Figure 1.

Hypotheses on the genesis of phantom limb pain. Simplified schematic of motor (“M”) and somatosensory (“SMS”) signals in a healthy able-bodied, and a person post-amputation. The red arrow resulting in pain perception represents the entire pain neurosignature along with nociceptive fibers where relevant (A–F). For instance, in a healthy subject, the red signal represents nociceptive afferents firing when stimulated (“↯”), as well the neurosignature that results in pain perception (A). The hypotheses of PLP are illustrated in function of changes in efferent and afferent pathways (A–F), as well as their processing circuitry, such as sensorimotor cortical representations (G–F).