Meninges: What Are They And What Are They Used For?
The meninges act as a physical filter, absorbing shocks, but also as protection against chemical agents. In this article, we explain in detail what their functions are.
The meninges are a fundamental part of our central nervous system. It is a set of membranes that cover both the spinal cord and the brain, the main function of which is to protect them against certain attacks.
The word meninge comes from the Greek, where mēninx means membrane. The central nervous system is one of the parts of the body that is most in need of protection, because it is thanks to it that we can perform all of our functions, such as breathing.
There are three meninges: pia mater, arachnoid and dura. In this article, we want to explain how they are distributed as well as introduce you to their main features and functions. We will also talk about meningitis and why it is such a dangerous pathology.
What are the meninges?
As we mentioned, the central nervous system needs different protective mechanisms to ensure our life. First of all, it is protected by bony structures, like the skull and spine.
But it is also made up of a series of membranes which above all protect it from chemical attacks or infections: the meninges. These are three membranes or layers that are separated from each other by spaces that also contain important structures.
If we start from the outermost part, in contact with the skull, we find the dura. This meninge is attached to the bone and emits a sort of partition which divides the cranial cavity into several parts. In this way, it keeps the different parts of the brain in place. It also contains the venous sinuses.
The arachnoid is the next meninge, located in between. It is so named because it looks like a spider’s web. It is the most delicate and fragile layer. Below is the subarachnoid space, which contains the cerebrospinal fluid.
The pia mater is the innermost part of the meninges, located in contact with the brain and the spinal cord. This meninge covers the brain and is introduced by furrows and convolutions, as if it were a thin sheet covering it.
The spaces between the meninges
We have already mentioned the subarachnoid space, which is that between the arachnoid and the pia mater meninge. It contains cerebrospinal fluid. This fluid protects the central nervous system, by cushioning shocks and pressure changes inside the skull.
Between the dura mater and the arachnoid we find the subdural space. Above the dura is the famous epidural space, known because some anesthetic drugs are injected into it, for example during pregnancy. This space is present in the spinal cord, but not in the brain.
What are the functions of the meninges?
As we all know, the main function of the meninges is to protect the nervous system from injury such as trauma. In other words, they are responsible for absorbing any shocks you might receive. However, they also act as a filter for chemical attack.
In addition, the meninges allow cerebrospinal fluid to flow through the system. This fluid, in addition to providing physical protection, helps remove wastes from the brain and also balances the pressure inside the skull.
The meninges thus form a support and protection system. On the other hand, they inform the brain about certain changes in pressure, tension or pain caused by an injury.
What is meningitis?
Meningitis is a condition that occurs due to inflammation of the meninges. Most cases are caused by a viral infection, although it can also be caused by bacteria or fungus. It can even be caused by a cancerous process or other reasons.
The problem with meningitis is that this inflammation can often cause brain damage. It often leads to consequences such as deafness or impairment of other senses. In fact, it can be fatal.
The bottom line is that the meninges are the basic protective structures of the central nervous system. It is therefore very important that they are maintained in good health, as an injury can compromise the integrity of this system.
