Schizophrenia and other psychotic disorders

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Transcript Schizophrenia and other psychotic disorders

Schizophrenia and other
psychotic disorders
Schizophrenia
Schizophreniform Disorder
Schizoaffective Disorder
Delusional Disorder
Eugen Bleuler: Disturbances in
process of schizophrenia (1908)
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Bleuler emphasized the breaking of
associative threads, lack of purposeful
direction, and distractibility
Observed that there was not always
early onset or deteriorating course
More history of diagnosis
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Kurt Schneider: Pathognomic symptoms
– Emphasized the importance of
hallucinations and delusions in diagnosis
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Adolf Meyer (1917) and the American
experience
– A more flexible approach with subtypes
– Emphasized the process-reactive
dimension
A history of overdiagnosis
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Hoch (1949, 1955) added
pseudoneurotic schizophrenia and
pseudopsychopathic schizophrenia.
Schizophrenia became a catch-all
diagnosis, much more commonly
diagnosed in the United States than in
Great Britain.
DSM-III began to narrow the diagnostic
criteria
DSM-IV diagnostic criteria
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At least two characteristic symptoms:
– +Delusions *
– +Hallucinations *
– +Disorganized speech
– +Grossly disorganized or catatonic
behavior
– Negative symptoms
* Only one symptom required if it is bizarre
delusions or continually commenting or
conversing auditory hallucinations
More diagnostic criteria
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Significantly long-lasting marked
impairment of social or occupational
functioning or self-care.
Lasts for six continuous months,
including at least one month of active
phase symptoms
No major depressive, manic, or mixed
mood episodes
The syndrome duration
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Total duration must be at least 6 months
Prodrome Active Phase
Prodrome
Prodrome
Active Phase
Active Phase
Residual Phase
Residual Phase
Residual Phase
The active phase must last at least 1 month
Subtypes of schizophrenia
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Five types: Paranoid, disorganized,
catatonic, undifferentiated, residual
Paranoid type
– Preoccupied with one or more delusions,
or
– Frequent auditory hallucinations
– Speech, behavior, and affect are not
prominently impaired
Disorganized type (formerly
hebephrenic)
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Behavior and speech are disorganized
– Clang associations and neologisms
– Complete neglect of appearance
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Flat or rapidly changing inappropriate
emotion
Catatonic type
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At least two of
– Motor immobility
• Catalepsy
• Waxy flexibility
• Stupor
– Purposeless excess movement
– Extreme negativism: Motiveless resistance,
rigidity, mutism
– Strange movements: posturing,
stereotyped movements, grimacing
– Echolalia or echopraxia
Two more types
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Undifferentiated
Residual
Etiologies of schizophrenia
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The etiology may be complex, due to
– Broad set of symptoms
– Positive and negative symptoms
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Genetic factors in etiology
– 1% of general population
– 10% in first-degree relatives of probands
– 45% in identical twins of probands
– Same rate in children of probands (16.8%)
as in children of their non-schizophrenic
identical twins (17.4%) (Gottesman and
Bertelsen, 1989)
Etiological factors
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Inherited susceptibility or several genes
are involved
Retrospective strangeness in childhood
behavior
Stress trigger
Dopamine hyperactivity is found in
schizophrenia, but the genes for the five
types of DA receptors found so far are
not linked to schizophrenia (Coon et al.,
1993)
Environmental factors in etiology
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We will see that dopamine hyperactivity
relates to the positive symptoms of
schizophrenia.
