Download Schizophrenia

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Document related concepts

Emil Kraepelin wikipedia, lookup

E. Fuller Torrey wikipedia, lookup

Mechanisms of schizophrenia wikipedia, lookup

Transcript
Ch. 18 Section 6: Schizophrenia
Obj: Describe the subtypes of
schizophrenia.
• Schizophrenia – usually considered the most
serious of the psychological disorders, is
characterized by loss of contact with reality.
Schizophrenia can be very disabling, and even
lead to the affected person’s inability to
function independently. Typically,
schizophrenia first appears in young
adulthood, but it may occur at other ages.
Although it usually develops gradually, it can
also appear suddenly. Schizophrenia can now
be treated more effectively, although if
untreated it can worsen over time.
The most obvious symptoms of schizophrenia include
hallucinations, delusions, and thought disorders. In most
cases, the hallucinations are auditory – voices may tell
the individual what to do or comment on the individual’s
behavior. Sometimes the voices may tell the individual to
harm herself or himself or others.
Individuals with schizophrenia may experience
delusions of grandeur – beliefs that they are
superior to other people. For example, such
individuals may believe that they are famous
or on a special mission to save the world.
Sometimes the delusions are of persecution.
For example, a person with schizophrenia
might believe that he or she is being pursued
by the CIA, FBI, or some other government
agency. Other delusions may include beliefs
that one has committed unpardonable sins or
even that one does not really exist.
Thought disorders involve problems in the
organization or the content of mental
processes. The thoughts of a person with
schizophrenia may skip from topic to topic in
an apparently illogical way. This is reflected in
the person’s speech, which sounds
disorganized and confused. A person with
schizophrenia may also repeat the same word
or phrase over and over, repeat words or
phrases that another person has spoken, or
invent new words.
People with schizophrenia experience other
symptoms that result in a decreased ability to
function. These symptoms include social
withdrawal, loss of social skills, and loss of
normal emotional responsiveness. Some
people with schizophrenia may even go into a
catatonic stupor – an immobile,
expressionless, comalike state.
Understandably, these symptoms cause
tremendous stress to individuals with
schizophrenia and their families. It has been
estimated that as many as 20 percent of
people with schizophrenia attempt suicide
and that 10 percent actually do kill
themselves.
Schizophrenia is found in all cultures and has
been recognized for several thousand years. A
large number of people have schizophrenia –
an estimated 2 million in the US alone.
Types of Schizophrenia
Individuals with schizophrenia vary greatly in
symptoms they exhibit, although virtually all
have thought disorders. Most people with
schizophrenia exhibit a combination of
symptoms.
The DSM-IV classification of schizophrenia and
other psychotic disorders is based on the
duration and recurrence of symptoms. The
types of schizophrenia include paranoid,
disorganized, and catatonic schizophrenia.
• Paranoid Schizophrenia – People with paranoid
schizophrenia have delusions or frequent
auditory hallucinations, all relating to a single
theme. These people may have delusions of
grandeur, persecution, or jealousy. For example,
an individual with paranoid schizophrenia may be
convinced that people have been plotting against
him or her even when there is no evidence of
such. Although people with this type of
schizophrenia tend to have less disordered
thoughts and bizarre behavior than do people
with other types of schizophrenia, they may be
agitated, confused, and afraid.
• Disorganized Schizophrenia – People with
disorganized schizophrenia are incoherent in
their thought and speech and disorganized in
their behavior. They usually have delusions or
hallucinations as well, but these tend to be
fragmentary and unconnected, unlike the
more ordered and systematic delusions of
those with paranoid schizophrenia.
People with disorganized
schizophrenia are also
either emotionless or
show inappropriate
emotions. Typically, they
act silly and giddy, and
they tend to giggle and
speak nonsense. They
may neglect their
appearance and hygiene
and even lose control of
their bladders and
bowels.
• Catatonic Schizophrenia – The most obvious
symptom of catatonic schizophrenia is
disturbance of movement. Activity may slow
to a stupor and then suddenly switch to
agitation. Individuals with this disorder may
hold unusual, uncomfortable body positions
