<prompt> True about vagal nuclei are all except-There are 4 vagal nucleiThey are found in the floor of 4th ventricleNucleus Ambiguous is a vagal nucleusSpinal trigeminal nucleus is not a vagal nucleus  <response>: Ans. is d i.e., Spinal trigeminal nucleus is not a vagal nucleus The vagus nerve includes axons which emerge from or converge onto four nuclei of the medulla. They are present deep in the medulla in the floor of the 4th ventricle. These nuclei are:-1. The dorsal nucleus of vagus nerve -- which sends parasympathetic output to the viscera, especially the intestines2. The nucleus ambiguus -- which gives rise to the branchial efferent motor fibers of the vagus nerve and preganglionic parasympathetic neurons that innervate the heart3. The solitary nucleus -- which receives afferent taste information and primary afferents from visceral organs4. The spinal trigeminal nucleus -- which receives information about deepcrude touch, pain, and temperature of the outer ear, the dura of the posterior cranial fossa and the mucosa of the larynx 