Characteristics And Functions Of The Cerebral Ventricular System

The nervous system, this great conductor that we have in us, is made up of different parts that interact with each other and perform various functions. Thus, it has systems that allow its proper functioning. This is the case with the ventricular system. Indeed, it is nothing more than a system of small reservoirs linked together, in the image in a way of a “sewage system”.

Inside the cranium is the brain, and inside it is the brain. The ventricular system, on the other hand, is located in the brain. It consists of four ventricles. This system’s role is to maintain, protect and structure our brain. Although we have not all heard of this system, it is of paramount importance.

In this article, we will focus on the ventricular system in order to define it, distinguish each of its cavities and functions and explore some of the pathologies associated with it. Let’s go!

What is the ventricular system and where does it come from?

First of all, the set of cerebral ventricles make up the ventricular system. It is a system made up of structures, kinds of cavities, linked together. The cerebrospinal fluid (CSF) starts there and circulates in these cavities. It is a clear liquid that bathes the brain and spinal cord.

The ventricular system develops alongside the rest of the central nervous system. This facilitates the process of circulating CSF. Around the 26th day of embryonic development, differentiation of the optic ventricle begins. It is later that evagination of the midline of the mesencephalon begins. This will later form the cerebral aqueduct.

Around the sixth week, the development of the interventricular foramen begins. The formation of the choroid plexuses and lateral ventricles also begins. Then, the furrows and the segmentation gradually become more visible.

Later, there is a growth of the median and lateral ventricular eminences and the spherical shape of the lateral ventricle then takes the shape of a C. The horns of the lateral ventricles thus begin to stand out. In addition, a small pocket forms on the diencephalic floor. It will soon be the 3rd ventricle. During this time, the choroid sacs of the 4th ventricle continue to develop.

Finally, during weeks 7 and 8, the horns complete their growth and the vesicular form takes on its final appearance. The isthmic part is compressed by the growing cerebellum, and many villi extend to the midline.

Structure

The ventricular system is made up of four ventricles linked together by channels and openings. Let’s take a look at each of its parts:

• The lateral ventricles: this is actually the first and second ventricle. They are located in both cerebral hemispheres and have an anterior tube which is oriented towards the frontal lobe and a posterior tube which is oriented towards the temporal lobe. They are connected to the third ventricle through Monro’s ventricular hole. Finally, the ventricles are C-shaped and their volumes increase throughout life.

• The third ventricle: it consists of a thin flattened cavity located between the two thalamic nuclei and crossed by the interthalamic commissure. Its connection with the rest of the system is through the Sylvius cerebral aqueduct (or the midbrain aqueduct). It has two protuberances: the supra-optic recess, located above the optic chiasm, and the infundibular recess, which is located above the optic nerve.
• The fourth ventricle: it extends from the midbrain aqueduct to the central canal, at the top of the spinal cord. Its floor is formed by the rhomboid pit and communicates with the central channel through the Luschka and Magendie holes. This is also where the CSF exits to the subarachnoid space. In addition, it is connected to subarachnoid reservoirs which allow the CSF to reach the subarachnoid space.

Then, when they reach the spinal cord, the ventricles continue to pass through the ependymal duct, a cavity that begins at the end of the fourth ventricle and runs all the way inside the spinal cord until it ends. to the first vertebra in the lumbar region.

Functions of the cerebral ventricular system

As we will see below, the ventricular system performs different tasks:

• The production of CSF: this is indeed its main function, although it shares it with other structures, such as the subarachnoid space
• Preserving the brain: CSF helps maintain internal brain homeostasis by maintaining adequate intracranial pressure. In addition, this fluid helps in the elimination of waste, which allows the brain to maintain a healthy environment for its proper functioning.

• Brain buoyancy: Thanks to CSF, the brain is floated, which helps reduce its weight from about 1400 grams to about 50 grams
• Defense: CSF allows us to defend ourselves against external aggressions that could be dangerous for our brain. It also increases the degree of protection of our brain against trauma in case of shock.

Diseases of the ventricular system

The ventricular system can undergo various kinds of disorders. Here are a few :

• Hydrocephalus: This is a problem that causes overproduction of CSF. As it grows, it then causes high intracranial pressure and can lead to cerebral atrophy, metabolic and cognitive disorders, and even death.
• Meningitis: this consists of inflammation of the meninges due to an infectious cause which is generally caused by a virus, fungi or bacteria. This inflammation then produces an increase in intracranial pressure. As a result, it makes it difficult for the CSF to flow and causes symptoms such as headache, nausea, sensitivity to light, fever and cognitive impairment, among other things.

• Ventriculitis: Ventriculitis is an inflammation of the ventricles of the brain which increases intracranial pressure and impairs the normal flow of CSF and the proper functioning of the vascular system. It can be accompanied by hydrocephalus and produce, among other pathologies, encephalitis or inflammation of the brain.
• Alzheimer’s disease: As Alzheimer’s disease progresses, the deterioration and destruction of neurons increases. This therefore leads to a decrease in neuronal density. The space freed by the resulting decrease in volume is then occupied by the ventricles, which gradually dilate
• Schizophrenia: Some studies suggest that people with schizophrenia have larger ventricles in their brains. In fact, Jordi E. Obiols and Marta Carulla, from the Autonomous University of Barcelona, ​​published an article in the journal Psicología Conductual . They suggest that schizophrenic patients present with ventricular dilation as well as cortical decline, which could be evidence that this disease has a neurological origin.

In conclusion

As we have seen, the ventricular system is therefore a fundamental part of our organism. Its dysfunction causes serious disturbances to our metabolism.

Thus, we can see our ventricular system as a kind of shield that protects us in the face of adversity. In addition, its role is to maintain the internal balance of our body and eliminate harmful agents.

Our thoughts

Cerebrospinal fluid (CSF) or cerebrospinal fluid is one of the main fluids in the human body. Its main function is to protect …