The main difference between cerebellum and medulla oblongata is that the cerebellum maintains the balance of the body and coordinates the muscular activities, whereas the medulla oblongata controls the activity of the internal organs and many other involuntary actions.
The brain is a complex organ located in the skull and controls many functions such as thought, touch, emotions, temperature, breathing, etc. It acts as the center of the nervous system. The three main parts of the brain are the forebrain, midbrain, and hindbrain. The brain is further divided into several parts, and each part has a specific function or several functions. Cerebellum and medulla oblongata are two main parts of the brain with specific functions.
Key Areas Covered
1. What is Cerebellum
– Definition, Location, Function
2. What is Medulla Oblongata
– Definition, Location, Function
3. Difference Between Cerebellum and Medulla Oblongata
– Comparison of Key Differences
Brain, Cerebellum, Medulla Oblongata
What is Cerebellum
Cerebellum is the portion of the brain that is located at the back of the head, between the cerebrum and the brain stem. It is located immediately inferior to the occipital and temporal lobes and within the posterior cranial fossa. Cerebellum is separated from these lobes by a very tough layer of the dura mater called tentorium cerebelli.
Cerebellum is smaller than the cerebrum but holds a large number of neurons. It contains 80% of the brain’s neurons organized in a dense cellular layer. The name cerebellum comes from Latin and has the meaning “little brain.”
Furthermore, the cerebellum performs many functions. Some of them are coordinating the movements of the trunk, including the thorax, neck, shoulders, abdomen, and hips, providing the planning of sequential movements of the entire body along with involvement in the conscious assessment of the movement of errors, and making fine adjustments for motor actions.
Divisions of the Cerebellum
The cerebellum has two hemispheres. They are connected by a midline area called the vermis. We can also divide the cerebellum according to its anatomical lobes, functions, or zones.
Division according to the anatomical lobes consists of three subdivisions: anterior lobe, posterior lobe, and flocculonodular lobe. Two fissures divide these lobes: the posterior lateral fissure and the primary fissure. Considering the division of the cerebellum according to zones, there are three cerebellar zones: the midline vermis and the intermediate zones on either side, with the lateral hemispheres located further out from the intermediate zone.
According to the functions, the cerebellum has three main parts.: vestibulocerebellum, spinocerebellum and cerebrocerebellum. Cerebrocerebellum, which is the largest, regulates the coordination of muscle activation for complex movements, as well as the planning and execution of visually-guided movements. Moreover, the spinocerebellum is involved in regulating the body’s movements by allowing for error correction. Meanwhile, the vestibulocerebellum takes part in controlling balance and ocular reflexes, mainly the fixation of a target.
What is Medulla Oblongata
The medulla oblongata is the bottommost part of the brain. It is located where the brain and spinal cord connect. It is connected to the pons by the midbrain. The medulla oblongata is a part of the brain stem. It is continuous posteriorly with the spinal cord, with which it merges at the opening (foramen magnum) at the base of the skull. There are two main parts of the medulla oblongata: the ventral medulla and the dorsal medulla. The ventral medulla is known as the frontal portion, while the dorsal medulla is known as the rare portion or the tegmentum. The ventral medulla is comprised of a pair of structures called the pyramids, and it also contains paired structures known as the olivary bodies, which are located lateral to the pyramids.
The medulla generally has the shape of a funnel or tube and is at its widest at its top. It is beige or off-white in color with a slight tint of pink. Though the medulla has many functions, it is very small in structure. Its widest diameter is 0.78 inches and 1.1 inches long.
There is both white matter (myelinated fibers) and grey matter (unmyelinated) nerve fibers in the medulla oblongata. The medulla oblongata transmits signals between the spinal cord and the higher part of the brain. It also manages heart, circulation, and breathing, manages other autonomic processes, and acts as a crossover point.
Difference Between Cerebellum and Medulla Oblongata
The cerebellum is a part of the brain located at the back of the skull, beneath the cerebral hemispheres, while the medulla oblongata is a part of the brainstem located between the spinal cord and the pons.
The cerebellum maintains the balance of the body and coordinates muscular activities, whereas the medulla oblongata controls the activity of the internal organs and many other involuntary actions.
Moreover, the cerebellum is located behind the head, below the temporal and occipital lobes, and just above the brain stem. On the other hand, the medulla oblongata is the lowermost section of the brain and the bottom part of the brain stem.
Cerebellum is the size of a fist, whereas the medulla oblongata is 1.1 inches long, and its diameter at the widest area is 0.78 inches.
In brief, the cerebellum and medulla oblongata are two different parts of the brain, performing different functions. The main difference between cerebellum and medulla oblongata is that the cerebellum maintains the balance of the body and coordinates the muscular activities, whereas the medulla oblongata controls the activity of the internal organs and many other involuntary actions.
1. “Three lobes of the cerebellum — 04” – from BodyParts3D by DBCLS (CC BY-SA 2.1 jp) via Commons Wikimedia
2. “Olive (medulla oblongata) – lateral view” – from BodyParts3D by DBCLS (CC BY-SA 2.1 jp) via Commons Wikimedia