Hypothalamus: Definition, Characteristics And Functions
The most characteristic part of the brain is its surface full of folds and cracks, but beneath this layer of cells there are many other brain structures without which we would not be able to think or adapt to the environment. Some of them, like the cerebellum, are more or less known because they ultimately stand out and are easy to see, but others are much more hidden, like the hypothalamus
Of course, the fact that the hypothalamus is small and much more inconspicuous than other parts of the brain does not give us any idea about its importance. The role that the hypothalamus plays in our survival is of utmost importance because, among other things, it is responsible for coordinating and communicating two apparently independent worlds: that of neurons and that of the hormones that navigate our blood.
The hypothalamus is, along with the thalamus, one of the parts of a brain structure called the diencephalon which is located in the center of the brain in humans, below the cerebral cortex and above the brain stem.
Its name is a direct reference to the place it occupies: “hypothalamus” literally means “below the thalamus.” Indeed, if we look at the drawing of a sagittal section of the human brain We will see that the hypothalamus seems to be the saddle of the thalamus, which is much more voluminous
The hypothalamus is one of the brain structures with a most important role in regulating moods body temperature, sleep, sexual impulses and hunger and thirst.
Due to its relationship with the regulation of emotions and physiological states, the hypothalamus is considered to be part of the limbic system, the set of parts of the brain directly related to the generation of emotions. It can be said that the hypothalamus is responsible for launching and coordinating many of the processes that allow us to survive and adapt to changing situations.
Furthermore, the hypothalamus is located near the brain stem because it intervenes in the basic functions that guarantee our survival and that, therefore, are carried out involuntarily, without us realizing it. In addition to acting as a bridge between the brain and the endocrine system, coordinates everything that is done through the autonomic nervous system that is, the one that sends orders to parts of the body so that they adapt to each situation.
Among the processes that the hypothalamus is responsible for regulating are:
A vital process: homeostasis
The hypothalamus is constantly receiving information from all parts of the body and sending orders accordingly, because Its task is to ensure that nothing that happens inside the organism breaks the balance of how the entire body should function That is why it works as a mediator of different parts of the body, whether or not they are in contact with the brain; to influence the most distant parts, it allows hormones to be released into the blood that reach their destination in a matter of minutes to trigger the necessary process.
For example, if we see something that could be potentially dangerous, the hypothalamus will ensure that everything that happens in the body works coherently, preparing to react quickly. It will not let the heart start beating rapidly without many other organs acting accordingly: the muscles will tense, the amount of energy available in the blood will increase, etc.
In the same way, if we have not eaten for a long time, the hypothalamus will cause the neurons of the limbic system to generate dynamics that make the sensation of hunger appear, while at the same time it will intervene in the way in which fats and sugars available in the body are burned. All of this at the same time, so that there is always a balance and the property of homeostasis is maintained that is, the ability to maintain stability in the functioning of things.
The hypothalamus and its connection with the pituitary gland
The fact that the hypothalamus is involved in the regulation of many vital functions means that it must be able to send orders that reach very different parts of the body. Furthermore, some of the effects it has to produce must be more or less instantaneous, while others appear with a delay and remain active for longer.
How does the hypothalamus manage to be able to cover this entire range of responsibilities? Well acting as a hinge between the nervous system and the endocrine system As the hypothalamus is inserted in a very well-connected place in the brain (it is very close to its center), its connection with the rest of the nervous system is very easy, but it also connects with the endocrine system through a small structure called hypophysis or pituitary gland.
The pituitary gland is located just below the hypothalamus, and is very well connected to it, which is why He is dedicated to executing the orders that he passes to him: Basically, it causes hormones to be released. The hypothalamus crosses data from the nervous system with those received about the quantity and type of hormones that are circulating in the blood.
When it detects an imbalance, it causes the pituitary gland to secrete certain hormones that will be introduced into the bloodstream and will either alter the functioning of certain organs or cause other parts of the body to secrete other hormones in turn. In this way, the necessary biological processes will be adjusted to improve the chances of survival.
Since the hypothalamus has effects on both the brain and many other parts of the body that They react to the presence of hormones in the blood its effects are noticeable both in a matter of milliseconds and minutes.
