Changes in somatosensory evoked potentials and reflectory reactions of human hand muscles to nociceptive stimulation of index finger before and during ischemia

Abstract

Somatosensory evoked potentials and reflectory reaction of m. thenar to nociceptive electrical stimulation of the index finger before and during its ischemia were studied in healthy volunteers. The amplitude of early components of the somatosensory evoked potentials N23-P31 and N50-P120 correlated with stimulus intensity, while the amplitude of N140-P200 did not depend on both stimulus intensity and pain. The nociceptive RIII reflex recorded from m. thenar was the most reliable index of pain caused by electrical stimulation of the finger.