Download Module 68 - Schizophrenia

Schizophrenia
What is Schizophrenia?
• Ability to function is impaired by severely distorted
beliefs, emotions, perceptions, & thought processes
• Comes from Greek meaning “split” and “mind”
– ‘split’ refers to loss of touch with reality - psychosis
– not dissociative state
– not ‘split personality’
• 1 in 100 people develop schizophrenia
– 24 million world wide
Symptoms of Schizophrenia
Positive (Additive) &
Negative (Subtractive) Symptoms
Disorganized Speech
• Word Salad - a string of words that vaguely resembles
language, and may or may not be grammatically correct,
but is utterly meaningless.
– “Tramway flogging into my question, are you why is it
thirty letters down under peanut butter, what is it.”
– Watch this example from Boston Legal (1 min)
• Neologisms - Making up words
– “I am going to the park to ride the wallywhoop.”
• Clang Speech - Rhyming all the words .
– “Deck the halls with boughs of holly, folly, polly,
dolly, hello Dolly, want a lollipop?”
• Echolalia - Repeating exactly what someone else has said
• Echopraxia - Repeating exactly what someone else has
done.
Disorganized Behavior
• Perseveration - Repeating the same activity (word
or behavior) over and over again.
• Dressing oddly, such as wearing many sets of
clothing one over the other or wearing hats,
gloves, and heavy coats in the summer.
• Doing things in public that are usually done only
in private.
– For example: urinating on a street corner.
Hallucinations – False Perceptions
• Auditory - hearing voices
– Most common
– Command hallucinations: voices
giving orders
• Visual – seeing things not
actually present
• Tactile – feeling skin sensations
• All of these contribute to
delusions
Disorganized Symptoms
• Disorganized thought
– Over-inclusion—jumping from idea to idea without the benefit of
logical association
– Paralogic—on the surface, seems logical, but seriously flawed
• e.g., Jesus was a man with a beard, I am a man with a beard, therefore I am
Jesus
– Maybe caused by a breakdown in selective attention
• Disorganized behavior and affect
– behavior is inappropriate for the situation
• e.g., wearing sweaters and overcoats on hot days
– affect is inappropriately expressed
• flat affect—no emotion at all in face or speech
• inappropriate affect—laughing at very serious things,
crying at funny things
– catatonic behavior
• unresponsiveness to environment, usually marked by
immobility for extended periods
Frequency of positive and negative symptoms in individuals at the time they were
hospitalized for schizophrenia. Source: Based on data reported in Andreasen &
Flaum, 1991.
Subtypes of Schizophrenia
• DSM 5 removed these subtypes and now uses a
spectrum of severity to classify schizophrenia
• Paranoid type
– delusions of persecution
• believes others are spying and plotting
– delusions of grandeur
• believes others are jealous, inferior, subservient
– no cognitive impairment, disorganized behavior, or negative
symptoms
• Catatonic type—unresponsive to surroundings,
purposeless movement, parrot-like speech
– waxy flexibility
– highly disturbed movements or actions
Subtypes of Schizophrenia
• Disorganized type
– delusions and hallucinations with little meaning
– disorganized speech, behavior, and flat affect
• Undifferentiated type – exhibits
symptoms of schizophrenia but can’t be fit
into one of the 3 subtypes.
Schizophrenia: An Example
• Watch Module 26 from The Brain dvd (5
min).
– Online Version (8 min)
• As you watch Gerald write down what
symptoms you see him demonstrating.
• What subtype of Schizophrenia would you
predict he has?
DSM 5 removed these subtypes
and now uses a spectrum of
severity to classify
schizophrenia.
They are helpful though in
remembering the different
kinds of symptoms that can
accompany the disorder.
Prevalence of Schizophrenia
• Onset of schizophrenia typically
occurs during young adulthood.
– Males have earlier onset
• 18 to 25 for men
• 26 to 45 for women
• Approximately 1.2% of Americans
(3.2 million) have the disorder
• Worldwide, about 1% of the
population will experience at least
one episode of schizophrenia at
some point in life
Course of Schizophrenia:
The ¼, ¼, ½ Rule
• Acute/Reactive Schizophrenia – develops rapidly usually
after a stressful event. High rate of recovery
• Chronic/Process Schizophrenia – develops slowly, often
with negative symptoms, low recovery rate
• Enormous individual variability
• About 1/4 of those who experience an episode of
schizophrenia recover completely
• Another 1/4 experience recurrent episodes, but often with
only minimal impairment of functioning
• The other 1/2, schizophrenia becomes a chronic mental
illness, and the ability to function normally in society may
be severely impaired.
