Human cerebellum: its parts and functions
The cerebellum it is much more than a kind of younger brother of the neocortex, cornered half hidden between the occipital lobe and the brainstem. In fact, this curious structure resembling a ball of flattened wool is one of the most important parts of the brain.
Moreover, it is considered that in most cases the proper functioning of the cerebellum is essential for us to survive and cases in which this rule is not met become news.
Although it is a structure apparently quite discrete because it is partly hidden by the cerebral cortex, the cerebellum is one of the areas of the brain with the highest density of neurons . In fact, about half of the neurons in the brain are located in this structure. But ... why is it so important that the cerebellum be in good condition? What processes are you responsible for?
The functions of the cerebellum
It's been years since the functioning of the cerebellum and the coordination of muscle activation has been related . Thus, it was considered that the task of the cerebellum was, basically, to make it possible for us to maintain balance, that we can coordinate simple and complex movements and, in general, that the muscles of our body respond faithfully and effectively to the commands issued by the body. brain.
For example, it was considered that one of the main symptoms of alterations in the cerebellum is the loss of balance after drinking too much alcohol. However, in recent years it has been discovered that the idea that the role of the cerebellum has to do with motor coordination is too simplistic. A) Yes, the cerebellum does not only intervene in the motor processes, but also plays an important role in many other functions .
The cerebellum in the regulation of emotions
One of the connection routes of the cerebellum unites this structure with large areas of the limbic system, which is the one that is related to the appearance and maintenance over time of the emotional states that dye our experiences. By being in communication with structures such as the amygdala, the cerebellum has the ability to intervene in the regulation of the emotional states that appear .
Thus, for example, part of the functions of the cerebellum have to do with creating associations between sensations and feelings, which serves as support for future learning by relating certain experiences with specific feelings.
The cerebellum and cognitive processes
The fact that the cerebellum has such a density of neurons and that it is connected to large areas of the cerebral cortex means that the idea that it has something to do with cognitive processes such as memory or attention management does not sound outlandish. Currently there are some investigations that point in that direction.
For example, it has been seen that the size of the cerebellum could be related to the level of intelligence you have . In addition, from studies in which the effects that a lesion in the cerebellum has on the mental capacities of patients are observed, it has been possible to relate the dysfunction in this structure with attention deficits and the use of language.
The difficulty of investigating this is that from these studies based on cases of cerebellar injury, it is not known if the decrease in cognitive abilities is due to the fact that the neurons involved in them have died (since they are located in the area of the brain). injury) or if these effects are due to an imbalance in the functioning of the brain caused by the wound. So that, you need to investigate much more to know if the role of the cerebellum in cognitive functions is as important as those studies seem to suggest.
The cerebellum and motor coordination
The old ideas about the role of the cerebellum as the coordination center of muscle activation have not been refuted. Today it is still considered that this structure has a leading role in the coordination of movements, maintenance of balance and monitoring of neuronal signals aimed at activating muscles.
Since the cerebellum is connected to many areas of the brain, it crosses the motor information elaborated in the upper regions of the brain with the most "concrete" and operational motor information aimed at activating muscle fibers, and checks that there are no inconsistencies between the two. Further, there is a debate generated around the possibility that one of the functions of the cerebellum is motor learning , that is, the ability to polish a pattern of movements to be perfected more and more.
Structure of the cerebellum
The cerebellum may be relatively small, but its composition is very complex . Although we can talk at length about the different parts and subdivisions of the parts of the cerebellum, this time we will focus only on the broader categorization of the structures of the cerebellum, that is, the parts that can be seen with the naked eye ease (as long as you have an encephalon ahead, of course).
The hemispheres of the cerebellum
The cerebellum resembles the rest of the brain in that it is also covered by a layer of cells that create a wrinkled and rough surface. Although, yes, in the case of the cerebellum these folds are even tighter and thinner, as can be seen with the naked eye. That is why one of the structures or subregions of the cerebellum is known as the cerebellar cortex .
The cortex of the cerebellum is divided into two cerebellar hemispheres, in the same way that the cerebral cortex is divided into a right hemisphere and a left hemisphere. In the middle of these hemispheres is a region called vermis , which is a vertical strip that joins both parts and connects them to each other.
The lobes of the cerebellum
Beyond this classification of parts of the cerebellar cortex, there are several lobes of the cerebellum, in the same way that each hemisphere of the cerebral cortex is divided into lobes of the brain. These lobes are the anterior lobe, the posterior lobe, and the flocculonodular lobe, arranged from the top to the bottom.