Shannon Brownlee writes in a U.S. News and World Report article, dated Nov. 3, 1996:
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.
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