The role of hypoglossal sensory feedback during feeding in the marine toad, Bufo marinus.

Research output: Contribution to journalArticle

30 Scopus citations


Behavioral observations demonstrate that bilateral deafferentation of the hypoglossal nerves in the marine toad (Bufo marinus) prevents mouth opening during feeding. In the present study, we used high-speed videography, electromyography (EMG), deafferentation, muscle stimulation, and extracellular recordings from the trigeminal nerve to investigate the mechanism by which sensory feedback from the tongue controls the jaw muscles of toads. Our results show that sensory feedback from the tongue enters the brain through the hypoglossal nerve during normal feeding. This feedback appears to inhibit both tonic and phasic activity of the jaw levators. Hypoglossal feedback apparently functions to coordinate tongue protraction and mouth opening during feeding. Among anurans, the primitive condition is the absence of a highly protrusible tongue and the absence of a hypoglossal sensory feedback system. The hypoglossal feedback system evolved in parallel with the acquisition of a highly protrusible tongue in toads and their relatives.

Original languageEnglish (US)
Pages (from-to)245-252
Number of pages8
JournalJournal of Experimental Zoology
Issue number3
StatePublished - Dec 1 1992


ASJC Scopus subject areas

  • Animal Science and Zoology

Cite this