Viscerocardiac reflexes of the snail.

The viscerocardiac and cardiocardiac reflexes in the snail are effectuated by just two inhibitory motoneurons of the visceral ganglion. The neurons are switched on in parallel and have extensive, partially overlapping receptive fields. Due to the high degree of sensitivity of the nerve endings of these cells to mechanical stimuli, the inhibitory motoneurons of the heart perform an afferent function at the same time. A morphological analysis of the inhibitory neurons demonstrated their identity to the previously identified V21 multimodal interneuron.