Reorganization of cerebellorubral terminal fields following hemispherectomy in adult cats.

Tritiated amino acids were injected into the right nucleus interpositus of the cerebellum and the projections to the red nucleus were mapped autoradiographically in adult cats with ablation of the left cerebral hemisphere and in intact controls. In intact animals cerebellorubral terminals were found along the entire rostrocaudal extent of only the left red nucleus. The fields occupied a larger area and were apparently more dense toward the middle third of the nucleus. An outstanding change in hemispherectomized cats was a significant expansion of the terminal fields into the dorsal quadrants. Possibilities for morphological reorganization are discussed.