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SCHIZOPHRENIA
Schizophrenia is most commonly characterized
by both 'positive symptoms' (those additional to normal
experience and behavior) and negative symptoms (the lack or
decline in normal experience or behavior). Positive symptoms are
grouped under the umbrella term psychosis and typically include
delusions, hallucinations, and thought disorder. Negative
symptoms may include inappropriate or lack of emotion, poverty
of speech, and lack of motivation. Some models of schizophrenia
include thought disorder and planning problems in a third
grouping, the 'disorganisation syndrome'. Additionally,
neurocognitive deficits may be present. These take the form of
reduction or impairment in basic psychological functions such as
memory, attention, problem solving, executive function and
social cognition. The onset is typically in late adolescence and
early adulthood, with males tending to show symptoms earlier
than females.
Psychiatrist Emil Kraepelin was
first to make the distinction between what he called dementia
praecox and other forms of madness. This classification was
later renamed 'schizophrenia' by psychiatrist Eugene Bleuler in
1911 as it became clear Kraepelin's name was not an adequate
description of the condition.
The diagnostic approach to
schizophrenia has been opposed, most notably by the
anti-psychiatry movement, who argue that classifying specific
thoughts and behaviors as illness allows social control of
people that society finds undesirable but who have committed no
crime.
More recently, it has been argued
that schizophrenia is just one end of a spectrum of experience
and behavior, and everybody in society may have some such
experiences in their life. This is known as the 'continuum model
of psychosis' or the 'dimensional approach' and is most notably
argued for by psychologist Richard Bentall and psychiatrist Jim
van Os.
Although no definite causes of
schizophrenia have been identified, most researchers and
clinicians currently believe that schizophrenia is primarily a
disorder of the brain. It is thought that schizophrenia may
result from a mixture of genetic disposition (genetic studies
using various techniques have shown relatives of people with
schizophrenia are more likely to show signs of schizophrenia
themselves) and environmental stress (research suggests that
stressful life events may precede a schizophrenic episode).
It is also thought that processes
in early neurodevelopment are important, particularly those that
occur during pregnancy. In adult life, particular importance has
been placed upon the function (or malfunction) of dopamine in
the mesolimbic pathway in the brain. This theory, known as the
dopamine hypothesis of schizophrenia largely resulted from the
accidental finding that a drug group which blocks dopamine
function, known as the phenothiazines, reduced psychotic
symptoms. These drugs have now been developed further and
antipsychotic medication is commonly used as a first line
treatment. However, this theory is now thought to be overly
simplistic as a complete explanation
From Wikipedia - The Free
Encyclopedia
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