When it begins to develop, the central nervous system is made up of three sections: the forebrain, midbrain, and hindbrain. Later, these initial structures will give rise to different parts of the adult brain, including the diencephalon.
In this article we will describe the structure and functions of the diencephalon, Which encompasses regions as important as the thalamus and hypothalamus and enables the proper functioning of multiple biological processes, such as the secretion of hormones and the regulation of the autonomic system.
What is the diencephalon?
The diencephalon is a part of the brain located in its medial region. This name refers to the part of the neural tube that gives rise to various brain structures as embryonic development progresses.
More precisely, once differentiated, the main parts of the diencephalon are the thalamus, hypothalamus, epithelium, subthalamus and retina. Likewise, the pituitary or pituitary gland is attached to the hypothalamus and the optic nerve also connects to the diencephalon.
The cavity formed by these structures is the third ventricle, Which cushions the effects of trauma that could damage them. The posterior cerebral artery and the Willis polygon provide blood supply to the diencephalon.
Parts of the brain and brain
The brain is the part of the central nervous system that is located in the cranial cavity, as opposed to the spinal cord. This organ is made up of the brain, cerebellum and brainstem.
The diencephalon develops from the forebrain or forebrain, one of the three parts of the brain during the early embryonic development of the nervous system. The other two initial sections are the midbrain, which will connect the different parts of the brain, and the hindbrain, which will give rise to the cerebellum, medulla oblongata and bulge.
As the fetus grows the forebrain is divided into diencephalon and telencephalon; from there, the cerebral hemispheres, basal ganglia, and the limbic system, including the amygdala, will develop. We describe the sections of the diencephalon in the next section.
Structure and functions of the brain
The region of the brain that we know as the diencephalon is made up of several structures. These are connected to each other and to the rest of the nervous system, both cortically and subcortically.
Its relationship with the endocrine system, which is made up of glands that secrete hormones into the blood, is also very relevant.
The thalamus functions as a kind of raised core for connections between cerebral cortex and subcortical structures. It is essential for the reception of sensory afferents (except olfactory ones, which go directly to the cortex) and their transmission to the cerebral lobes.
This structure also plays a role in the regulation of consciousness and the sleep-wake cycle and influences motor skills through the efferents that project from the thalamus to the basal ganglia and the cerebellum.
The hypothalamus is located below the thalamus. The main functions of this structure include connect the nervous and endocrine systems and control the secretion of hormones by the pituitary and other glands.
The hypothalamus directly produces vasopressin and oxytocin, but also stimulates the endocrine glands as they secrete other hormones. It is also essential for regulating homeostasis in the body as it is involved in thirst, hunger, temperature, circadian rhythms, stress, and other bodily processes.
3. Pituitary gland or pituitary gland
The pituitary gland is an endocrine gland attached to the hypothalamus. It is very important for growth, kidney regulation, sexual function and reproduction, among other aspects.
It consists of two lobes: the anterior pituitary (adenohypophysis) and the posterior (neurohypophysis). While the neurohypophysis secretes oxytocin and vasopressin, synthesized by the hypothalamus, the adenohypophysis produces and releases corticotropin, growth hormone, prolactin, luteinizing hormone and luteinizing hormone. follicle stimulating hormone, among others.
This brain structure it is mainly composed of the pineal gland, Fundamental in circadian and seasonal cycles, and avenule, involved in the function of the neurotransmitters dopamine, norepinephrine and serotonin. The epithelium connects the limbic system with other areas of the brain.
The subthalamus is attached to the pale globe, one of the main nuclei of the basal ganglia. As a result, it plays a regulatory role in extrapyramidal and involuntary movements.
6. Retina and optic nerves
The retina develops from the diencephalon, so it is considered to be part of the central nervous system. The optic nerve allows the transmission of information from the eye to the brain by connecting it to the diencephalon.
7. Third ventricle
The cerebral ventricles they allow the circulation of cerebrospinal fluid, Which performs functions similar to those of the blood in the brain and spinal cord, in addition to protecting neural tissue from injury and injury. The third ventricle is found in the middle part of the ventricular system, below the epithelium.