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| Medulla Oblongata, Teachmeanatomy image |
Medullar oblongata simply known as Medulla, is the, most posterior (caudal) part of the brain stem, it is continuous with the spinal cord, extending from the lower body of the decussation of the pyramid to the pons. Its ventral surface resembles that of a spinal cord except for the bilateral prominence of the olive
It has thick walls and floor but with thin roof, the dorsal surface of its half forms part of the floor of the fourth ventricle. It has motor nuclei which include the hypoglossal nuclei, dorsal motor nuclei, inferior salivatory and the ambiguus nucleus.
It also has sensory nuclei which include the nuclei of the posterior column (gracile and cuneate), the cochlear and the vestibular nuclei, the mild and the caudal portions of the spinal trigeminal nucleus and nucleus of the solitary tract.
Functions of Medullar Oblangata
The medullar oblongata is primarily concerned with coordination of impulses from lateral line, ear taste and touch receptors.
It is important in the controls involuntary actions such as heart beats, respiration (breathing), movement and peristaltic action of the intestine.
It is the site where glossopharyngeal and vagus nerve arise from.
Definitions of terms
Caudal: Caudal is the tail or posterior part of the body.
Cuneate: cuneate, is used to describe something that is wedge shape, and having a narrow part at the base.
Olive: Body part of the medullar.
Vagus: Vagus is any one of the tenth pair of the cranial nerve originating the brain stem and extending down into the abdomen, they are the nerve that supply the tongue, larynx, lung , gut and heart.
Glossopharyngeal: Glossopharyngeal, simply means, relating to the tongue and pharynx.
Pons: The pons is a band of nerve fiber found in the brain stem.
Decussation: crossing of lines.
Ambiguus nueleus: Ambiguus nucleus is a large group of motor neurons located deep in the medullary reticular formation, it contains the cell body of nerves that innervate the muscles of the soft plate, pharynx and larynx which are associated with speech and swallowing.
