Somatosensory event-related potentials evoked by painful and non-painful electrical stimuli

The aim of this study is to compare thr somatosensory evwnt-related potentials (SERPs) elicited by painful and non-painful electrical stimuli, and to investigate the central processing of nociceptive input from skin. The thumb and index fingers of the right hand were stimulated. The index finger stimuli (80%of the total stimulus number) which were target stimuli were derivered at random. SEPRs were recorded from 5 sthere was no calp sites. The latency and amplitude of each SEPR component were analyzed mainly in terms of N140 and P300. Furthermore, topographical maps and dipole localization maps of SERPs were also produced. Our results revealed that the amplitudes of the N140 and P300 components were larger and the latency of the P300 component shorter in SERPs elicited by painful stimuli. However, significant difference in the topographical distribution of the N140 and P300 components and the dipole location of the P300 component between painful and non-painful stimuli. These findings may suggest that painful sensations and non-painful sensations are generated through similar cortical pathways, and that the velocity and intensity of cognitive cerebral processing of the sensations faster and stronger in painful atimuli.

event-related potential

somatosensory

pain

dipole

topography