Marginal shell of the anteroventral cochlear nucleus: acoustically weakly-driven and not-driven units in the unanesthetized decerebrate cat.

The ventral cochlear nucleus (VCN) of the cat is encapsulated by a marginal shell which is anatomically distinct from the central core of the VCN. Physiologically, little is known about the marginal shell. We report here a new finding that the marginal shell of the anteroventral cochlear nucleus (AVCN) in the unanesthetized decerebrate cat contains neural units which were weakly driven or not driven acoustically. The locations of the single units were histologically determined. Our observations also included other neural units of the marginal shell which were strongly driven acoustically; the latter results will be reported separately. The present physiological findings, together with previous anatomical findings of vestibular and somatosensory inputs to the AVCN marginal shell, suggest that some neurons of the AVCN marginal shell receive non-auditory sensory inputs besides weak auditory inputs and that these may play a role in multi-sensory processing.