Moreover, simply snipping a pair of cranial nerves could quickly render someone blind, deaf, or anosmic—the pathways are relatively simple, discrete, and well characterized. Pain is processed redundantly and diffusely, and there is simply no surgical intervention to relieve chronic pain (as many medical doctors and their patients know too well). Instead, pain recruits overlapping pathways and circuits throughout the body and brain and, along with a rich neurochemistry of opioids and anti-opiates, portends the critical nature of pain for our survival.
