Neurocircuitry of conditioned inhibition of analgesia: effects of amygdala, dorsal raphe, ventral medullary, and spinal cord lesions on antianalgesia in the rat.
Watkins LR, Wiertelak EP, McGorry M, Martinez J, Schwartz B, Sisk D, Maier SF. Neurocircuitry of conditioned inhibition of analgesia: effects of amygdala, dorsal raphe, ventral medullary, and spinal cord lesions on antianalgesia in the rat. Behav Neurosci. 1998 Apr; 112(2):360-78.