RSNA News Release
Faulty Wiring in the Brain May Cause Early-Onset Schizophrenia
Released: December 2, 2003
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At A Glance
Adolescents with early-onset schizophrenia show abnormalities in the white matter of the frontal lobe of the brain.Diffusion tensor imaging (DTI) can identify damage in the white-matter fiber tracts.In patients with early-onset schizophrenia, the cells that control information transmission are defective.
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CHICAGO — Using diffusion tensor imaging (DTI) to look into the brains
of children with schizophrenia, researchers have discovered abnormalities in
the white matter of the frontal lobe that disrupt the transmission of signals
regulating behavior, according to a study presented today at the 89th Scientific
Assembly and Annual Meeting of the Radiological Society of North America (RSNA).
"Until now there's been no sophisticated method of finding abnormalities
in the white matter of the brain," said the study's lead author Manzar
Ashtari, Ph.D., associate professor of radiology and psychiatry at North Shore
Long Island Jewish Health System and Albert Einstein College of Medicine in
New York. "Conventional magnetic resonance (MR) imaging is limited in its
ability to reveal brain myelination, but DTI enables us to measure the myelination
process."
Myelin is the covering of nerve bundles that protects neurons and increases
their transmission efficiency. The accumulation of myelin around these neurons
is called myelination. In the human developmental process, myelination correlates
with maturing patterns of behavior. In patients with schizophrenia, the cells
that carry out the process of myelination are defective.
Myelination activity is at its strongest during the teen years. "This
is a critical time for adolescents who are still maturing emotionally,"
Dr. Ashtari said. "During the myelination process, microstructural damage
to developing white matter fiber tracts may lead to developmental abnormalities.
These are the types of abnormalities we observed in the frontal white matter
regions in the children with schizophrenia."
Dr. Ashtari and her team used DTI to study 12 adolescents with early-onset
schizophrenia and nine healthy, age-matched adolescents. They found distinct
differences in the white brain matter of the frontal lobe, which controls numerous
emotional, cognitive and linguistic behaviors. When signals are disrupted, abnormal
behaviors result. "It's a problem with connectivity," Dr. Ashtari
said. "It's like the wiring in a house, only we are looking at the network
of the brain — how the brain is wired."
Schizophrenia is a chronic and extremely disabling brain disease that affects
one out of every 100 people in the United States. There is no cure.
According to Sanjiv Kumra, M.D., co-author of the study and research scientist
at Zucker Hillside Hospital in New York, adolescents are diagnosed with schizophrenia
if they meet two of the five criteria — hallucinations, delusions, thought
disorder, bizarre behavior and negative symptoms (lack of motivation, loss of
enjoyment in activities) — for at least six months and display deterioration
of functioning. Children with schizophrenia are likely to exhibit developmental
delay and language and emotional problems before the onset of psychotic symptoms.
DTI can identify white matter abnormalities before major symptoms are apparent.
"Our goal is to detect and treat this disease early, so we can stop the
progression before full-fledged symptoms develop," Dr. Ashtari said.
"Early-onset schizophrenia is especially disheartening because so many
of these teens aren't diagnosed until they're adults," Dr. Kumra said.
"Because these patients develop the disease at an early age when they have
not yet built their lives, they tend to have a worse prognosis than those who
have adult-onset schizophrenia."
Dr. Ashtari hopes that further DTI studies will yield more insight into the
inner workings of schizophrenia. "If the malformation in the myelination
process is the cause of schizophrenia, future special efforts can be focused
in production of therapeutic agents that speed up or restart the myelination
process," she said.
Co-authoring the study with Drs. Ashtari and Kumra are Marjorie McMeniman, Ph.
D., Joshua Vogel, Alan Sloan Diamond, M.D., and Philip Szeszko, Ph.D.
RSNA is an association of more than 35,000 radiologists, radiation oncologists
and related scientists committed to promoting excellence in radiology through
education and by fostering research, with the ultimate goal of improving patient
care. The Society is based in Oak Brook, Ill.
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