Short latency mechanically evoked peripheral nerve and somatosensory potentials in newborn infants

Mechanically evoked short-latency potentials were recorded from ten newborn infants ranging in gestational age from 36 to 42 wk and from a 3-month-old infant during natural sleep. Potentials were recorded from four electrode configurations: (1) over the peripheral nerve at the wrist: distal-proximal; (2) over the peripheral nerve at the axilla-deltoid insertion; (3) over the cervical spinal cord and cerebrum: CII-Fpz; and (4) over the cerebrum: C4-Fpz. All subjects produced clear potentials from configurations 1, 2 and 3. Configuration 4 produced reliable potentials only in one newborn who was large for gestational age (42 wk) and the 3-month-old infant. Average peripheral nerve conduction velocities were 26 m/sec from wrist to axilla and 29 m/sec from axilla to neck. No significant correlation was found between conceptional age and nerve conduction velocity. The application of this technique could allow lesion localization in peripheral as well as central portions of the somatosensory pathway of newborns.