Maria Adele Giamberardino1. 1. Pathophysiology of Pain Laboratory, Ce.S.I., "G. D'Annunzio" Foundation, Department of Medicine and Science of Aging, "G. D'Annunzio" University of Chieti, via Colle del'Ara, 66013 Chieti Scalo (Chieti), Italy. mag@unich.it