Coordinated control of the tongue during suckling-like activity and respiration

Abstract

The tongue can move freely and is important in oral motor functions. Tongue movement must be coordinated with movement of the hyoid, mandible, and pharyngeal wall, to which it is attached. Our previous study using isolated brainstem-spinal cord preparations showed that application of N-methyl-D-aspartate induces rhythmic activity in the hypoglossal nerve that is coincident with rhythmic activity in the ipsilateral trigeminal motor nerve. Partial or complete midline transection of the preparation only abolishes activity in the trigeminal motor nerve; therefore, the neuronal network contributing to coordinated activity of the jaw/tongue muscles is located on both sides of the preparation and sends motor commands to contralateral trigeminal motoneurons. Arterially perfused decerebrate rat preparations exhibit stable inspiratory activity in the phrenic nerve, with efferent nerves innervating the upper airway muscles (the hypoglossal nerve, a branch of the cervical spinal nerve, the external branch of the superior laryngeal nerve, and the recurrent laryngeal nerve) under normocapnic conditions (5% CO). During hypercapnia (8% CO), pre-inspiratory discharges appear in all nerves innervating upper airway muscles. Such coordinated activity in the pre-inspiratory phase contributes to dilation of the upper airway and improves hypercapnia.

Reliability and Responsiveness of a Novel Device to Evaluate Tongue Force

“…The tongue is a muscle that is part of the stomatognathic system and plays an important role in phonation, breathing, and eating [1,2]. The tongue has been classified as a muscular hydrostat structure due to its ability of movement and deformation without Life 2023, 13, 1192 2 of 13 a bone holder preserving its volume [2].…”

Mafa-dependent GABAergic activity promotes mouse neonatal apneas

“…Active interruption of the respiratory airflow is essential in a number of neonatal behaviors, for example to direct milk toward the alimentary tract 7 , to protect airways from the inhalation of dust or irritant chemicals 8 , or to increase subglottal pressure before uttering a sound 9 . When their duration extends beyond the point at which blood oxyhemoglobin de-saturates, respiratory pauses can be life threatening.…”