By Shannon Brownlee
Copyright, Nov. 11, 1996
U.S. News & World Report
By their appearances, the three little girls sitting quietly in molded plastic chairs in the psychiatric clinic of Texas Children's Hospital in Houston betray nothing of the mayhem they have experienced. No one would know that the night before, two armed men broke into their apartment in a drug-ravaged part of the city. That the children were tied up and the youngest, only 3, was threatened with a gun. Or that the men shot the girls' teenage sister in the head before leaving (she survived).
Yet however calm the girls' appearances, their physiology tells a different story. Their hearts are still racing at more than 100 beats per minute, their blood pressure remains high and, inside their heads, the biological chemicals of fear are changing their brains. "People look at kids who seem so normal after these experiences and say, `All they need is a little love,' " says Bruce Perry, a child psychiatrist at Children's Hospital and at Baylor College of Medicine. But as Perry and other researchers are finding, trauma, neglect and physical and sexual abuse can have severe effects on a child's developing brain.
Tangled chemistry. Once viewed as genetically programmed, the brain is now known to be plastic, an organ molded by both genes and experience throughout life. A single traumatic experience can alter an adult's brain: A horrifying battle, for instance, may induce the flashbacks, depression and hair-trigger response of post-traumatic stress disorder (PTSD). And researchers are finding that abuse and neglect early in life can have even more devastating consequences, tangling both the chemistry and the architecture of children's brains and leaving them at risk for drug abuse, teen pregnancy and psychiatric problems later in life.
Yet the brain's plasticity also holds out the chance that positive experiences--psychotherapy, mentoring, loving relationships--might ameliorate some of the damage. Much remains unknown. But if scientists can understand exactly how trauma harms the brain, they may also learn much about healing broken lives.
Trauma's toll on a child's brain begins with fear. Faced with a threat, the body embarks on a cascade of physiological reactions. Adrenalin surges, setting the heart pounding and blood pressure soaring and readying the muscles for action, a response called "fight or flight." At the same time, a more subtle set of changes, called the stress response, releases the hormone cortisol, which also helps the body respond to danger.
Increasing evidence suggests that in abused or neglected children, this system somehow goes awry, causing a harmful imbalance of cortisol in the brain. In a study of children in Romanian orphanages, for example, Megan Gunnar, a University of Minnesota developmental psychobiologist, is finding that cognitive and developmental delays correlate with irregular cortisol levels.
Gunnar and others believe that excess cortisol leads to damage in a brain region known as the hippocampus, causing memory lapses, anxiety and an inability to control emotional outbursts. Cortisol and other brain chemicals also can alter brain centers that regulate attention, affecting a child's capacity to attend to words on the blackboard instead of a jackhammer banging outside.
Many of the brain abnormalities seen in abused and neglected children are localized in the brain's left hemisphere, where language and logical thought are processed. Martin Teicher, a psychiatrist at McLean Hospital in Belmont, Mass., compared recordings of brain electrical activity in abused and normal children. His finding: In abused kids, the left hemisphere has fewer nerve-cell connections between different areas. The electrical traces also revealed that tiny seizures, similar to those of epileptics, crackled through various sectors of abused children's brains. Children with the most abnormal recordings were the most likely to be self-destructive or aggressive.
Scanning for danger. Abused children also show a variety of other disturbances in physiology, thinking and behavior. Many have elevated resting heart rates, temperature and blood pressure. Hypervigilance is common. Abused kids continually scan their surroundings for danger and overinterpret the actions of others: An innocent playground bump may be seen as a direct threat. And as many as half of children from some violent neighborhoods show symptoms of Attention Deficit Hyperactivity Disorder (ADHD), compared with about 6 percent of the general population.
"Children who are aroused [from fear] can't take in cognitive information," says Perry. "They're too busy watching the teacher for threatening gestures, and not listening to what she's saying." Such behavior makes sense, given the constant threats in the child's world. His brain has become exquisitely tuned to emotional and physical cues from other people. At the same time, he may be failing to develop problem solving and language skills. Perry has found that in a group of neglected children, the cortex, or thinking part of the brain, is 20 percent smaller on average than in a control group.
Studies now indicate that abused and neglected children run a high risk of developing mental illnesses. Since 1987, National Institute of Mental Health child psychiatrist Frank Putnam has tracked 90 sexually abused girls, comparing them to a control group who were not abused. The abused girls were more likely to evidence depression and suicide attempts, and many showed the beginnings of PTSD, including anxiety attacks and abnormal levels of cortisol, which are also seen in combat veterans. Putnam also found a decline in the abused girls' IQ over time. Saddest of all, the abused girls are rated by their teachers as not very likable. "That's tragic," says Putnam, "because the one place where they might find some support is at school."
Indeed, for some children, a loving adult can serve as a powerful antidote to abuse and neglect. Infants and young children normally learn from a comforting caretaker how to soothe themselves, thereby regulating their stress response and cortisol levels. Researchers now believe loving relationships also can help older children reset their response to stress when it has been derailed by abuse. Says Gunnar: "We don't know when the door to the brain's plasticity closes."
Unfortunately, loving damaged children can be tough. One minute they are hostile, the next withdrawn. In class, they escape their feelings by daydreaming. When the teacher confronts them, they retreat even further. Then, says Perry, "the teacher touches the kid. When you touch them, that's incredibly threatening, and the child has a tantrum."
The growing understanding of what's going on in an abused and neglected child's brain has begun to yield new treatments. In addition to psychotherapy, Perry gives some of his young patients clonidine, a drug that helps check the fight-or-flight response. Clonidine, and other drugs that interfere with the release of cortisol, may decrease the chances a child will go on to develop PTSD. Perry also hands out devices that allow teachers and foster parents to monitor a child's heart rate from a distance, so they can refrain from making demands on him when he's frightened.
For every child who finds help at a clinic like Perry's, there are dozens who fall through the cracks. Only a fraction of the millions of children who are mistreated each year receive the kind of help that can reverse the underlying physiological changes they suffer. Ultimately, says McLean's Teicher, failing these kids may be shortsighted. They are less likely to live up to their economic potential, and more likely to wind up in prison, on drugs or in psychiatric units, he says. "The cost on society of having a child who has gone through abuse is enormous."