Facilitation of late Somatosensory evoked potentials by electrical train stimuli

Somatosensory evoked potentials (SSEP) may reflect synaptic events and could be suitable to characterise the short-time plasticity of synaptic potentials (SP). For this purpose, the left superficial radial nerve was stimulated in 9subjects with single or trains of 3 stimuli (C4' against Fz, time interval 500 ms, 1 Hz or 0.4 Hz). The within train interstimulus intervals (ISI) were varied from 2 to 10 ms. N20, N1 and N2 displayed a significant gain in amplitude following train stimuli compared with single stimuli. Short ISIsof 2 – 4 ms led to higher amplitudes of N20, N1 and N2 compared with longer ISIsof 7 – 10 m…