The brain is the main regulator of the functions of any living organism, one of the elements of the central nervous system. Until now, medical scientists are studying the features of the brain and discovering new and incredible possibilities. This is a very complex organ that connects our body with the environment. The brain departments and their functions regulate all life processes. External receptors pick up signals and inform any section of the brain about incoming stimuli (light, sound, tactile, and many others). The response comes instantly. How our head "processor" works, we’ll understand in more detail.
General description of the brain
The departments of the brain and their functions completely guide our life processes. The human brain consists of 25 billion neurons. This incredible number of cells forms gray matter. The brain covers several shells:
- soft;
- solid;
- spider web (cerebrospinal fluid circulates here).
Liquor is a cerebrospinal fluid, in the brain it plays the role of a shock absorber, a protector against any shock force.
In both men and women, the brain is developed in exactly the same way, although its weight is different. More recently, the debate that brain weight plays a role in mental development and intellectual abilities has subsided. The conclusion is unequivocal - this is not so. The weight of the brain is approximately 2% of the total human mass. In men, its average weight is 1,370 g, and in women - 1,240 g. The functions of the human brain are developed standardly, and vital activity depends on them. Mental abilities depend on the quantitative connections created in the brain. Each brain cell is a neuron that generates and transmits impulses.
Cavities inside the brain are called ventricles. The cranial paired nerves go to different departments.
Functions of the brain (table)
Each department in the brain does its job. The table below illustrates this. The brain, like a computer, clearly performs its tasks, receiving commands from the outside world.
The functions of the departments of the brain, the table reveals schematically and capaciously.
Below we consider the parts of the brain in more detail.
Structure
The picture shows how the brain works. The largest part is occupied by the cerebral hemispheres, despite this, all parts of the brain and their functions play a huge role in the body. There are five major departments:
- final (of the total mass is 80%);
- back (bridge and cerebellum);
- intermediate;
- oblong;
- middle.
At the same time, the brain is divided into three main parts: the brain stem, cerebellum, two large hemispheres.
End brain
It is impossible to briefly describe the structure of the brain. To understand the parts of the brain and their functions, it is necessary to closely study their structure.
The final brain extends from the frontal to the occipital bone. Two large hemispheres are considered here: left and right. From others, this department is distinguished by the largest number of furrows and convolutions. The development and structure of the brain are closely linked. Specialists identified three types of bark:
- ancient (with an olfactory tubercle, anterior perforated substance, lunate podzolosnoy and lateral podzolosnoy gyrus);
- old (with dentate gyrus - fascia and hippocampus);
- new (represents the rest of the cortex).
The hemispheres are separated by a longitudinal furrow, in its depth is the arch and the corpus callosum, which connect the hemispheres. The corpus callosum itself is lined with nerve fibers and belongs to the new cortex. The structure of the hemispheres is quite complex and resembles a multi-level system. Here, the frontal, temporal, parietal and occipital lobes, subcortex and cortex are distinguished. The cerebral hemispheres perform a huge number of functions. It is worth noting that the left hemisphere commands the right side of the body, and the right, on the contrary, commands the left.
Bark
The surface layer of the brain is the cortex, it has a thickness of 3 mm, covers the hemispheres. The structure consists of vertical nerve cells having processes. The cortex also contains efferent and afferent nerve fibers, as well as neuroglia. The parts of the brain and their functions are discussed in the table, but what is the cortex? Its complex structure has horizontal layering. There are six layers in the structure:
- outer pyramidal;
- external granular;
- internal granular;
- molecular;
- internal pyramidal;
- with fusiform cells.
Each has a different width, density, shape of neurons. Vertical bundles of nerve fibers give the cortex a vertical striation. The area of the cortex is approximately 2,200 square centimeters; the number of neurons here reaches ten billion.
Parts of the brain and their functions: cortex
The cortex directs several specific functions of the body. Each share is responsible for its parameters. Consider the functions associated with calving in more detail:
- temporal - controls the sense of smell and hearing;
- parietal - is responsible for taste and touch;
- occipital - vision;
- frontal - complex thinking, movement and speech.
Each neuron is in contact with other neurons, there are up to ten thousand contacts (gray matter). Nerve fibers are a white matter. A certain part unites the hemispheres of the brain. White matter includes three types of fibers:
- associative link different cortical sites in one hemisphere;
- commissural connect the hemispheres with each other;
- projection ones communicate with lower formations, have analyzer paths.
