Medulla oblongata

Jump to navigation Jump to search

Template:Infobox Brain

WikiDoc Resources for Medulla oblongata


Most recent articles on Medulla oblongata

Most cited articles on Medulla oblongata

Review articles on Medulla oblongata

Articles on Medulla oblongata in N Eng J Med, Lancet, BMJ


Powerpoint slides on Medulla oblongata

Images of Medulla oblongata

Photos of Medulla oblongata

Podcasts & MP3s on Medulla oblongata

Videos on Medulla oblongata

Evidence Based Medicine

Cochrane Collaboration on Medulla oblongata

Bandolier on Medulla oblongata

TRIP on Medulla oblongata

Clinical Trials

Ongoing Trials on Medulla oblongata at Clinical

Trial results on Medulla oblongata

Clinical Trials on Medulla oblongata at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Medulla oblongata

NICE Guidance on Medulla oblongata


FDA on Medulla oblongata

CDC on Medulla oblongata


Books on Medulla oblongata


Medulla oblongata in the news

Be alerted to news on Medulla oblongata

News trends on Medulla oblongata


Blogs on Medulla oblongata


Definitions of Medulla oblongata

Patient Resources / Community

Patient resources on Medulla oblongata

Discussion groups on Medulla oblongata

Patient Handouts on Medulla oblongata

Directions to Hospitals Treating Medulla oblongata

Risk calculators and risk factors for Medulla oblongata

Healthcare Provider Resources

Symptoms of Medulla oblongata

Causes & Risk Factors for Medulla oblongata

Diagnostic studies for Medulla oblongata

Treatment of Medulla oblongata

Continuing Medical Education (CME)

CME Programs on Medulla oblongata


Medulla oblongata en Espanol

Medulla oblongata en Francais


Medulla oblongata in the Marketplace

Patents on Medulla oblongata

Experimental / Informatics

List of terms related to Medulla oblongata

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

The medulla oblongata is the lower portion of the brainstem. It deals with autonomic functions.


By anatomical terms of location, it is rostral to the spinal cord and caudal to the pons, which is in turn ventral to the cerebellum.

For a human or other bipedal species, this means it is above the spinal cord, below the pons, and anterior to the cerebellum.


Two parts: open and closed

The medulla is often thought of as being in two parts:

  • an open part (close to the pons)
  • a closed part (further down towards the spinal cord).

The opening referred to is on the dorsal side of the medulla, and forms part of the fourth ventricle of the brain.

Landmark fissures and sulci

The medulla has an anterior median fissure and a posterior median sulcus corresponding to the structures seen in the spinal cord.

On each side, the anterolateral sulcus lies in line with the ventral roots of the spinal nerves. The rootlets of cranial nerve XII (the hypoglossal nerve) emerge from this sulcus.

The posterolateral sulcus lies in line with the dorsal roots of the spinal nerves. It gives attachment to the rootlets of the glossopharyngeal, vagus and the accessory nerve or the IX, X, and the XI cranial nerves from above downward in order.

Between the anterior median sulcus and the anterolateral sulcus

The region between the anterior median sulcus and the anterolateral sulcus is occupied by an elevation on either side called as the pyramid of medulla oblongata. This elevation is caused by the corticospinal tract.

In the lower part of the medulla some of these fibers cross each other thus obliterating the anterior median fissure. This is known as the decussation of the pyramids.

Some other fibers that originate from the anterior median fissure above the decussation of the pyramids and run laterally across the surface of the pons are known as the external arcuate fibers.

Between the anterolateral and posterolateral sulci

The region between the anterolateral and posterolateral sulci in the upper part of the medulla is marked by a swelling known as the olive.

It is caused by a large mass of gray matter known as the inferior olivary nucleus.

Between the posterior median sulcus and the posterolateral sulcus

The posterior part of the medulla between the posterior median sulcus and the posterolateral sulcus contains tracts that enter it from the posterior funiculus of the spinal cord. These are the fasciculus gracilis, lying medially next to the midline, and the fasciculus cuneatus, lying laterally.

These fasciculi end in rounded elevations known as the gracile and the cuneate tubercles. They are caused by masses of gray matter known as the nucleus gracilis and the nucleus cuneatus.

Just above the tubercles, the posterior aspect of the medulla is occupied by a triangular fossa, which forms the lower part of the floor of the fourth ventricle. The fossa is bounded on either side by the inferior cerebellar peduncle, which connects the medulla to the cerebellum.

Lower part

The lower part of the medulla, immediately lateral to the fasciculus cuneatus, is marked by another longitudinal elevation known as the tuberculum cinereum.

It is caused by an underlying collection of gray matter known as the spinal nucleus of the trigeminal nerve.

The gray matter of this nucleus is covered by a layer of nerve fibers that form the spinal tract of the trigeminal nerve.


The base of the medulla is defined by the commissural fibers, crossing over from the ipsilateral side in the spinal cord to the contralateral side in the brain stem; below this is the spinal cord.


The medulla oblongata controls autonomic functions, and relays nerve signals between the brain and spinal cord. It is also responsible for controlling several major points and autonomic functions of the body:

Blood supply

Blood to the medulla is supplied by a number of arteries.

Additional images

External links


ca:Bulb raquidi cs:Prodloužená mícha da:Medulla oblongata de:Medulla oblongata lb:Verlängert Muerch nl:Medulla oblongata sk:Predĺžená miecha sr:Продужена мождина fi:Ydinjatke sv:Förlängda märgen uk:Довгастий мозок

Template:WikiDoc Sources