Agenesis of the corpus callosum is not a disease or an illness. Instead, it is a brain abnormality that prevents the left and right halves of the brain from communicating with each other. The corpus callosum is the largest connective pathway in the human brain, with some 200 million nerve fibers joining in the middle. Its function is to connect the two halves, or hemispheres, of the brain. It also helps coordinate signals between different parts of the brain, and it aids in our thinking processes. In agenesis of the corpus callosum, or ACC, the hemispheres are isolated from each other. This can occur as an isolated brain problem, in conjunction with other brain abnormalities, or as part of a problem that involves many parts of the body.
The cause of agenesis of the corpus callosum is the disruption in the development of the brain while the fetus is still growing. This may be due to chromosomal or genetic errors, a prenatal infection, or any other factor that would disrupt the prenatal environment. It is not usually possible to determine the precise cause of ACC.
The characteristics of a child with ACC cover a wide range. This includes delays in milestones such as walking or talking, poor motor coordination and depth perception, and low muscle tone. Also, there can be malformations causing midline facial defects as well as deficient skills requiring matching of visual patterns. The degree of disability may range from mild to severe. Most ACC children have average intelligence with mild learning disorders, allowing them to lead normal, independent lives. Severe handicaps can include cerebral palsy, mental retardation, autism and seizure disorders.
There is no cure for ACC, and the best course of treatment is management of symptoms through speech, physical and occupational therapy. In the teenage years, most children will show increased progress in abstract reasoning, problem-solving and social skills. Though he may have kept up with his peers previously, at this point the ACC child may fall behind. Symptoms are more evident as he becomes an adolescent and young adult, though the condition is stable and does not worsen with age.
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Agenesis of the Corpus Callosum Information Page. (n.d.). Retrieved July 2009, from National Institute of Neurologic Disorders and Stroke: http://www.ninds.nih.gov/disorders/agenesis/agenesis.htm
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