Categorizing Schizophrenia

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TA B L E
Chapter 12 Psychological Disorders
12.4
Type
Frequency
Prominent Features
Paranoid
schizophrenia
40 percent of people with
schizophrenia; appears late
in life (after age 25–30)
Delusions of grandeur
or persecution;
anger; anxiety;
argumentativeness;
extreme jealousy; onset
often sudden; signs
of impairment may be subtle.
Disorganized
schizophrenia
5 percent of all people
with schizophrenia; high
prevalance in homeless
population
Delusions; hallucinations;
incoherent speech; facial
grimaces; inappropriate
laughter/giggling; neglected
personal hygiene; loss of
bladder/bowel control.
Catatonic
schizophrenia
8 percent of all people with
schizophrenia
Disordered movement,
alternating between total
immobility (stupor) and
wild excitement. In
stupor, the person does
not speak or attend to
communication.
Undifferentiated
schizophrenia
40 percent of all people
with schizophrenia
Patterns of disordered
behavior, thought, and
emotion that do not fall
easily into any other
subtype.
Residual
schizophrenia
Varies
Applies to people who
have had prior episodes of
schizophrenia but are not
currently displaying
symptoms.
Subtypes of Schizophrenia
These traditional categories of schizophrenia convey some useful information, but
subtype labels are not always accurate.
Some symptoms of schizophrenia appear in
more than one subtype, and people first
placed in one subtype might later display
characteristics of another. These concerns,
plus the fact that DSM-IV subtypes may not
be linked to different causal factors, have
led researchers to develop additional ways
of categorizing schizophrenia, such as
whether positive or negative symptoms are
most prominent in a given case (Villalta-Gil
et al., 2006).
Categorizing Schizophrenia
DSM-IV lists five major subtypes of schizophrenia: paranoid, disorganized, catatonic,
undifferentiated, and residual. These subtypes are summarized in Table 12.4.
Researchers have also made other useful distinctions among various forms of schizophrenia. One of these distinctions involves the positive-negative symptom dimension.
Disorganized thoughts, delusions, and hallucinations are sometimes called positive
symptoms of schizophrenia, because they appear as undesirable additions to a person’s
mental life (Andreasen et al., 1995; Racenstein et al., 2002). In contrast, the absence of
pleasure and motivation, lack of emotion, social withdrawal, reduced speech, and other
deficits seen in schizophrenia are sometimes called negative symptoms, because they
appear to subtract elements from normal mental life (Nicholson & Neufeld, 1993).
Many patients exhibit both positive and negative symptoms, but when the negative
symptoms are stronger, schizophrenia generally has a more severe course, including
long-term disability and relative lack of response to treatment (e.g., Milev et al., 2005;
Racenstein et al., 2002). Yet another way of categorizing schizophrenic symptoms
focuses on whether they are psychotic (e.g., hallucinations, delusions), disorganized (e.g.,
incoherent speech, chaotic behavior, inappropriate affect), or negative (e.g., lack of
speech or motivation). Some researchers believe that each symptom cluster or dimension may ultimately be traceable to different causes. For this reason, schizophrenia is
often referred to as the schizophrenia spectrum (Tsuang, Stone, & Faraone, 2000).