[Somatosensory evoked potentials to median nerve stimulation in normal children].

Short latency somatosensory evoked potentials to median nerve stimulation (MN-SSEP) were studied in 292 normal children of 1 month to 14 years old and in 34 adults. We divided these normal children into 7 groups, each group containing about 40 children. Evoked potentials were recorded at 3 levels: Erb's point, seventh cervical vertebra, and contralateral parietal scalp. N 9, N 13 and N 20 wave forms were recorded in all the children, except that in some children under 2 months of age the N 20 component was absent on one side (7.3%). The mean latency of N 9 N 13 and N 20 decreased with age until they reached 1 year and 3-5 years of age respectively, and then it increased with age. The interpeak latency of N 13-N 20 decreased steadily with age, becoming close to the value of adults at about 8 years of age. There was no significant sex difference in interpeak latencies, but the difference was significant in absolute peak latencies. In this paper are proposed the normal referential values of MN-SSEP in children.