Selective stimulation of the hypoglossal nerve

The main objective of this study is to dilate the pharynx by selective activation of the lingual musculature through electrical stimulation of the hypoglossal nerve. A flat-interface-nerve-electrode (FINE) with nine contacts was implanted on the proximal hypoglossal nerve trunk in a dog. The evoked electromyogram signals were recorded with wire electrodes from the genioglossus, geniohyoid, styloglossus, and hyoglossus muscles. Genioglossus or geniohyoid was activated selectively without significant activation of other muscles within a window of the stimulus current. A FINE design with a smaller inter-contact distance may be needed to selectively activate the remaining two extrinsic tongue muscles also.