HYPERTROPHY OF THE INFERIOR OLIVES IN THE CAT

Abstract

In this paper 2 cases of olivary neuronal hypertrophy in the cat were described. They developed following ablation of the cerebellum, the central nuclei included. In one, in which one half of the cerebellum only was ablated totally and the other only partially, the most extensive distribution of hypertrophic neurons was contralateral to the total ablation. Neuronal hypertrophy as far as could be established presented the same morphological features as in man. Its distribution, in contrast to man, was confined to the medial accessory olive instead of the main olive. It was emphasized that in the cat the majority of the mesencephalic afferents terminate in this nucleus, whereas in man they terminate in the main olive. However, definite connections between definite areas of the cerebellum and the origin of these afferents could not be established. Therefore, in the cat as well as in man olivary neuronal hypertrophy remains to be unexplained with respect to its exact origin.