The brain is one of the most fundamental organs for the human being, governing both mental processes and cognitive-emotional capacities as well as the different systems and organs of the body, including the control of vital signs.
It is therefore a fundamental and essential organ for life, and certain protection is necessary against any possible damage that could come from the outside. The skull is an excellent protective barrier, but it is not the only barrier present.
There are a series of membranes called meninges between the skull and the brain which also serve, among other things, as protection for the brain and the entire nervous system. One of them is the dura mater.
The meninges are a series of three membranes called the dura mater, arachnoid mater, and pia mater that surround and protect the brain. These membranes are located between the skull and the brain, being located one after the other and different blood vessels and fluids such as cerebrospinal fluid circulating between them. Their presence is not only present in the brain, which they cover in its entirety, but in addition to this they are present in a large part of the spinal cord.
The most external of the three and to which this article is dedicated is the dura mater It is the thickest and most resistant meninge, in close contact with the skull. Its rigidity and the different extensions that it has covering the brain make it retain its shape and internal consistency. It also contains a large part of the veins that collect the blood used by the brain and return it to the heart. The dura mater very precisely covers most of the nervous system, reaching from the brain to the sacral vertebrae of the spinal cord.
Both the dura mater and the rest of the meninges contain and are connected by different nerve fibers, possessing multiple pressure and pain receptors In the dura mater itself, the presence of the trigeminal and vagus nerves, as well as the first three spinal nerves, stand out. It is, in short, a layer of the meninges that acts as a “bridge” between the central nervous system and the elements of the body that are beyond.
Anatomical structure of the dura mater
If we analyze the dura mater and its composition, we can see how this meninge has and It is mainly composed of two large layers, the periosteal layer and the meningeal layer starting from the last four large partitions that divide the skull cavity into different parts or cells.
1. Periosteal layer
The first of the layers of the dura mater is the so-called periosteal or endosteal layer, this being the part of the meninge that is attached to the skull. It is in this layer where most of the blood vessels that supply the brain can be found. It is found only at the cranial level, not being present in the spinal cord.
2. Meningeal layer
Later you can find the meningeal layer, which is very strong and has a high collagen content. It is from this layer where a series of partitions extend, which are what contribute to shaping the brain maintaining the boundaries between the different structures.
These septa of the dura mater, which divide the cranial cavity into different cells, are as follows.
The sickle name of this septum is due to the fact that it cuts or divides the cerebral fossa into two parts. It is located in the middle part of the skull, vertically.
2.2. cerebellar tent
This dural septum separates the occipital lobes and the cerebellum. Protects the midbrain. It also delimits and protects the trigeminal nerve.
23. falx cerebellum
As in the sickle of the brain, This septum keeps one of the brain structures divided into two halves In this case, this septum keeps the two cerebellar hemispheres separated.
2.4. Pituitary tent
It is a partition that surrounds the sella turcica part of the skull where the pituitary gland is housed, which it protects.
Principal functions
The existence of the dura mater is a great advantage for human survival The main functions of this membrane, although they have been glimpsed previously, are the following.
1. Protects the brain and spinal cord
The main function of the dura mater and the other meninges is to protect the nervous system This protection occurs both on a biological level, since it acts as a filter that makes it difficult for external harmful agents to enter, and on a physical level, since between the presence of the skull, the membrane itself and the cerebrospinal fluid, it is difficult for blows to occur. affect and damage the brain.
2. Helps maintain the shape of the brain
The division into cells of the cranial cavity, which occurs thanks to the septa of the dura mater, allows the structure of the different locations and parts of the brain to be maintained as well as its general shape.
The presence of the meninges keeps the brain in place limiting the displacement that could occur due to the mere movement of the body.
4. They irrigate the brain
in the dura mater a large number of blood vessels are found, especially those responsible for returning to the heart the blood from which the brain has already consumed the nutrients, that is, the veins. Thus, this layer of the meninges plays an important role in making a good part of the central nervous system function as it should and be able to evacuate excess blood.
However, this function of the dura mater also exposes it to risks in the form of pathologies, such as very dangerous aneurysms, infections such as meningitis or ischemia.
5. Perception of pain and brain tension
Both the dura mater and the rest of the meninges are innervated by different nerves, containing a large number of receptors. These receptors are a mechanism for physiological detection of brain problems For example, they allow us to perceive the pain associated with the pressure of the brain against the skull, and they are even mainly responsible for us suffering from headaches.
This function is especially vital for survival, given that the brain itself does not have receptors that can warn of the occurrence of an internal illness. In other words, without the presence of meninges we would not be able to detect headaches that can cause us warn of problems and give us time to react shortly before very delicate areas of the nervous system are damaged.
