During the forthcoming year two main projects are to be worked on: A. The synaptic contacts made by cells of the substantia gelatinosa of the spinal cord are to be further characterized by a method which has been developed in this laboratory. Degenerating axonal terminations of gelatinosa cells have been demonstrated in both the marginal and gelatinosa areas using electromicroscopic techniques. Further studies will include nucleus proprius neurons. B. Firing patterns of multiple neurons in the spinal nucleus of the trigerminal in response to quantitated stimuli of the face will be studied using microelectrode techniques, window discriminators and computerized print-out of discharge patterns stored on tape.