Trigeminal nerve and eatng in the pigeon (Columba livia): Neurosensory control of the consummatory responses.

Abstract

Electrophysiological, neurobehavioral and cinematographic techniques were used to study the role of the trigeminal nerve in the neurosensory control of eating. Analysis of single-unit data recorded in the pigeon''s trigeminal ganglion indicated that the trigeminal nerve provides somatosensory inputs from the oral region that signal the location and movement of food and monitor the extent of mouth opening. Trigeminal deafferentation, although it did not affect pecking or swallowing, severely impaired the efficiency of eating. Cinematographic analysis showed that the impairment was due to disruption of the neurosensory control of mandibulation-the process by which grain is grasped at the beak tip and moved to the back of the mouth.