CONVERGENCE OF NOCICEPTIVE AND NONNOCICEPTIVE INPUT ONTO THE MEDULLARY DORSAL HORN IN MAN

Citation
J. Ellrich et al., CONVERGENCE OF NOCICEPTIVE AND NONNOCICEPTIVE INPUT ONTO THE MEDULLARY DORSAL HORN IN MAN, NeuroReport, 9(14), 1998, pp. 3213-3217
Citations number
25
Categorie Soggetti
Neurosciences
Journal title
ISSN journal
09594965
Volume
9
Issue
14
Year of publication
1998
Pages
3213 - 3217
Database
ISI
SICI code
0959-4965(1998)9:14<3213:CONANI>2.0.ZU;2-D
Abstract
REFERRED pain arising in orofacial pain states is probably due to conv ergence of different somatosensory input onto the medullary dorsal hor n (MDH). To examine convergence between nociceptive and nonnociceptive input onto the MDH, the blink reflex (BR) was applied. R1- and R2-com ponents can be evoked by innocuous stimuli, but only the R2 is elicite d by painful heat. The BR was elicited by innocuous electrical stimuli applied to the supraorbital nerve. A conditioning painful heat pulse which did not evoke any BR was homotopically applied to the left foreh ead preceding the electrical stimulus by 75 ms. While R1 remained unch anged, the R2 was facilitated by about 30%. This study demonstrates a convergence of low-threshold mechanoreceptive and nociceptive inputs o nto interneurons of the MDH in man. (C) 1998 Lippincott Williams & Wil kins.