(Clozaril) are both dopamine and serotonin antago-
nists. Drug studies have shown that clozapine can
dramatically reduce psychotic symptoms and ame-
liorate the negative signs of schizophrenia (Marder,
2000; O’Connor, 1998).
Researchers also are exploring the possibility
that schizophrenia may have three separate symptom
complexes or syndromes: hallucinations/delusions;
disorganization of thought and behavior; and negative
symptoms (Arango, Kirkpatrick, & Buchanan, 2000).
Investigations show that the three syndromes relate
to neurobiologic differences in the brain. It is postu-
lated that schizophrenia has [these three] subgroups,
which may be homogeneous relative to course, patho-
physiology, and, therefore, treatment.
IMMUNOVIROLOGIC FACTORS
Popular theories have emerged that exposure to a
virus or the body’s immune response to a virus could
alter the brain physiology of people with schizo-
phrenia. Although scientists continue to study these
possibilities, few findings have validated them.
Cytokines are chemical messengers between im-
mune cells, mediating inflammatory and immune
responses. Specific cytokines also play a role in signal-
ing the brain to produce behavioral and neurochemical
changes needed in the face of physical or psychological
stress to maintain homeostasis. It is believed that
cytokines may have a role in the development of major
psychiatric disorders such as schizophrenia (Kronfol
& Remick, 2000).
Recently researchers have been focusing on in-
fections in pregnant women as a possible origin for
schizophrenia. Waves of schizophrenia in England,
Wales, Denmark, Finland, and other countries have
occurred a generation after influenza epidemics. A
study published in the New England Journal of Med-
icinereported higher rates of schizophrenia among
children born in crowded areas in cold weather, con-
ditions that are hospitable to respiratory ailments
(Mortensen et al., 1999).14 SCHIZOPHRENIA 301
Figure 14-1.Scan 11.PET scan with 18F-deoxyglucose shows metabolic activity in a
horizontal section of the brain in a control subject (left) and in an unmedicated patient
with schizophrenia (right). Red and yellow indicate areas of high metabolic activity in
the cortex; green and blue indicate lower activity in the white matter areas of the
brain. The frontal lobe is magnified to show reduced frontal activity in the prefrontal
cortex of the patient with schizophrenia. (Courtesy of Monte S. Buchsbaum, MD,
The Mount Sinai Medical Center and School of Medicine, New York, New York.)