We explain what the medulla oblongata is and its anatomy and structure. We also explain its characteristics and functions.
What is the medulla oblongata?
The medulla oblongata or brainstem It is located on the nape of the neckbetween the spinal cord and the brain stem bridge. It is an extension of the spinal cord.
It is through this medulla oblongata that nerve impulses from the spinal cord and the peripheral nervous system reach the brain.
Here the nerves of both cerebral hemispheres cross and it is precisely where the nerves coming from the right hemisphere separate and go to the left side and vice versa.
Stimuli from the body pass without exception through the medulla oblongata. In this way the brain is informed of what is happening in the different parts of the body.
See also: Cerebellum
Historical studies on the medulla oblongata
The history of neurology It has its beginnings and notable advances with the figure of Pierre Flourens (1794-1867), French biologist who conducted theoretical and practical research on animals.
It is considered one of the founders of experimental neurobiology. It was he who discovered that the elimination or involvement of the medulla oblongata produces death.
Morphology of the medulla oblongata
It is shaped like a truncated cone. but with the base facing up and backwards.
Its measures are: 1.5 cm in diameter; 3 cm high and 1.3 cm thickIts weight is between 6 and 7 gr.
Limits of the medulla oblongata
It’s found located between the spinal cord and the brainstem pons. It borders on the upper part with the lower edge of the pons and on the lower part with the spinal cord at the decussation of the pyramids.
Anatomy of the medulla oblongata
For its study it is divided into 3 thirds:
- Lower third. Where the pyramidal decussation is located.
- Middle third. Where sensory decussation occurs.
- Upper third. Where bulbar olives are found.
External organization of the medulla oblongata
The medulla oblongata constitutes a lower part of the brain stem. It is divided into 3 faces:
- Previous face. Here there is a canal or groove called the anterior median fissure that continues the structure of the same name present in the spinal cord. On its sides are pyramids that form a kind of white columns and this is precisely where the nerve fibers cross from one hemisphere to the opposite side of the body. There the decussation of the pyramids are formed. Towards the outside of these pyramids is the pre-olivary groove. This is where the greater hypoglossal nerve originates.
- Side face. On the sides of each pyramid there is an oval-type area called olive. This area marks the inferior olivary nucleus. Behind this is the posterolateral sulcus, where the glossopharyngeal, vagus and accessory nerves are found.
- Upper side. In the middle area is the posterior median sulcus. On both sides the cord of Goll and the cord of Buldach arise and divide.
Internal organization of the medulla oblongata
Regarding its internal organization, it is subdivided into 4 parts or levels:
- Decussation level of the pyramids
- Level of decussation of the lemnisci
- Olive level
- Lower level or brainstem bridge
Main function of the medulla oblongata
The medulla oblongata ensures the entry and exit of information between the brain and the peripheral nervous system (SNP). It connects all the information that comes from the body so that the brain is informed and acts accordingly.
In other words, the medulla oblongata is in charge of basic and vital functions. In case of accidents, death occurs immediately due to respiratory or cardiac arrest.
Other functions of the bulb spinal
- Regulates the secretion of gastric juices from the stomach
- Controls sneezing, swallowing, vomiting and coughing as well as all the muscles involved in these tasks
- Regulates balance
- It acts on phonation
- It intervenes in the person’s awakening every morning. This is where the phrase “internal clock” comes from.
- Regulates eye movement
Complications of the body
Some complications of the body can affect the medulla oblongata. Some examples are:
- Congenital or degenerative problems
- Vascular complications
- Tumors
- Problems with metabolic origin of infectious and inflammatory characteristics
Pathologies of the medulla oblongata
- Multiple system atrophy
- Lateral sclerosis
- Amyotrophic Lateral Sclerosis
- Cancer of the medulla oblongata
- Multiple sclerosis