The book summarizes our current understanding of the ultrastructure and synaptic organization of the mesencephalic trigeminal nucleus (MTN) in the cat as well as the neurochemistry of its neuronal population. Particular emphasis is given to the survey of synaptic connections and the possible physiological involvement of MTN inputs in the transmission of proprioceptive information. Using immunocytochemistry and in situ hybridization histochemistry we have identified distinct neuronal, partly chemically coded MTN subpopulations - large glutamatergic and smaller GABAergic neurons. We also show...