March/April 2001Vol. 2, No. 2Abuse Can Permanently "Rewire" Children's Brains

Physical scars may heal, but abuse leaves an indelible impression upon children's developing brains, according to investigators at the McLean Hospital in Belmont, Massachusetts.

Physical, psychological, or sexual abuse can "rewire" the developing brain during childhood, and these changes eventually may cause disorders such as anxiety and depression to surface in adulthood. "The science shows that childhood maltreatment may produce changes in both brain function and structure," said lead investigator Dr. Martin Teicher. His team found that the following four types of abnormalities were more likely to be present in child abuse and neglect victims:

• Changes to the limbic system--the part of the brain that controls emotions--resulting in epileptic seizures and abnormal electroencephalograms (EEG), usually affecting the left hemisphere of the brain, which is associated with more self-destructive behavior and more aggression.
• Deficient development of the left side of the brain, which may contribute to depression and impaired memory.
• Impaired corpus callosum--the pathway integrating the two hemispheres of the brain--resulting in dramatic shifts in mood and personality, especially with boys who suffered neglect and sexually abused girls.
• Increased blood flow in the cerebellar vermis--the part of the brain involved in emotion, attention, and regulation of the limbic system--disrupting emotional balance.

In reviewing animal studies that showed that neglect and emotional trauma trigger changes in hormones and neurotransmitters in parts of the brain that regulate fear and anxiety, the research team speculated that the same process occurs in child victims. "We know that an animal exposed to stress and neglect early in life develops a brain that is wired to experience fear, anxiety and stress," Teicher said. "We think the same is true of people."

For example, post-traumatic stress disorder (PTSD) is one of several psychiatric disorders that may be fueled by childhood trauma. Usually associated with combat veterans, PTSD victims continually relive a traumatic event in dreams and in waking life.

Teicher and his colleagues hope their findings about childhood abuse's impact on the brain will lead to new ideas for treatment and better efforts at prevention. "Childhood abuse isn't something you 'get over,'" Teicher observes.

The study is published in the Fall 2000 issue of Cerebrum (http://www.dana.org/books/press/cerebrum).

The McLean Hospital press release on this study is available online at: http://www.mcleanhospital.org/PublicAffairs/ 20001214_child_abuse.htm.