Interaction between licking and swallowing in the drinking rat

Licking behavior of rats appeared to be interrupted periodically for about 20 ms. Behavioral and electrophysiological evidence is presented which indicates that during this period swallowing occurs. The hypothesis was tested that swallowing initiation depends on the volume of water that has accumulated in the oral cavity during drinking. No support for this hypothesis was obtained when the flow rate of water through the drinking tube was manipulated. Alternative hypotheses are discussed.