MEDULLARY SWALLOWING-RELATED NEURONS IN THE ANESTHETIZED CAT

SWALLOWING-RELATED neurons (SRNs) were recorded systematically in the medulla oblongata of urethane-anesthetized cats. The SRNs received ort hodromic inputs from the superior laryngeal nerve (SLN) and showed tra nsient changes in their activity synchronous with swallowing. These ne urons could be divided into three types. Type I SRNs are sensory-relay neurons from the SLN in the nucleus of the tractus solitarius (NTS), type II are interneurons located diffusely in the parvocellular reticu lar formation ventral to the NTS, which received oligosynaptic inputs from the SLN, and type III are motoneurons in the nucleus ambiguus. So me type II neurons still showed the swallowing activity after the anim als were paralysed, which suggests that they could be involved in the generation of swallowing outputs. (C) 1998 Rapid Science Ltd.