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Chapter 12 - Schizophrenia
Psychosis
 Psychosis: a loss of contact with reality
 Ability to perceive and respond to the environment
significantly disturbed; functioning impaired
 Symptoms may include hallucinations (false sensory
perceptions) and/or delusions (false beliefs)
Schizophrenia
◦ Individuals must show a deterioration in their work,
social relations, and ability to care for themselves
◦ Six months or more
Schizophrenia
◦ Affects approximately 1 in 100 people in the world
◦ Financial & emotional costs: enormous
◦ Increased risk of suicide and physical – often fatal –
illness
Schizophrenia
appears in all socioeconomic groups, but is
found more frequently in the lower levels
“downward drift”
Schizophrenia
 average age of onset for ♂ is 23 years, compared
to 27 years for ♀; book states = numbers; other
sources ♂ > ♀
 Rates of diagnosis differ by marital status
The Clinical Picture
◦ symptoms, triggers, and course vary greatly
◦ Some argue: group of distinct disorders that share
common features
Positive Symptoms
Pathological
excesses bizarre
additions to a
person’s
behavior
•Excess or
distortion in
normal
repertoire of
behavior
and
experience
Delusions
• Erroneous belief
• Fixed and firmly held despite
clear contradictory evidence
• Disturbance in the content of
thought
• Grandeur
• Persecution
• Reference
• Nihilistic
• Thought Broadcasting
Delusions
Hallucinations
• False Sensory
experiences/Perceptual
disturbances
• Seems real but occurs in
absence of any external
perceptual stimulus
• Can occur in any sensory
modality
Hallucinations
Disorganized Speech
• Failure to make sense
• Despite conforming to
semantic and syntactic
rules of speech
• Disturbance in form (not
content) of thought
Disorganized
speech
Disorganized Behavior
• Impairment of goaldirected activity
• Occurs in areas of daily
functioning
• Catatonia
• Catatonia stupor
• Inappropriate affect
Disorganized and
Catatonic Behavior
Negative Symptoms
Absence
or deficit
of
normally
present
behaviors
• Affective flattening,
Blunted affect
• Anhedonia
• Apathy
• Both a symptom
and coping
strategy
• Avolition
• Alogia
Neurocognition
Neurocognitive
deficits found
in people with
schizophrenia
Attentional
and working
memory
deficits
Eye-tracking
dysfunctions
Course
usually first appears between late teens and
mid-30s
three phases:
Prodromal
Active
Residual
DIATHESIS STRESS MODEL:
A Synthesis
Multiple
genetic
factors
Environmental
factors
Current thinking
emphasizes interplay
CAUSES
TWIN STUDIES
 The average concordance
rate for MZ twins is 48%,
whereas the comparable
figure for DZ twins is 17%.
 Suggests strong genetic
factors.
 Also compelling evidence for
the importance of
environment.
 Genain quadruplets
ADOPTION STUDIES
◦ Genetic factors play
role in development
of the disorder
(Heston).
Biological Views
Biological Views
Genetic factors may lead to the development of
schizophrenia through two kinds of (potentially
inherited) biological abnormalities:
◦ Biochemical abnormalities
◦ Abnormal brain structure
BIOLOGICAL CAUSES
The dopamine hypothesis
Interactions of multiple
neurotransmitters
◦ Focuses on the function
of dopamine in the
limbic area of the brain.
◦ Current research
focuses many
neurotransmitters:
◦ Dopamine
◦ Serotonin
◦ Glutamate
◦ Hypothesis grew out of
attempts to understand
how antipsychotic drugs
improve adjustment.
Prenatal Exposures
Prenatal
exposures:
Prenatal viral infection
Early nutritional deficiencies
and maternal stress
Pregnancy and birth
complications
Cytoarchitecture
•Overall organization of cells in brain may be compromised
Biological Views
Abnormal brain structure
 enlarged ventricles
 enlargement may be a
sign of poor
development or
damage in related brain
regions
 smaller temporal and
frontal lobes, smaller
amounts of grey matter,
and abnormal blood
flow to certain brain
areas
Sociocultural Views
 Social labeling
 Many sociocultural theorists believe that the features
influenced by diagnosis itself
 Society labels people who fail to conform to certain
norms of behavior
 Once assigned, label becomes a self-fulfilling
prophecy
 The dangers of social labeling have been well
demonstrated
 Example: Rosenhan’s 1973 “pseudo-patient” study
Sociocultural Views
 Family dysfunctioning
 often linked to family stress:
 Parents of people with the disorder often:
 Display more conflict
 Have greater difficulty communicating
 Are more critical of and overinvolved
 Family theorists have long recognized that
some families are high in “expressed emotion” –
family members frequently express criticism and
hostility and intrude on each other’s privacy
 Individuals who are trying to recover almost
four times more likely to relapse if they live with
such a family
Treatment: Antipsychotic Drugs
◦ the discovery of antipsychotic drugs in 1950s
that revolutionized treatment for those
suffering from schizophrenia
◦ Have a relatively specific effectreduce psychotic symptoms
◦ Work as dopamine antagonist
◦ Positive symptoms respond better than
negative symptoms.
reduce symptoms in at least 65% of
patients
 Motor Side Effects (parkinsonian symptoms)
○Extrapyramidal symptoms
○Tardive dyskinesia
 Second-Generation Antipsychotics
○ Atypical antipsychotics
○ Work on both serotonin and dopamine
○ Impact both positive and negative
symptoms
○ Examples: Clozaril, Risperdal, Zyprexa,
Seroquel, Geodon, and Abilify
Newer Antipsychotic Drugs
 appear more effective than conventional
antipsychotic drugs, especially for negative
symptoms
 cause few extrapyramidal side effects and seem
less likely to case tardive dyskinesia
 Some, however, do produce significant
undesirable effects of their own
Cognitive-behavioral therapy
 Clinicians employ techniques that
seek to change how individuals
view and react to their
hallucinatory experiences,
including:
 Provide education and evidence
of the biological causes of
hallucinations
 Challenge clients’ inaccurate
ideas about the power of their
hallucinations and delusions
Family therapy
◦ Over 50% of persons recovering from schizophrenia
and other severe disorder live with family members
◦ This creates significant family stress
◦ Those who live with relatives who display high
levels of expressed emotion are at greater risk for
relapse than those who live with more positive or
supportive families
Family therapy
◦ Family therapy
◦ Family therapy attempts to create more realistic
expectations and provide psychoeducation about
the disorder
Social Therapy
 Treatment should include techniques that address
social and personal difficulties
 include: practical advice, problem solving,
decision making, social skills training, medication
management, employment counseling, financial
assistance, and housing