The Journal of Neurophysiology Vol. 88 No. 1 July 2002, pp. 300-305
Copyright ©2002 by the American Physiological Society

Cortical Representation of Venous Nociception in Humans

 ¹Department of Neurology and  ²Department of Anesthesiology, Heinrich-Heine-University, 40225 Düsseldorf, Germany

Ploner, Markus, Holger Holthusen, Peter Noetges, and Alfons Schnitzler. Cortical Representation of Venous Nociception in Humans. J. Neurophysiol. 88: 300-305, 2002. Painful sensations can be evoked by application of thermal, mechanical, and chemical stimuli to the blood vessels. The cortical substrates of these sensations are unknown. We therefore used whole-head magnetoencephalography to record cortical responses to painful laser stimuli applied cutaneously and intravenously to the dorsum of the hand in healthy human subjects. Similar to the cutaneous stimuli, venous stimulation nearly simultaneously activated the contralateral primary and the bilateral secondary somatosensory cortices. In the venous stimulation condition, all activation peaks were about 50 ms earlier than in the cutaneous stimulation condition. Locations of responses to both stimuli did not differ. These results show that the afferent volley from the veins reaches the cerebral cortex significantly earlier than that from the skin. This might be due to differences in peripheral conduction velocity. Apart from this, these findings demonstrate that venous nociception shares the cortical representation of cutaneous nociception in human somatosensory cortices. Thus the cortical representation of nociceptive processing from tissues of mesodermal and ectodermal origin appears to be similar.