The negative symptoms may be due to
brain damage: Some people with no
family history of schizophrenia or any
related disorder develop schizophrenia
Prenatal damage factors:
Epidemiology
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Incidence of schizophrenia increases
with:
– season of birth: late winter/early spring
– viral epidemics in second trimester
– population density and latitude
– malnutrition or refeeding after thiamine
deficiency (cf. Korsakoff’s syndrome)
– prenatal stress: WW II widows’ offspring
Evidence of brain damage in
schizophrenia
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Neurological symptoms
– Catatonia and facial dyskinesias
– Unusual rates of blinking, staring
– Avoidance of eye contact
– No blink reflex to a tap on the forehead
– Stopped speech w/ looking away, esp. to
right
– Jerky eye movements and poor visual
tracking
– Interdependence of eye and head
movements
– Impaired reaction of pupils to light changes
More evidence of brain damage
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Structural symptoms
– Doubling of size of lateral ventricles
– Abnormalities in temporal and frontal lobes
and in medial diencephalon
– Smaller anterior hippocampus: smaller
neurons
– Decreased gray matter in left temporal lobe
– Damage to left temporal lobe in adults may
produce schizophrenia de novo
– Low activity in prefrontal cortex
(hypofrontality)
Dopamine hypothesis
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Hypofrontality lowers tonic release of
DA
Nucleus accumbens DA receptors
become hypersensitive
Normal DA activity from VTA triggers
positive symptoms of schizophrenia
Drugs which treat schizophrenia lower
DA activity; increase Parkinsonism
Schizophreniform Disorder
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Same symptoms as Schizophrenia, but
lasts from 1 to 6 months
No decline in functioning is required for
this diagnosis
If the symptoms last less than one
month but more than one day, diagnose
Brief Psychotic Disorder
Schizoaffective Disorder
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A mood episode coincides with the
active phase of schizophrenia
Hallucinations or delusions occur for at
least two weeks before or after the
mood episode
The schizophrenias
Brief
Psychotic
Disorder
1
Schizophreniform Disorder
2
3
4
5
6
Months duration of symptoms
Schizophrenia
>6
Delusional Disorder
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Non-bizarre delusions for at least one
month
None of the other symptoms of
schizophrenia
Behavior not directly affected by the
delusions is normal
Subtypes of Delusional Disorder
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Erotomanic
Grandiose
Jealous
Persecutory
Somatic
Mixed
Shared Psychotic Disorder
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An otherwise unaffected person shares
the delusional beliefs of a person with a
psychotic disorder
Usually found only in long-term
relationships of dominant-passive
partners
Social isolation seems to be a
necessary feature
Disorganized speech
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aka Formal thought disorder
Incoherence
Loose associations
Derailment/distractibility
Perseveration
Disorganized speech 1
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“Takes less place. Cat didn’t know what
Mouse did and Mouse didn’t know what
Cat did Cat represented more on the
suspicious side than the mouse.
Dumbo was a good guy. He saw what
the cat did, put himself with the cat so
people wouldn’t look at them as
comedians. Cat and Dumbo are one
and alike, but Cat didn’t know what
Dumbo did and neither did the mouse.”
Disorganized speech 2
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“Everyone should have a good laugh.
Don’t cry over it. Don’t tell anyone -they will tell someone. Appreciate it
without criticism. A word like milk
shouldn’t be mentioned.”
Disorganized speech 3
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“So to beseech you as full as for it.
Exactly or as kings. Shutters shut and
open so do queens. Shutters shut and
shutters and so shutters shut and
shutters and so and so shutters and so
shutters shut and so shutters shut and
shutters and. So and so shutters shut
and so and also. And also and so and
so and also.”
Disorganized speech credits
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Disorganized speech 1 and 2 are from a
person with schizophrenia, quoted in
Zimbardo’s Instructor’s manual for
Psychology and Life.
Disorganized speech 3 is from a poem
by Gertrude Stein.
Grossly disorganized or catatonic
symptoms
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“Other symptoms” (Davison & Neale)
– Inappropriate affect
– Bizarre behavior
• Social blunders/residual rule-breaking
• Treasuring trash
– Immobility
– Waxy flexibility
Negative symptoms
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Behavioral deficits:
– Avolition
– Alogia
• Poverty of speech
• Poverty of speech content
– Anhedonia
– Flattened affect
• Monotone; less facial expression of emotion
– Asociality