nucleus ambiguus

anatomy

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Last updated

July 1, 2026

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The nucleus ambiguus is a collection of nerve cell bodies located in the medulla oblongata of the brainstem. It is part of the motor component of the vagus nerve (cranial nerve X) and the glossopharyngeal nerve (cranial nerve IX). These nerves control muscles in the pharynx, larynx, and esophagus, which are essential for swallowing and speech. Damage to the nucleus ambiguus can lead to difficulties in swallowing and speaking, and in severe cases, can be life-threatening due to potential airway obstruction.12

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human nervous system
Parasympathetic nervous system
…the ventral medulla called the nucleus ambiguus, while those that control functions of the gastrointestinal tract arise from the dorsal vagal nucleus. After exiting the medulla in the vagus nerve and traveling to their respective organs, the fibers synapse on ganglion cells embedded in the organs themselves. The vagus nerve…
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…the ventral medulla called the nucleus ambiguus, while those that control functions of the gastrointestinal tract arise from the dorsal vagal nucleus. After exiting the medulla in the vagus nerve and traveling to their respective organs, the fibers synapse on ganglion cells embedded in the organs themselves. The vagus nerve…
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human nervous system
Accessory nerve (CN XI or 11)
…cranial root originates from the nucleus ambiguus and exits the medulla below the vagus nerve. Its fibers join the vagus and distribute to some muscles of the pharynx and larynx via pharyngeal and recurrent laryngeal branches of that nerve. For this reason, the cranial part of the accessory nerve is,…
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…cranial root originates from the nucleus ambiguus and exits the medulla below the vagus nerve. Its fibers join the vagus and distribute to some muscles of the pharynx and larynx via pharyngeal and recurrent laryngeal branches of that nerve. For this reason, the cranial part of the accessory nerve is,…
Read More