Causes of Schizophrenia
POSSIBLE
BIOLOGICAL
FACTORS
The Dopamine Theory
• Theory: Schizophrenia is caused by
excess of receptors for dopamine
– Potential cause for positive symptoms
• Drugs that reduce dopamine reduce
symptoms
• Drugs that increase dopamine
(amphetamines & cocaine) can produce
symptoms even in people without the
disorder
• Dopamine theory not enough; other
neurotransmitters involved as well
Other Biological Factors
• About half the people with schizophrenia show
some type of brain structure abnormality
• Brain structure and function
– enlarged cerebral ventricles and reduced neural tissue around the
ventricles
• Shrinkage found in cortex, corpus callosum, & thalamus
– PET scans show reduced frontal lobe activity
– Increased activity in Thalamus (filters incoming info) when
experiencing hallucinations
– Increased activity in Amygdala for those with paranoia
Brain Activity & Tissue Loss
• One five-year prospective study compared brain structure
changes in normal adolescents and adolescents with early onset
schizophrenia
• Gray matter tissue loss ranged from about 1 percent in the normal
teens to more than 5 percent in the schizophrenic teens
• The amount of gray matter loss was directly correlated to the
teenage patient’s clinical symptoms
– More rapid gray matter losses in the temporal lobes were associated
with more severe positive symptoms
– More rapid gray matter losses in the frontal lobes were strongly
correlated with the severity of negative symptoms
• PET scans of brain activity during schizophrenic hallucinations
reveal activity in the left auditory and visual areas of the brain,
but not in the frontal lobe, which is normally involved in
organized thought processes.
The Shrinking of the Schizophrenic Brain
Among adolescents who suffer a
relatively rare childhood - onset
schizophrenia, MRI scans by Paul
Thompson and his colleagues
(2001) revealed a much-greaterthan-normal loss of cerebral cortex
tissue between the ages of 13 & 18
Overpruning Results in Enlarged
Ventricles
Not Just Brain Abnormalities at Fault
• Some people with schizophrenia do not show brain
structure abnormalities
• The evidence is correlational
• The kinds of brain abnormalities seen in
schizophrenia are also seen in other mental
disorders
POSSIBLE
ENVIRONMENTAL
FACTORS
Viral Infection Theory
• Might be caused by exposure to an influenza virus or other
viral infection during prenatal development or shortly after
birth
• Children whose mothers were exposed to a flu virus during
the second trimester of pregnancy show an increased rate of
schizophrenia
• Schizophrenia occurs more often in people who were born
in the winter and spring months, when upper respiratory
infections are most common
• One study found traces of retrovirus in nearly half of
people with schizophrenia while finding virtually none in
healthy people.
Malnutrition & Schizophrenia
• Children who were in their mothers' wombs during the period of great
famine in China later developed schizophrenia at roughly twice the
usual rate. (Data from St. Clair & others, 2005.)
• Maternal stress may “turn on” genes that predispose schizophrenia
GENETIC
FACTORS
Schizophrenia and Genetics
Risk increases with genetic similarity
50
40
40
Lifetime risk
of developing
schizophrenia
for relatives of
a schizophrenic
30
30
20
10
10
0
0
Fraternal Children
Identical
of two
twin
General
Siblings
twin
Children
schizophrenia
population
victims
Developing Schizophrenia
The lifetime risk of developing schizophrenia varies with one's genetic
relatedness to someone having this disorder. Across countries, barely
more than 1 in 10 fraternal twins, but some 5 in 10 identical twins, share
a schizophrenia diagnosis. (Adapted from Gottesman, 2001.)
The Heritability of Schizophrenia
The researchers looked for signs
of schizophrenia in the
biological and adoptive relatives
of people who had been adopted
at an early age and either did or
did not subsequently develop
schizophrenia.
The results here are the
percentage of relatives who
showed either schizophrenia or
a milder disorder now called
schizotypal personality disorder.
(Data from Kety & others,
1976.)
POSSIBLE
PSYCHOLOGICAL
FACTORS
Unhealthy Family Environment
• Individuals who are genetically predisposed to
develop schizophrenia may be more vulnerable to
the effects of disturbed family environments
Finnish Adoptive Family Study of
Schizophrenia
• Found that children whose biological mother had schizophrenia
had a much higher rate of schizophrenia than did the control group
when they were raised in a psychologically disturbed adoptive
family
• When raised in a psychologically healthy adoptive family, they
were no more likely than the control group to develop
schizophrenia.
• One-third of the adopted children with no genetic history of
schizophrenia developed symptoms of a serious psychological
disorder if they were raised in a psychologically disturbed family
environment
• Conclusion: a healthy psychological environment may counteract a
person’s inherited vulnerability for schizophrenia, but a
psychologically unhealthy family environment can act as a catalyst
for the onset of schizophrenia
Other Family Influences on
Schizophrenia
Dysfunctional Family variables:
– parental communication that is
disorganized, hard-to-follow, or highly
emotional
– expressed emotion
• highly critical, over-enmeshed families
Possible Early Warning Signs of
Schizophrenia
• A mother whose schizophrenia severe & long
lasting
• Birth complications – oxygen deprivation or low
birth weight
• Separation from parents
• Short attention span & poor muscle coordination
• Disruptive or withdrawn behavior
• Emotional unpredictability
• Poor peer relations or solo play
Development Model of Schizophrenia
This model depicts
researchers'
understanding of the
contributions of genes,
environmental
experiences, and the
person's present neural
and behavioral condition
to the development of
schizophrenia and, in
some cases, its
progression into a
chronic condition. (Based
on a model depicted by
Tsuang & others, 2001)
Summary of Schizophrenia
• Many biological factors seem involved
– heredity
– neurotransmitters
– brain structure abnormalities
• Family and cultural factors also important
• Combined model of schizophrenia
– biological predisposition combined with psychosocial
stressors leads to disorder
– Is schizophrenia the maladaptive coping behavior of a
biologically vulnerable person?