The diencephalon is the largest and most functionally significant part of the brain stem. It contains a huge number of nuclei, which are very important centers of the autonomic system, as well as two endocrine glands - the pineal gland and the pituitary gland. The diencephalon is located under the corpus callosum itself between the cerebral hemispheres, at the back it is limited by the optic tract and posterior perforated substance, and in front by the visual cross.
The structure of the diencephalon is complex, since it contains a large number of different centers that regulate the normal functioning and proper functioning of various organs and systems. In the brain (intermediate) there are: epithalamus, thalamus, metatalamus, hypothalamus and third ventricle.
The thalamus (optic tubercles) is a paired formation of an oblong shape. It is formed by the accumulation of gray matter in the form of nuclei (about forty), which are separated by a layer of white matter. The epithalamus is represented by the pineal gland or pineal gland. The pineal gland in appearance resembles a spruce cone and is localized above the quadruple of the midbrain. On the outside, it is covered with a capsule, from which the septum departs inward, dividing the pineal gland into lobules.
The metalamus is represented by medial and, of course, lateral cranked bodies, which are the centers of hearing and vision. They are located behind the pillow of the two parts of the thalamus and are connected to the midbrain with the legs of the upper diode and the lower. The hypothalamus is represented by a funnel, an optic cross, a gray tubercle, the pituitary gland and two mastoid bodies. The pituitary gland is the central gland of the endocrine system located in the pituitary fossa of the Turkish saddle on the sphenoid bone. The hypothalamus forms precisely the lower part of the intermediate brain.
All hypothalamic nuclei, of which about forty, are additionally divided into posterior, intermediate, and anterior by their location; most of them produce a neurosecret. The anterior nuclei are paraventicular and supraoptical, the posterior ones are the hypothalamic and mastoid nuclei, the middle ones are the lower and upper medial hypothalamic nuclei, the funnel nuclei and the sulfur-tuberous ones.
The diencephalon is also represented by the third ventricle, which is the brain cavity. It communicates below the fourth ventricle, back and front - through the interventricular opening - with the first and second ventricles. As in all the others, in the third are the vascular plexuses that produce cerebrospinal fluid.
The functions of the diencephalon depend on its departments:
- Regulation of the endocrine system, as the pituitary and pineal gland are located in the diencephalon. The pituitary gland stimulates the production of the following hormones: growth, prolactin (the ability to form milk in the alveoli of the mammary glands), TSH, ACTH, follicle-stimulating, luteinizing, luteotropic, melanotropin, oxytocin, vasopressin. The neurosecretory function of the pineal gland has a clear daily regimen. It synthesizes melatoxin at night, which is involved in pigment metabolism, and during the day - serotoxin.
- Regulation of the autonomic system. In the hypothalamus there are subcortical centers of vegetative reflexes, such as thirst, hunger, satiety, pleasure, displeasure, thermoregulation, as well as all kinds of feelings.
- Subcortical centers of vision are located in the lateral cranked bodies, and in the medial - hearing.
- The thalamus is the center of general sensitivity besides olfactory.
The diencephalon, as a rule, has many functions, in case of violation of at least one of them, irreparable consequences can occur that will inevitably lead to disability or death.