540 CHAPTER 12
Key Concepts and Facts About What are Schizophrenia and Other Psychotic Disorders?
- According to DSM-IV-TR, schizophrenia is characterized by two
or more symptoms, at least one of which must be positive;
these symptoms must be present for a minimum of 6 months
and must signifi cantly impair functioning. - Positive symptoms are delusions, hallucinations, disorganized
speech, and disorganized behavior. However, research fi ndings
suggest that the disorganized symptoms form their own distinct
cluster and should be grouped separately from delusions and
hallucinations. - Negative symptoms are fl at affect, alogia, and avolition.
- Research studies have indicated that cognitive defi cits under-
lie negative and disorganized symptoms of schizophrenia. Such
defi cits include problems with attention, working memory, and
executive functioning. The DSM-IV-TR criteria have been criti-
cized for omitting important cognitive and social defi cits that
lead to positive and negative symptoms and that are closely
associated with prognosis. - DSM-IV-TR distinguishes fi ve subtypes of schizophrenia: para-
noid, disorganized, catatonic, undifferentiated, and residual
schizophrenia. However, because the symptoms of schizophre-
nia often shift over time, an individual’s subtype can change.
Many researchers argue that a more meaningful way to distin-
guish subtypes of schizophrenia would be based on whether
the individual has a defi cit or nondefi cit subtype. - Symptoms of schizophrenia can appear to overlap with those of
other disorders, notably mood disorders and substance- related
disorders. The category of psychotic disorders specifically
requires symptoms of hallucinations or delusions; disorders
in this category are schizophrenia, schizophreniform disorder,
brief psychotic disorder, schizoaffective disorder, delusional
disorder, and shared psychotic disorder. These disorders, along
with schizotypal personality disorder, are part of a spectrum of
schizophrenia-related disorders.- Schizophrenia occurs in approximately 1% of the population
worldwide, and most people with schizophrenia have at least
one comorbid disorder. Men have an earlier onset of the disor-
der than do women. Symptoms of the disorder typically evolve
in phases: premorbid, prodromal, active, and then middle-to-
late phases. - Up to 15% of people with schizophrenia commit suicide. People
with this disorder who behave violently are most likely to have a
comorbid disorder that is associated with violent behavior, such
as a substance-related disorder. People with schizophrenia are
more likely than other people to be victims of violence.
Making a Diagnosis
- Reread Case 12.1 about Emilio, and then determine whether or
not his symptoms met the minimum criteria for a diagnosis of
schizophrenia. Specifi cally, list which criteria apply and which
ones do not. If you would like more information to determine
his diagnosis, what information—specifi cally—would you want,
and in what ways would the information influence your deci-
sion? If you decide that a diagnosis of schizophrenia is appro-
priate for Emilio, do you think he has the defi cit or nondefi cit
subtype, and why?
Understanding Schizophrenia
Despite the low odds that all four of the Genain quads would develop schizo-
phrenia, it did happen. Why? The neuropsychosocial approach helps us to un-
derstand the factors that lead to schizophrenia and how these factors infl uence
each other. As we shall see, although neurological factors (including genes) can
make a person vulnerable to the disorder, psychological and social factors also
contribute to its development—which may help explain not only why all four
Genain quads ended up with schizophrenia, but also why the disorder affected
them differently.
The quads shared the same genes, looked alike, and at least in their early
years, were often treated similarly, especially by Mrs. Genain. However, Hester was
smaller and frailer than the others; she weighed only 3 pounds at birth and could
not always keep up with her sisters. Because of Hester’s diffi culties, it wasn’t always
possible to treat the four girls the same, and so Mr. and Mrs. Genain sometimes
treated them as two pairs of twins: Nora and Myra were paired together (they were
seen as most competent), and Iris—who in fact was almost as competent as Nora
and Myra—was paired with Hester.
Let’s look at the specific neurological, psychological, and social fac-
tors that give rise to schizophrenia and then examine how these factors affect
one another.