for long periods of time, even after their arms
and legs swell and stiffen. They may also
exhibit waxy flexibility, a condition in which
other people can mold them into strange
poses that they continue to hold for hours.
Explaining Schizophrenia
Many different theories
have been proposed to
explain schizophrenia.
These theories include
both psychological and
biological views.
• Psychological Views – According to the
psychoanalytic perspective, schizophrenia is the
result of the overwhelming of the ego by urges
from the id. The urges threaten the ego and
cause intense conflict. In response, the individual
regresses to an early phase of the oral stage of
development in which the infant has not learned
that it is separate from the mother. In this
condition, fantasies become confused with
reality, leading to hallucinations and delusions.
Like many psychoanalytic theories, this one has
fallen into disfavor over the years.
Other psychological views focus on the family
environment as the root of schizophrenia. One
such theory suggests that a family
environment in which a parent frequently
expresses intense emotions and has a pushy,
critical attitude puts children at risk of
developing schizophrenia. It is possible,
however, that such a family environment may
only increase the chances of relapse in
individuals who have schizophrenia. That is to
say the family environment does not actually
produce schizophrenia.
• Biological Views – schizophrenia appears to be a
brain disorder, and many studies have been done
to determine how the brains of schizophrenic
people differ from those of other people. One
avenue of brain research connects the major
problems found in schizophrenia – problems in
attention, memory, abstract thinking, and
language – with differences in the frontal part of
the brain. Schizophrenic people have smaller
frontal region. Research suggests that the
difficulties may reflect a loss of synapses, the
structures that connect neurons to communicate
with one another.
What might cause the loss of synapses?
Research evidence suggests that there are
three biological risk factors: heredity,
complications during pregnancy and birth, and
birth during winter. Schizophrenia, like many
other psychological disorders, runs in families.
People with schizophrenia constitute about 1
percent of the population. However, children
with one parent who has been diagnosed as
schizophrenic have about a 10 percent chance
of being diagnosed as schizophrenic
themselves.
Children with two such parents have about a 35
to 40 percent chance of being so. When one
identical twin has it, the other has about a 40
to 50 percent chance of being diagnosed with
it. Many studies have been carried out to try
to isolate the gene or genes involved. Some
studies have found locations for multiple
genes on several chromosomes. Recent
research suggests that particular genes may
provide the vulnerability to schizophrenia.
Many people with schizophrenia have experienced
complications during pregnancy and birth. For
example, the mothers of many people with
schizophrenia had influenza during the sixth or
seventh month of pregnancy. People with the
disease are also somewhat more likely to have
been born during the winter than would be
predicted by chance. Maternal starvation has also
been related to schizophrenia. These biological
risk factors suggest that schizophrenia involves
abnormal prenatal brain development.
Problems in the central nervous system may
involve neurotransmitters as well as brain
structures, and research has focused on one
particular neurotransmitter: dopamine.
According to the dopamine theory of
schizophrenia, people with schizophrenia use
more dopamine than other people do,
although they may not produce more of it.
Why? They may have more dopamine
receptors in the brain than other people, or
their dopamine receptors may be hyperactive.
• A Multifactorial Model of Schizophrenia – The
multifactorial model of schizophrenia illustrates
how several biological and psychological factors
may interact in the development of the disorder.
In this model, genetic factors create a
vulnerability, or susceptibility, to schizophrenia.
Among people who are genetically vulnerable,
other factors, such as trauma during birth, may
lead to brain injury and the subsequent
development of schizophrenia. Once the disorder
develops, its course may be negatively affected
by the family environment.
The model also suggests
that environmental
factors alone are not
enough to lead to the
development of
schizophrenia. Thus,
people who are not
genetically vulnerable
are unlikely to develop
the disorder, regardless
of the environmental risk
factors to which they are
exposed.