Considering the structure and functions of the departments of the brain, it is necessary to emphasize the role of gray and white matter. The hemispheres inside have basal ganglia (gray matter), their main function is to transmit information. Between the cerebral cortex and the basal nuclei is white matter. Four parts are distinguished here:
- between the furrows in the convolutions;
- in external places of the hemispheres;
- included in the inner capsule;
- located in the corpus callosum.
The white matter located here is formed by nerve fibers and binds the crust of the gyrus with the underlying departments. The subcortical nuclei form the subcortex of the brain.
The final brain - governs all the vital functions of the body, as well as the intellectual abilities of a person.
Diencephalon
Parts of the brain and their functions (the table is presented above) include the diencephalon. If you look in more detail, it is worth saying that it consists of the ventral and dorsal parts. The hypothalamus belongs to the ventral, the thalamus, metatalamus, and also the epithalamus to the dorsal.
The thalamus is a mediator that directs the resulting irritation to the hemispheres. Often it is called the "visual hillock." It helps the body quickly adapt to changes in the external environment. The thalamus is connected to the cerebellum via the limbic system.
The hypothalamus directs autonomic functions. The effect goes through the nervous system, and, of course, the endocrine glands. Regulates the endocrine glands, controls metabolism. The pituitary gland is located directly below it. Regulated body temperature, cardiovascular and digestive systems. The hypothalamus also directs our eating and drinking behavior, regulates wakefulness and sleep.
Rear
The hindbrain includes the anterior bridge and the cerebellum, which is located behind. Studying the structure and functions of the departments of the brain, we will take a closer look at the structure of the bridge: the dorsal surface is blocked by the cerebellum, the ventral surface is represented by the fibrous structure. The fibers are directed laterally in this section. On each side of the bridge they extend to the cerebellar middle leg. In appearance, the bridge resembles a thickened white cushion located above the medulla oblongata. Roots of nerves go into the bulbar-bridge furrow.
The structure of the rear axle: on the frontal section shows that there is a division of the anterior (large ventral) and posterior (small dorsal) parts. Between them, the trapezoid body serves as the border, the transverse thick fibers of which are assigned to the auditory pathway. Conduction function is completely dependent on the hindbrain.
Cerebellum (small brain)
The table “Department of the brain, structure, functions” indicates that the cerebellum is responsible for the coordination and movement of the body. This department is located behind the bridge. Often the cerebellum is called the "small brain." He occupies the posterior cranial fossa, covers the diamond-shaped. The mass of the cerebellum is from 130 to 160 g. There are large hemispheres located above, which are separated by a transverse fissure. The lower part of the cerebellum is adjacent to the medulla oblongata.
Two hemispheres, the lower, upper surface and the worm, are distinguished here. The border between them is called a horizontal deep gap. Many slits cut the surface of the cerebellum, between them there are thin convolutions (ridges). Between the grooves are groups of convolutions, divided into lobules, they represent the cerebellar lobes (posterior, rag-nodular, anterior).
The cerebellum contains both gray and white matter. Gray is located on the periphery, forms a cortex with molecular and pear-shaped neurons, and a granular layer. Under the bark there is a white substance that penetrates the gyrus. In white matter there are inclusions of gray (its nuclei). In the context, this ratio is similar to a tree. Those who know the structure of the human brain, the functions of its departments, will easily answer that the cerebellum is a regulator of the coordination of movements of our body.
Midbrain
The midbrain is located in the anterior region of the bridge and goes to the papillary bodies, as well as to the optic tracts. Here clusters of nuclei are identified, which are called hillocks of the quadruple. The structure and functions of the departments of the brain (table) indicate that this department is responsible for blind vision, orientational reflex, gives orientation to the reflexes of visual and sound stimuli, and also supports muscle tone of the human body.
Medulla oblongata: stem
The medulla oblongata is a natural extension of the spinal cord. That is why the structure has a lot in common. This becomes especially clear if we examine in detail the white matter. Its short and long nerve fibers represent. In the form of nuclei, gray matter is represented here. The departments of the brain and their functions (the table is presented above) indicate that the medulla oblongata directs our balance, coordination, regulates metabolism, directs respiration and blood circulation. He is also responsible for such important reflexes of our body as sneezing and coughing, vomiting.
The stem part of the brain is divided into the hind and midbrain. The trunk is the middle, oblong, bridge and diencephalon. Its structure is the descending and ascending paths connecting the trunk with the spinal cord and brain. In this part, control over the heartbeat, breathing, articulate speech is carried out.