Transmission of Taste Information from the Tongue to the Brain comes from three nerves that contact taste cells have cell bodies in ganglia and send axons to the solitary tract nucleus (NST) of the medulla in a topographic order. Dendrites from the chorda tympani (a branch of the facial nerve VII) contact the anterior (2/3) tongue, cell bodies reside in the geniculate ganglion, and axons terminate in the rostral pole of the NST. Dendrites from the lingual-tonsillar branch (glossopharyngeal nerve IX) contact the posterior (1/3) tongue, have cell bodies in the petrosal ganglion, and have axons that invade the NST at intermediate regions. Dendrites from the superior laryngeal branch (vagus nerve X) innervate the epiglottis and esophagus, have cell bodies in the nodose ganglion, and send axons to the caudal regions of the NST. Thus, information from the anterior-posterior tongue is represented from the rostral to caudal NST.
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