Think of how rattled you might be if you lived in constant fear of a gun going off. Then imagine you are only six or seven years old and trying to do your homework. This is the reality for many children living in America's inner−city neighborhoods today.

It is not news that many inner−city children are exposed to violence. What is less well known is exactly what long−term effects this is having on the rest of their lives. That was the subject of a recent study that followed a group of Philadelphia children for seven years. It found that the negative effects of stress on learning, memory, and overall cognitive development are far more pervasive and longer−lasting than many realize.

By age seven, 74 percent of the children in the study had heard gunfire and 13 percent had witnessed a shooting or stabbing in their own home.

Douglas Bremner, M.D., an expert on stress and its effects on the human brain at Yale, called this "an important study which underlines the role of violence and traumatic stress in the cognitive development of children. It adds to the growing literature which supports the idea that traumatic stressors have an adverse effect on learning, memory and cognitive development." The Philadelphia study corroborates the results of much of Dr. Bremner's ground−breaking work, which has shown that people who undergo extreme stress may suffer actual physical damage to parts of the brain involved in learning and memory.

The author of the Philadelphia study, Hallam Hurt, M.D., Chair of the Neonatology Division at Albert Einstein Medical Center (Philadelphia), followed 113 inner−city children from birth until they were seven years old.

Dr. Hurt's data paints a disturbing picture. By age seven, 74 percent of the children in the study had heard gunfire and 13 percent had witnessed a shooting or stabbing in their own home. 60 percent reported that they worry some or much of the time that they may get killed or die; 20 percent sometimes wished that they were dead; 19 percent had seen a dead body outside their homes.

Even more alarming, children exposed to violence suffered from a variety of personal problems and performed poorly in school.

"This fits," according to Dr. Bremner, "into the context of a range of studies — both in animals and humans — showing that stress can have a negative effect on brain systems involved in memory. This kind of damage may well underlie difficulties with new learning and cognition that cause poor academic performance in these children." It may also mean that helping these children lead better lives may not be as simple as removing them from the stressful environment.

Dr. Hurt's researchers first attempted to evaluate a child's distress level through a series of interviews. For example, a psychologist asked each child about the details of his or her life experiences. If the child mentioned a traumatic event, such as witnessing a drug deal, the psychologist then followed up with more questions about that event. If necessary, children were referred for counseling.

Another test gauged the child's emotional reactions to the violence he or she has experienced. Finally, the child's academic performance was evaluated using school reports and a so−called Culture−Free Self−Esteem Inventory was used to measured self−esteem. Parents and teachers assisted in evaluating the child's behavior.

Using all of this information, each child was categorized as having high or low exposure to violence.

Researchers found that the high exposure group had lower grade point averages, was more often absent from school, had lower self−esteem, and was far more likely to suffer from depression or anxiety.

"For children growing up in poverty," Hurt observed, "violence is almost an everyday occurrence — whether they hear a gun shot or they observe a brutal act. While the media tends to focus on major events related to violence, such as school shootings, there are countless young children going to school everyday with heavy burdens from exposure to violence."

Reviewed by: Doug Bremner, M.D.