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Chapter 14:
Schizophrenia:
The Most Dreaded Illness
Abnormal Psychology
Mar 12 & 24, 2009
Classes #17-18
Etiology
► Schizophrenia
is a disease of the brain
► Changes in neurophysiological function that
characterize schizophrenia have been
identified
► Exact causes:
 Unknown
► Prevention:
 Unknown
Prevalence and Onset
► 1%
of the general population
► Onset:
 Young adulthood (although late onset is
possible)
Risk Factors
► Equal
numbers of men are women are
diagnosed
 In men, symptoms begin earlier and are more
severe
► Rates
of diagnosis differ by marital status
 3% of divorced or separated people
 2% of single people
 1% of married people
►It
is unclear whether marital problems are a cause or
a result
Risk Factors
► Rates
of the disorder differ by ethnicity and race
 About 2% of African Americans are diagnosed,
compared with 1.4% of Caucasians
► According
to the census, however, African Americans are also
more likely to be poor and to experience marital separation
► When controlling for these factors, rates of schizophrenia are
equal for the two racial groups
► Genetic
factors appear to play a role
 We’ll take a close look at the numbers later
Famous People Diagnosed
Nash portrayed in media: “He saw the world in a way no one
could have imagined”
DSM-IV Diagnostic Criteria
1. Individual has two or more of the following for a significant
portion of time during a 1-month period (or less if
successfully treated):
a. Delusions
b. Hallucinations
c. Disorganized speech
d. Grossly disorganized behavior or catatonic behavior
e. Negative symptoms (affective flattening, alogia, or
avolition)
2. Individual shows a decline in social or
occupational functioning
3. Symptoms persist for at least 6 months. This 6-month period
must include at least 1 month of symptoms (or less if
successfully treated) that might criterion A (active-phase
symptoms) and may include prodromal or residual
symptoms.
4. Other psychotic disorders and medical conditions
have been ruled out
Diagnosis
► The
diagnosis of this disorder is difficult and
controversial…
 Schizophrenia is a "diagnosis of exclusion" which is
made if no other psychotic disorder can account for the
type of symptoms and their duration
► The
following factors may suggest a schizophrenia
diagnosis but do not confirm it:
 Developmental background
 Genetic and family history
 Changes from level of functioning prior to illness
Types of Schizophrenia
► Paranoid
► Disorganized
► Catatonic
► Undifferentiated
► Residual
Paranoid type
► Delusional
thoughts of a persecution or
grandiose nature
► Anxiety
► Anger
► Violence
► Argumentative
Disorganized type
► Incoherence
(not understandable)
► Regressive behavior
► Flat Affect
► Delusions
► Hallucinations (mostly auditory)
► Inappropriate Laughter
► Mannerisms
► Social Withdrawal
Catatonic type
► Motor
disturbances
► Stupor
► Negativism
► Rigidity
► Excitement
► May be unable to take care of personal needs
► Decreased sensitivity to painful stimulus
Undifferentiated type
► May
have symptoms of more than one
subtype of schizophrenia
Residual type
► The
prominent symptoms of the illness have
abated but some features, such as
hallucinations and flat affect, may remain
Symptoms of Schizophrenia
► Cognitive
symptoms
 Hallucinations
 Delusions
►Delusions
►Delusions
►Delusions
►Delusions
►Delusions
of
of
of
of
of
persecution
reference
identity
grandiosity
thought-broadcasting
Symptoms of Schizophrenia
► Cognitive
symptoms
 Disturbed thought processes
►Word
salad
►Dementia praecox
►Schizophrenic deficit
 Cognitive flooding (stimulus overload)
Symptoms of Schizophrenia
► Mood
symptoms
 Depression
 Inappropriate emotional responses
► Physical
symptoms
 Effects of drugs
 Motor symptoms
Positive and Negative
Symptoms of Schizophrenia
Schizophrenia
Positive Symptoms
Psychoticism
• Hallucinations
• Delusions
• Heightened perceptions
Disorganization
• Thought disorders
• Bizarre behaviors
• Inappropriate affect
• Loose associations
• Neologisms
• Clang Associations
Copyright 2001 by Allkyn and Bacon
Negative Symptoms
• Blunted and Flat Affect
• Poverty of speech (alogia)
