Conditioned pain modulation (CPM)

Conditioned pain modulation (CPM) refers to a psychophysical paradigm and neurophysiological process in which the perception of one painful stimulus is reduced (inhibited) by the application of a second, remote painful stimulus. It reflects the net effect of endogenous descending pain inhibitory systems, primarily involving the brainstem and spinal cord, and is often tested using methods in which a "conditioning" stimulus modulates the pain from a "test" stimulus delivered elsewhere on the body[1][2][3][4][7][10]. CPM is considered analogous in humans to animal phenomena known as diffuse noxious inhibitory control (DNIC). Deficient CPM response is associated with increased susceptibility to chronic pain conditions and may serve as a phenotypic biomarker for pain risk and treatment selection, but it is not a molecule, receptor, or direct pharmacological target. In summary: Conditioned pain modulation is a functional *system-level process* in the nervous system, not a classical molecular or receptor target. It serves as a biomarker in pain research and clinical risk stratification, rather than a druggable entity or direct target of pharmacotherapy[1][3][4][7][10].

Other names

Diffuse noxious inhibitory control (DNIC)Heterotopic noxious conditioning stimulation (HNCS)Endogenous analgesia