The median nerve SEP in preterm neonates: a study of maturation.

We studied the right and left median nerve somatosensory evoked potential in a group of preterm neonates at birth (36 weeks) and at 37 and 38 weeks conceptional age. The latency of SEP at Erb's point did not differ from one examination to the next but the latency of cortical wave N1 in the second and third examinations was statistically shorter that of the first. The ascending slope of N1 decreased in duration like the latency of N1. We discuss our results in the light of published work and stress the value of SEP as a noninvasive method of assessing maturational deficits in the somatosensory circuits.