• Inability to experience
positive feelings
• Apathy
• Inattentiveness
20
Characteristics Associated with
Positive and Negative Symptoms
Characteristic
Positive symptoms
Negative symptoms
Onset
Later
Earlier
Stability over time
Symptoms fluctuate
Symptoms consistent
over time
Frequency of
occurrence
More frequent in
More frequent in
Response to
treatment
women
men
Good
Copyright 2001 by Allkyn and Bacon
Poor
21
Issues Associated with Schizophrenia
► Sociocultural




factors
Age
Gender
Ethnicity
Socioeconomic class
►Downward social drift
►Bias in diagnosis
►Bias in treatment
►Bias in self-presentation
Explanations for Schizophrenia
► Psychodynamic
explanations
 Problems with child-rearing
 Stress
Physiological Explanations
►
►
►
►
Problems with Neurotransmitters
 The Dopamine Theory
 The Serotonin Explanation
►Positive symptoms
►Negative Symptoms
 High Neurological Activity and Symptoms
►Prefrontal Cortex
►Temporal Cortex
Problems with Brain Development and Activity
Genetic Factors
Biological Traumas
Carlsson & Lindqvist (1963)
► The
Dopamine Theory
 Speculated that an abnormality in the brain
processes causes there to be an excess of
dopamine
 A high level of dopamine receptors is related to
positive symptoms
The Dopamine Explanation
► L-dopa
 Used to treat Parkinson’s patients who are
thought to have too low levels of dopamine
causing motor problems
 Unfortunately, although it helps with the motor
problems it also can produce positive symptoms
of schizophrenia in these individuals
The Serotonin Explanation
(Positive Symptoms)
► When
serotonin levels are low, inhibitory
neurons become underactive and do not
reduce the activity of the excitatory neurons
► Thus, the activity of the excitatory neurons
becomes to high and we see positive
symptoms
The Serotonin Explanation
(Negative Symptoms)
► Low
levels of serotonin can contribute to negative
symptoms of schizophrenia because these low
levels can cause depression
► The depression then provides the basis for the
negative symptoms (apathy, poverty of thought,
etc.)
High Neurological Activity and Symptoms
► Prefrontal
Cortex
 This is where information from different parts of
the brain is integrated and where thought
processes occur
 Too much activity here causes positive
symptoms (thought processes are disrupted)
► Evidence
 Pet Scans
 “Angel Dust”
High Neurological Activity and
Symptoms
► Temporal
Cortex
 This is where memories for auditory and visual
experiences are stored
 High activity here can activate those memories and
result in hallucinations
 Causing people to believe that they are really hearing
voices
High Neurological Activity and
Symptoms
► PET
scans reveal higher brain activity when people
are hallucinating
► Strong evidence linking high neurological activity
in prefrontal and temporal cortexes with positive
symptoms
Hallucinations are associated with neuronal activity
Specific neuronal circuits involving the
thalamus, caudate-putamen, anterior
cingulate, limbic cortex,
auditory cortex,
hippocampus and parahippocampal
gyrus are activated in schizophrenics
during auditory hallucinations.
Part of Figure 60-2
Gross neuroanatomical abnormalities in schizophrenia
Increased size of cerebral ventricles
(lateral and 3rd) and
decreased brain volume is the
most replicated finding.
Ventricular enlargement is
found in affected twins of
monozygotic pairs discordant
for schizophrenia.
This enlargement appears to
be stable when patients are
followed up prospectively.
Unaffected twin
Figure 60-5
Schizophrenic twin
Decreased cortical gray matter (not shown here)
Especially evident in superior temporal gyrus, dorsal prefrontal cortex and limbic areas
such as the hippocampal formation and anterior cingulate cortex.
These abnormalities may be present in first-episode, never-medicated patients.
Cellular neuronal abnormalities in schizophrenia (not shown here)
Decreased numbers of neurons have been found in the hippocampus and the
dorsolateral prefrontal cortex.
In studies of monozygotic twins discordant for schizophrenia, there is
diminished activation of the dorsolateral prefrontal cortex as measured by
SPECT and PET.
