d ia g n o s t ic crit e ria ch a n g e
were brought up in a kibbutz
s o m e s u p p o rt fo r t h e ro le o f n u rt u re a s a
(communally, separate from their
ca u s e b u t n o t t h a t m u ch
s a m p le s iz e is s u e s
parents) the other half in
cu lt u ra l s o cia l fa ct o rs in fla t in g ra t e s
families
Israeli High Risk study
(Marcus 1967 and 1987)
At a 13 year follow-up 22 of the high risk group
had been diagnosed with schizophrenia but
only 4 of the control group (16 were kibbutz
raised, 10 from traditional families).
Adoption studies
Adoption studies
Can you see a pattern
emerging from all these
findings?
lo ngitudina l is s ue s
s i m i l a r ra t i o (5 x)
ra t e s a re m u ch l o w e r a n d C L O SE R
t o e xp e ct e d l e ve l s
d i a g n o s t i c cri t e ri a m a y ch a n g e fro m
o n e p l a ce t o a n o t h e r
co m p a ri n g T i e n a ri & M a rcu s
s u g g e s t s a ro l e fo r cu l t u ra l fa ct o rs ,
5 x ra t i o i s re l i a b l e p a t t e rn
Procedure identified two groups of
adopted children. 112 adoptees
with a schizophrenic biological
parent (high risk group) and 135
adoptees without a schizophrenic
parent (controls).
The Finnish Adoption Study
(Tienari, 1969 and 1987)
At an 18 year follow-up, 7% of
the high risk group had been
diagnosed as schizophrenic
and only 1.5% of the controls.
Study number six
Debate!!!
Schizophrenia is inherited
Summarise the evidence of the case for a
genetic cause
Summarise some of the problems with this
evidence
Why?
Are there other possible causes?
Cause One:Brain
Biochemistry
The Dopamine Hypothesis
The hypothesis suggests a positive correlation between high levels of
dopamine in the brain and Acute symptoms of schizophrenia.
Drug
Effect on Dopamine
Levels
Symptoms in the
Individual
Phenothiazine
(anti-psychotics)
Reduces disordered
thoughts and behaviour
symptomatic of Acute
schizophrenia.
Side-effect: Parkinsonlike stiffness and
tremors.
Cocaine and
Amphetamines
Can cause paranoia and
hallucinations.
Exacerbates
schizophrenic symptoms
in sufferers (Davis 1974)
L-dopa
Reduces Parkinson’s
stiffness and tremors.
Side-effect: Can produce
Acute schizophrenic
symptoms.
Iverson (1979) thought schizophrenics suffered from excessive dopamine production, as he found high
levels of dopamine in the brains of schizophrenics at post-mortem.
But Davis et al (1991) showed that schizophrenics have 6 times more dopamine receptor sites and / or
more sensitive post-synaptic receptors causing more dopamine to be utilised.
relies on drug effects for evidence.
Discussion
• Acute symptoms respond well to dopamine treatment but Chronic
symptoms don’t.
What are the implications of this finding?
• Does increased dopamine production cause schizophrenia or does
schizophrenia cause increased dopamine production?
What kind of relationship has been shown?
• Dopamine is also implicated in psychiatric disorders other than
schizophrenia.
Is it the cause or merely a factor?
• Women are less susceptible to schizophrenia than men and more
likely to suffer late onset. Oestrogen is thought to provide a neuroprotective effect against the disease (Seena 1997).
What evidence is the hypothesis based on?
• What is the Treatment-Aetiology fallacy?
Cause Two: Brain Abnormality
Research involving MRI and CAT scan
research on live patients has found the
following structural abnormalities in the
schizophrenic brain.
Unusually large ventricles (fluid
filled cavities) (Brown et al 1986)
Cortical abnormalities like reduced
activity (red area) (Goldstein et al 1999)
25% reduction of grey matter in the
frontal & temporal lobes
(Kwon et al 1999)
Areas of the brain
Affected parts of the brain in a
schizophrenic patient
Lack of normal asymmetry in the
brains of schizophrenics Young et al
(1991)
(Possible) Cause Three: Viral
Theories
• Torrey & Peterson (1976) theorise that
contracting the influenza A virus in the 25-30
weeks of pregnancy, when the brain is in a
crucial stage of development, causes brain
damage which later manifests as schizophrenia.
• Not until puberty do hormonal changes reveal
the brain damage and from this age the brain
damage may manifest as schizophrenic
symptoms
Extended Activity
The following books/films depict Schizophrenic behaviour and activity
and are worth a watch:1.
A Beautiful Mind chronicled the life of John Forbes Nash, a NobelPrize-winning mathematician who was diagnosed with
schizophrenia.
2.
EastEnders featured a very successful storyline in 1996 that
involved a character suffering from schizophrenia, triggered by the
loss of a relative.
3.
In the book Misery by Stephen King, the antagonist Annie Wilkes
is thought to suffer from a form of schizophrenia, in addition to
other psychological disorders that makes her very argumentative
and not able to easily distinguish between fiction and reality.
You tube clip: Causes of Schizophrenia
http://www.youtube.com/watch?v=72kcxJyHlPM
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