Mechanisms of central pain

Central pain is common in patients with stroke, multiple sclerosis, syringo myelia, and spinal cord injury. It frequently develops after a delay of wee ks or months, is associated with sensory change involving the spinothalamic pathways, and has a poor prognosis for spontaneous remission. Hypotheses t o explain the varied clinical manifestations can be divided in two categori es: those stressing aberrant neural activity in the deafferented circuits a nd those focusing on the postlesion imbalance between facilitatory and inhi bitory neural pathways. All models inherently assume a degree of specializa tion of cerebral structures in pain processing, which has not been proved c onclusively.