Forming a brain
Under the old thinking, the adolescent brain was fully formed, needing only to be filled with facts and experiences to become an adult mind.
At the same time, many people rejected the idea that young people were even capable of developing mental illnesses.
"You couldn't even get the diagnosis until about the mid-[19]80s," said Dr. Kelly N. Botteron, an assistant professor of child psychiatry at Washington University in St. Louis. "Earlier child psychiatrists thought kids were not even cognitively capable of getting depressed."
The new research shows a teenage brain as an organ in transition with a volatile and vulnerable composition. "It's not entirely clear that the brain is ever finished developing," said Dr. John Csernansky, director of the Conte Center for the Neuroscience of Mental Disorders at Washington University.
The evolving teen brain clearly isn't adultlike until the early 20s. So the old stereotypes may have some merit.
If teens act "young and stupid," it may be because brain areas that dampen impulsivity and govern rational thought are among the last to mature.
All that is fine when the brain develops normally.
But what's shaking up those involved with mental health is what happens when the teen brain fails to successfully reinvent itself as an adult brain. Researchers increasingly believe if that process misfires, teens are vulnerable to developing mental illness.
In fact, many now believe that several severe mental illnesses have roots in the developing teen brain. That's true even if symptoms aren't seen until years or decades later.
What concerns many is the possibility that early warning signs might be disregarded, as parents, educators and others ignore what looks to them like typical teen behavior.
Early identification matters because treating the disorders early could head off the worst manifestations of the diseases.
"If an adult gets depressed and loses a year of function, they can generally get back close to where they were, but if a kid loses a year, it's really hard to catch up again in terms of development," Botteron said.
The implications of the research are vital in an age when society is increasingly aware of the consequences of abnormal and violent teen behavior.
While no one can say for certain whether school shootings like the one at Columbine High School in Colorado in 1999 are the result of mental illness, few question that early detection would reduce violent acts by teens.
Sometimes mental illness is to blame when children disrupt class or get into fights at school. Some may turn to drug and alcohol use to help ease the pain, leading to run-ins with the law.
Perhaps the chief hope of the new research is that it could someday mean the difference between life and death for teenagers suffering from bipolar disorder (often called manic depression), schizophrenia and major depression.
Each of those disorders can lead to suicide, which for years has ranked as the second- or third-leading cause of death for teens.
Coalition of critics
Leading the fight against teen mental-health screening is a coalition of critics that has made allies of Scientologists like Tom Cruise and conservatives like Phyllis Schlafly.
Much of their opposition is based on religious grounds. Some question whether mental illness even exists. Other parents fear that a child they view as normal will be incorrectly labeled as mentally ill.
But a greater share of the resistance roots from a skepticism over whether mental illness in youth can even be accurately diagnosed, much less treated. Those doubts increase as more children are medicated for behavior problems.
Mental-health professionals say there's some validity to the criticism. They point to a system that tolerates hasty diagnoses, often by physicians with no mental-health expertise.
In short, they admit that at the very least, the field of adolescent mental health suffers from a crisis of credibility — one that scientific research may be unable to address.
Much of the skepticism of mental illness and its diagnosis is grounded in the fact that doctors have no blood tests, brain scans or chemical analysis from which to base their conclusion.
"You can't examine somebody's thoughts like you can X-ray their insides," said Dr. Anne Glowinsky, a psychiatrist at Washington University. "When somebody comes to the ER and says 'I'm suicidal,' we don't have a test [to confirm] that."
No such tools exist because the brain hasn't given up its secrets easily.
Most of what scientists know about how mental illness affects the brain comes from examinations of dead people. Until recently, scientists couldn't peer into living brains to look for changes associated with normal development or the ravages of disease. That is beginning to change, as researchers develop ever-more sensitive brain scanners.
Views into brain
In the past several years research groups have published composite pictures of healthy brains and those affected by mental illness. The differences between the healthy group and people with depression, schizophrenia and bipolar disorder appear striking, but don't distinguish between causes of psychiatric disorders and the consequences of having a mental illness.
And the composite pictures are somewhat misleading. They present the most clear-cut findings from studies of dozens to hundreds of brains. But a snapshot of an individual brain may fall somewhere between "normal" and mentally ill.
Consequently, scientists still can't scan an individual and say with certainty that the person does or does not have a mental illness based upon the structure or function of the brain.
But new efforts to define normal, healthy development and to track brain changes associated with mental illness may lead to predictive tests that could show which children are at risk of getting a psychiatric disease.
But a brain scan for mental health as reliable as a mammogram or colonoscopy is probably decades away, scientists say. For now, psychiatrists and psychologists must still rely on interviews and observations of children's behavior to diagnose mental illness.
|
