Fig. 1.

Photomicrographs showing the effects of long-standing unilateral rhizotomies on the spinal cord and dorsal column nuclei. A, Cross section of the first cervical segment of the spinal cord, stained for parvalbumin immunoreactivity (PARV.), from a monkey that survived for 14.3 years after rhizotomy. The cuneate fasciculus (CF) on the operated side (left) is greatly shrunken, and there is displacement of the gracile fasciculi (GF) to theleft. B, Cross section at the spinomedullary junction, stained immunocytochemically for microtubule-associated protein 2 (MAP2), from an animal that survived for 14.3 years after rhizotomy, showing reduction in size of the cuneate fasciculus (CF) on the operated (left) side.