Ross Lab

Spatial Contrast Theory (old)

The Spatial Contrast Theory of pain and itch proposes that the individual activation of nociceptors contrasts versus activation of larger, overlapping nociceptor populations. Limited nociceptor activation is assumed to correspond to itch and contrasts this stimulus against the largely silent nociceptors of the surrounding nerve fiber receptive field (Namer and Reeh, 2013) Likewise, the activation of several nociceptors by a more robust stimulus results in a pain response.

spatialcontrast

References:
Namer, B. and Reeh, P. (2013) Scratching an itch. Nat Neurosci.16, 117–118