Affiliations: [a] Department of Otolaryngology, University of Pittsburgh, Pittsburgh, PA 15213, USA | [b] Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 12260, USA | [c] Department of Otolaryngology, University of Colorado Health Sciences Center, Denver, CO 80262, USA
Correspondence:
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Corresponding author: Dr. Bill Yates, Department of Otolaryngology, University of Pittsburgh, Eye and Ear Institute, Room 106, 203 Lothrop Street, Pittsburgh, PA 15213, USA. Tel.: +1 412 647 9614; Fax: +1 412 647 0108; E-mail: byates@pitt.edu
Abstract: Prior work has shown that the vestibular system contributes to regulating activity of upper airway muscles including the tongue protruder muscle genioglossus. The goal of the present experiments was to determine whether electrical vestibular stimulation could potentially be used to alter genioglossal activity in awake animals. Six adult cats were instrumented for recording of EMG activity from genioglossus, abdominal musculature, and triceps. In addition, a silver ball electrode was implanted on the round window for stimulation of vestibular afferents. Subsequently, stimulation and recordings were conducted while animals were awake. In all cases, stimulation using single shocks or trains of pulses > 100 μA in intensity produced responses in all muscles, including genioglossus. The latency of the genioglossal response was approximately 12 msec, and delivering continuous current trains to the labyrinth chronically elevated the muscle's activity. Although a number of muscles were affected by the stimulus, animals experienced no obvious distress or balance disturbances. Vestibular stimulation remained effective in producing genioglossal responses until experiments were discontinued 1–2 months following onset. These data suggest that electrical vestibular stimulation could potentially be used therapeutically to alter upper airway muscle activity.
Keywords: upper airway, tongue musculature, respiration, vestibular system
