matched normal subjects. All absolute and interpeak latencies except for the interpeak latency IV-V were shorter in the patients with DS than in normal subjects. The amplitude of wave V and the amplitude ratio of V/I were smaller in patients than in normal subjects. Short latencies in patients were considered to be due to the smaller size of the brain-stem or to faster conduction velocity. The prolonged interpeak latency IV-V and smaller wave V may indicate physiological dysfunctions between the upper pons and lower midbrain. (National DS Society)Forty to forty-five percent of children with Down syndrome have congenital heart disease. Thirty three percent of these are endocardial cushion defects, and the remainder are verntricular septal defects. Tetralogy of Fallot and atrial septal defects also occur. (Epstein, 58) Malformations of the gastrointestinal tract, including intestinal atresia and iperforate anus, occur in about five to ten percent of patients, and there is a reported increased incidence of Hirschsprung's disease, as well as a higher incidence of gastro-esophogeal reflux. (Epstein, 58)Seizure activity is also a risk although if you look at the population of all children with mental retardation, there is a very large number (from 20 to 40%) that have epilepsy. The number is quite lower in DS, but it's still a larger number than in the general population. Studies in the last two decades have estimated the number of people with DS who have seizures to be from 5 to 10%. (Epstein 56)There appears to be two "peaks" in ages at which the onset of epilepsy is more common in DS. The first peak occurs in the first two years of life. The type of seizure most often seen in this age range is the "infantile spasm." This type of seizure involves what looks like a spasm of the body, lasting a few seconds, and sometimes not affecting the infant's state of consciousness. It can also look like a quick drop of the head and/or shoulders if the ...
