Function and Lesions of Nucleus Ambiguus - Controls motor innervation of ipsilateral muscles of the soft palate, pharynx, larynx, and upper esophagus - Lesions result in nasal speech, dysphagia, dysphonia, and deviation of the uvula toward the contralateral side - Plays a role in speech and swallowing - Innervates postganglionic parasympathetic neurons in the heart

Areas supplied by Nucleus Ambiguus - Muscles supplied by the vagus nerve, including levator veli palatini, are necessary for proper swallowing - Integration by the nucleus of the solitary tract is involved in swallowing - Vagus nerve supplies upper part of the esophagus, pharynx, and larynx - External formation of the nucleus ambiguus contains cholinergic preganglionic parasympathetic neurons for the heart - These neurons have a cardioinhibitory effect

Cardiac and Bronchopulmonary Effects of Nucleus Ambiguus - Nucleus ambiguus, along with sympathetic outflow, regulates quick changes in blood pressure - Parasympathetic outflow from the nucleus ambiguus and dorsal motor nucleus of the vagus nerve decreases cardiac activity in response to fast increases in blood pressure - External formation of the nucleus ambiguus sends bronchoconstrictor fibers to the bronchopulmonary system - This can cause reflexive decreases in pulmonary bronchial airflow - Role in bronchospastic diseases like COPD/emphysema and asthma, particularly for exercise-related asthma exacerbations

Additional Images of Nucleus Ambiguus - Section of the medulla oblongata at about the middle of the olive - Schematic representation of cranial nerve nuclei, showing motor nuclei in red and sensory nuclei in blue - Schematic representation of nuclei of origin of cranial motor nerves, shown in a lateral view - Transverse section of the medulla oblongata, showing the formatio reticularis - Images provide visual representation of the nucleus ambiguus and its location in the medulla oblongata

Related Concepts and References - Solitary nucleus, another important nucleus in the medulla oblongata - Related nucleus involved in sensory processing and integration - Provides additional context and understanding of the neural circuitry in the medulla oblongata - Relevant research articles and studies related to the nucleus ambiguus and its functions - Additional resources and information for further exploration of the topic provided by Medical Neurosciences