December 12, 2005

The Maturing Brain and Schizophrenia

The St. Louis Dispatch (newspaper) recently had an excellent story by Tina Hesman and Matthew Franck on how researchers are studying and comparing the development of normal brains, with those that develop mental illness - to better identify the processes as early as possible, and to potentially prevent the brain disorder from developing in the first place. The research is moving ahead and early identification and treatment is showing significant and positive clinical results. Following is an excerpt from the 4-part series:

"To date, much of the discussion around teenagers has focused on why so many change from adorable children into sometimes moody pre-adults. But the latest research has focused on defining normal and tracking the changes that may trigger mental illnesses or strip the defenses of a mind already vulnerable to psychiatric disease. Knowing what's "normal" may lead to a tool that can predict which adolescent is likely to fall prey to depression, bipolar disorder, schizophrenia or a variety of other brain disorders. The key is to figure out who is vulnerable in time to change the course of brain development and head off the disease or reduce the devastation caused by mental illnesses. ...

"For parents worried about their children getting labeled too young, I can sort of see that, because the indicators aren't hard and fast yet," said Dr. Deborah Yurgelun-Todd, director of cognitive neuroimaging at the Brain Imaging Center at McLean Hospital and Harvard Medical School in Boston. "We have hints. We have suggestions of trends that seem to be more typical," but no definitive diagnostic test yet. ...

There is no question that the brains of people with schizophrenia and bipolar disorder look and work differently from those of their healthy peers, Yurgelun-Todd said. And those changes probably start earlier than most people suspect.

Her research into adults with schizophrenia and bipolar disorder showed significant brain changes. Those alterations were already present when schizophrenics had their first episode, and she began tracing the illness to its earliest appearance.

It now seems that some people may be genetically predisposed to develop illness, but the defect does not become apparent until the brain matures, she said. Stress, drugs, and other brain traumas are also known to trigger schizophrenia in people who are genetically predisposed to the disorder.

Dr. Judith L. Rapoport and her colleagues at the National Institute of Mental Health also have been searching for the roots of schizophrenia. For a decade and a half, they have repeatedly scanned the brains of people ranging from toddlers to adults. Along the way, they began to discover how normal brains mature.

Only last year, the group published its first analysis of the maturing human brain in living people. The general layout of the brain doesn't change as people mature, Rapoport said. But the brain grows and shrinks, gets rewired and refined, parts are encased in protective coatings, brain cells die, and sex hormones and neurotransmitters flood in. This all happens under the influence of genetic and environmental blueprints designed to shape the organ into a brain ready for the responsibilities of adulthood.

The timing of the hormonal surges and brain changes with the onset of mental illnesses probably aren't coincidental, researchers say. One theory holds that because brain structures involved in emotion are developing in the teenage years, the brain is more susceptible to emotional disturbance at that time.

Neurochemical systems are also developing during adolescence. Dopamine, a brain chemical that governs pleasure, motivation and interpreting perception, reaches peak production in early to mid-adolescence.

It is also one of the brain chemical systems most affected by schizophrenia. Drug and alcohol abuse or other experiences that affect dopamine may contribute to mental illness during certain sensitive times in the brain maturation process, research suggests.

Understanding normal brain development is crucial to understanding mental illnesses because some of the areas most changed during adolescence are also implicated in schizophrenia, bipolar disorder and other psychiatric disorders. ...

During brain development, the gray and white matter increase in volume, Rapoport said.

White matter growth accelerates in the teen years and continues into adulthood. The "growth" is actually the result of myelin encasing the brain's connecting wires.

The earliest parts of the brain to get wrapped in myelin are the parts that control movement and language -- skills young children need, said Dr. Henry Nasrallah of the University of Cincinnati College of Medicine. But some parts of the brain don't really come online until the teen years, he said.

Among the last areas to become fully wired are the frontal lobes and temporal lobes. Those parts of the brain are significant because they control abstract thinking, impulsiveness and emotion. ...

The research into the development of the brain during adolescence is beginning to show how the brains of mentally ill people are different.

Dr. Melissa P. DelBello, co-director of the Bipolar Disorders Research Program at the University of Cincinnati, and her colleagues have been peering into the white matter of the brain. In teenagers with bipolar disorder, the white matter is disorganized, particularly in the frontal regions, the researchers found.

Since those regions govern impulse control and attention, and help regulate emotion, disruptions there can produce erratic behavior.

While the white matter is being wrapped in its protective coating, the gray matter of the brain is undergoing its own changes. Inefficient or confusing connections between neurons, called synapses, are pruned and some cells die.

From the ages of about 14 through 16, people lose about 20 percent of the synapses in the brain, Nasrallah said.

This loss of gray matter, he said, is "like a company laying off 10 percent of its workers and still being profitable and efficient."

The pruning may actually help the brain work better, not harder. ...

Rapoport's studies showed that children with early-onset schizophrenia rapidly lose gray matter from the frontal and temporal lobes, and they lose more gray matter than their healthy peers.

The pattern looks like a great exaggeration of normal maturation, Rapoport said.

"It's way out of whack and happens much too fast," she said.

But the way to slow the process is unclear. It could involve medicating children who display warning signs of schizophrenia but don't yet have the illness.

Yurgelun-Todd said, "We have no problems taking aspirin to prevent heart disease or vitamins to prevent colds, so if you know you're going to get a devastating brain disease, maybe it's not so bad to take a drug."

And drugs may not even be necessary to head off mental illness, she said. Simple changes in the way children are raised could be as effective.

"The human brain is very susceptible to its environment, both positive and negative," she said.

Some people think censoring movies, TV and video games could help promote mental health in youngsters. But it may be more important that families provide stimulating activities, good role models and a supportive environment for their children, Yurgelun-Todd said.

We encourage you to read the full story here: Knowing What's Normal


well i have been using hashish and and alcohol it was my biggest mistake i had ever done in my life when i was teen ..i was diagnosed schozophrenia after having break up with my gf ... i wish that armed forces of usa and other countries work to stop street drugs from world

Posted by: khan at June 26, 2007 08:27 AM

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