Unaffected
Subcellular neuronal
abnormalities in schizophrenia
Abnormal dendridic spines in
prefrontal cortex- layer 3
Schizophrenic #1
Schizophrenic #2
Problems with Brain
Development and Activity
► Neurodevelopmental
Theory
 This theory suggests that areas of the brain do not
develop adequately and/or deteriorate faster than
normal
►Proposes that a proportion of schizophrenia is
the result of an early brain insult
 For example: difficult pregnancy, mother near
starvation during pregnancy, flu during
pregnancy, etc. (Mednick, 1970)
Problems with Brain
Development and Activity
► Specific
problems with brain structures causing
negative symptoms
 Reversed hemispheric dominance
►For most people their left hemisphere is larger
►Not so for many schizophrenia patients
►Idea here is that since the left (more verbal and
analytical) is underdeveloped leading to negative
symptoms
Problems with Brain
Development and Activity
► Specific
problems with brain structures causing
negative symptoms
 Failure of Neural Migration
► Neurons
are not in right places
► This occurs during prenatal development and briefly after birth
 Cortical Atrophy -- Progressive loss or deterioration of neurons
► Cerebral
cortex is somewhat shrunken in about one-third of
schizophrenics
► Cerebral ventricles are enlarged (these are canals that go through the
brain and carry away waste materials)
► Basically, is a sign of brain deterioration and causes a loss of neurons
(found in at least 20% of schizophrenics)
Problems with Brain
Development and Activity
► Hypofrontality
 Prefrontal cortex is underactive causing
negative symptoms
Genain Quadruplets: 1 in 100,000,000
History of Treatment of
Schizophrenia
• Psychosurgery
– Prefrontal Lobotomy
(introduced in 1935)
Transorbital Lobotomy (introduced in 1948)
Referred to as “the icepick lobotomy”
• Before
• During
Transorbital Lobotomy
• After
History of Drug Treatment of
Schizophrenia
► Until
the mid-1950’s the prognosis for
schizophrenics was very unfavorable
► Most were institutionalized for the rest of
their lives in large mental hospitals
 Only about 30% would ever be discharged after
entering
History of Drug Treatment of
Schizophrenia
► Medications
brought tremendous “overnight”
change -► Chlorpromazine was the first
 These drugs don’t cure the illness but often can control
it
 Originally referred to as “mild tranquilizers”
Contemporary Treatments
Today, a schizophrenia patient is often treated in an
outpatient clinic and those that enter a mental institution
have about a 90% chance of being discharged in a matter
of weeks or months
► The primary goal of modern drug therapy is to reduce the
high level of neurological activity
► This is accomplished with a group of drugs called
neuroleptics
►
 These drugs block the receptors on the postsynaptic neuron so that
dopamine cannot enter the receptor and cause the neuron to fire
 These drugs also reduce the sensitivity of the postsynaptic receptors – less
sensitive, less likely to fire.
 Some of the newer neuroleptics also increase the levels of serotonin
Types of Neuroleptics
► Neuroleptics
 Low-potency Neuroleptics
► Mellaril
► Thorazine
 High-potency Neuroleptics
► Haldol
► Navane
 Atypical Neuroleptics
► Clozaril
► Risperidal
► Zyprexa
Low-Potency Neuroleptics
► Popular
in 1960’s – 1970’s
► Blocks 75%-80% of dopamine receptors
► Helps with positive symptoms but not with
negative symptoms
High-Potency Neuroleptics
► These
drugs released in 1970’s
► Blocks about 80% of dopamine receptors
► Much more effective than LP meds but at a price
► Drastic side-effects
 Parkinson-type symptoms
► No
help with negative symptoms
Atypical Neuroleptics
►
►
►
►
►
Released in 1980’s (Clozaril)
Block less dopamine receptors (about 65%)
More selective in their blocking
 Block receptors leading to frontal and temporal lobes (as the LP
and HP drugs do) but block fewer receptors in nerve tracts
associated with movement
Help with negative symptoms
 Increases serotonin levels which can also help reduce dopamine
activity
 Can also reduce depression associated with illness
Side-effect:
 About 2% of those taking Clozaril experience sudden drop of white
blood cells
► Newer drugs (Risperidal and Zyprexa) do not cause this
 Big developments in 1990’s
Atypical Neuroleptics
► So
why don’t why only use these now???
Side Effects of Drug Therapy
► Mild






symptoms
Dryness of mouth or excessive salivation
Blurred vision
Grogginess
Constipation
Sensitivity to light
Reduced sexual arousal
Side Effects of Drug Therapy
►
More serious symptoms
 Tardive Dyskinesia
►Involuntary muscle movements
 Akathisia
►Inability to sit still
 Malignant Neuroleptic Syndrome
►Muscular rigidity
►Very high temperature leading to brain damage
►Fluctuating blood pressure leading to stroke or coma
►Most likely to occur with high-potency neuroleptics
►Occurs more often in women
►Is very rare as it occurs in less than 1% of patients
taking these drugs
Complications
► Noncompliance
► Physical
with medication
illness
► Substance abuse
► Depression
► Suicide
Prognosis
►
Bad news
 Unfortunately, the rate of readmission is extremely high as about
two-thirds again need help
►
Good news
 About one-third recover
 Which technically means that they remain symptom-free for five
years
►
Bad news
 Problems with non-compliance
 These drugs are a life-long situation as patients that stop taking
the drugs will see the symptoms return and most often worsen
Other Psychotic Disorders
► Brief
Psychotic Disorder
► Schizophreniform Disorder
► Schizoaffective Disorder
► Delusional Disorder
► Shared Psychotic Disorder
► Psychotic Disorder due to a general medical
condition
► Substance-induced Psychotic Disorder
Credits
http://www.dmacc.cc.ia.us/instructors/acstevens/241ppts/comer5e_lecture_Ch
14.ppt#314,2,Psychosis
► http://www.its.caltech.edu/~lester/Bi-150/Lecture-23-2007-BiCNS150.ppt#408,6,Slide 6
►