Neck bones consist of seven cervical vertebrae, which include the upper part of the spine. Large muscles that influence the shape of the neck are the trapezius muscle in the back and the sternomastoideus muscle in the front. They run from the back of the ear down to the inner ends of the clavicles.
Neck able to move in all directions: Tilt your head back and forth, sideways to either shoulder, and rotate it from side to side 180 degrees.
Apart from the sound-conducting structures in the ears, only the jaw moves from the joints of the head. All other bones of the skull are rigidly linked and immovable.
The muscles of the face can be conditionally divided into two types:
The proportions of the human head. Simple construction method
The face is, of course, the most expressive part of the body. Here simple construction method which will help you see which simple shapes head consists. Average proportions human head shown in the figure below. The height of the head is about the same as its width when viewed from the side, so in profile it fits into a square. Seen from the front, the width of the head is much less than its height.. 
Start by drawing the head in profile. Draw a circle for the skull and then add two lines on the front of the face to represent the jaw as shown in the image above. 
The most common rookie mistake when depicting the head is that head looks flat. Therefore, as soon as possible, try to draw three-quarter view of the head, trying to display the roundness and solidity of the forms. Use light reference lines to indicate the center line of the face and the position of the eyes. 
The figure shows a rather spineless face, but at this stage the main thing is to understand the basic forms. People's faces differ from the average in many ways, which will be discussed in detail in the following lessons. These drawings represent the first step. If you draw hundreds of these simplified heads, you will come to understand all the subtleties of the relief. human face and be able to fill your drawings with life and character.
The most important thing to understand is that the face is not just a flat surface with details superimposed on it. To draw faces successfully, you must understand three-dimensional shape surfaces - that's why we started with a spineless average face that can belong to both a man and a woman. 
If you look at the hazy newspaper photo of the crowd below, you will see that each face differs from the rest only in the display of light and shadow on it, and not in the shape of the eyes or lips. If you can imagine face as a pattern, in this case you will avoid the common mistake of creating lifeless mechanisms of eyes, noses and mouths, indistinguishable from each other. 
That's why practice drawing the face template with the addition of light and shadow until you fully understand its shape. 
The images above show several basic face and head shapes under different angle. Once again, it is important now that you understood real shape surfaces and not just a plan.
The article used materials from the book Ron Tiner "Figure Drawing without a model".
Many guys had to make unexpected surprises to their lovers. One of the unforeseen surprises can be considered a portrait of his beloved girl, made by himself, and the process of working on it filmed on video. But how to draw a girl's head in stages, conveying all the subtleties of the face, emotions, look? Some believe that only professional artists can do such work, but if you show desire and patience, study the basic proportions and rules for building a face, you can make a good drawing yourself. Well, let's try to figure out how to draw a head with a pencil in stages.
So, what do you need to know to draw a person's head in stages? Portrait of a girl or a guy - complex view art, so you need to start it by studying the stages of work. Professional Artists It is advised to first study the following tips:
Main contour and center lines
The initial contour of the face - main stage in the correct image of a portrait of a person. The head drawn in pencil begins with an oval face. No matter how strange it may sound, but the beginning of this oval should be a circle. To do this, in the center of the picture, you need to put a point along which the orientation of the further picture is carried out.
You can use a compass to make a circle of the desired radius from a given point. Then a straight line down is drawn from it, crossing the bend of the circle for the same length as before it. This will be the extreme point of the jaw. Lightly pressing on the pencil, you should make the correct oval: on top - rounded, on the bottom - pointed. Its shape can be different, because the face is round, elongated or bony.
Those who want to learn how to draw a head in stages with a pencil need to learn how to apply centerlines on an oval (make a sketch). They help the correct construction of the face, its proportions. First, a line is drawn horizontally in the center, dividing the pattern in half. Then each of the resulting halves is divided in parallel even in half. In the middle of the oval, a vertical axis is drawn along the face. You get a kind of grid of 8 branches.
Expressive eyes - the basis of the picture
A novice artist should know that the eyes are depicted in the middle of the oval (head). The eyes will be placed on the central horizontal axis. What should be the distance between them and the width? To do this, this axis must be divided into 8 equal intervals. It is important to remember that the distance between the eyes should correspond to one more eye. Therefore, from the central point to the left and right, we retreat one gap at a time, we begin to draw the eyes, each of which will occupy the next two gaps. The width of each eye will correspond to 2/8 of the center line. The main thing is that they are not too close to each other or too far (it is important to choose the middle, you can do without a grid).
With the help of the eyes, the expressiveness of the face is transmitted, so it is important to accurately draw their shape and position them correctly. You should start the image by drawing the lower and upper eyelids. It is necessary to clearly highlight the corners of the eyes. Above upper eyelid you need to depict the palpebral groove in the form of an arc, also repeat from below, only smaller. great attention should be given to the eyeball (iris and pupil). The look will be expressive if the pupils are directed in one direction. Here are some nuances of the image of the eyes:
Draw the nose
Let's try to understand further how to draw a head in stages. After the contours of the eyes, you should move on to the shape of the nose. Where should it be located? The height of the nose should correspond to the size of the central and lower horizontal lines. The width starts from the corners of the eyes. From them, carefully draw lines down to the line, above which we draw three circles. They will help to more accurately depict the nostrils, wings of the nose and the central part. Focusing on this basis, we begin to make an accurate drawing of the nose.
Eyebrow and hair highlighting
Further, the drawing begins to acquire a more detailed image. Having made the bridge of the nose, let's try to move on to neat eyebrows. To do this, the picture can be flipped horizontally. It is important to know that it is better to start the image of the eyebrows from a point closer to the nose. The correct height of the eyebrow above the level of the eye should correspond to one more eye.
After the outlines of the shape of the eyebrows are made, we will apply strokes resembling hairs. Near the nose, they will turn out to be wider and thicker, and towards the end - thinner and sparse.
After drawing the eyebrows, you need to move on to the hair. Here everything will depend on the hairstyle.
The correct outlines of the lips and face
The next element to sketch is the lips or mouth. How to properly position it. Everything is simple. It should be in the center of the lowest part of the grid, under the nose. To determine its horizontal length, draw two lines down from the irises of the eyes, this will be the width of the company. In the marked place we will try to draw neat lips. The bottom one is easier to draw, so it's best to start with it. We simply copy the top one along the bottom one, just divide it in half. Some girls have plump lips, others have thinned ones, you can navigate from the photo.
To complete the sketch, you need to clearly draw the outlines of the face. To do this, you can highlight the cheekbones a little.
Ear position
The shape and position of the ears also need to be given due attention. The height of the ear is approximately equal to the height of the nose. The ear consists of 5 parts: lobe, helix, antihelix, tragus, antitragus. To begin with, we depict the auricle ( general form). Then draw a C-shaped curl. With the help of shadows and light we make the inner part of the ear.
Working on details and shadows
Now we erase the grid lines, we got the initial one. Further work is to decorate and add shadows. The face needs to be more specific. Cheekbones and the shape of the chin play an important role here. It is important not to turn a girl into a man whose chin is stronger.
How to draw a head in stages with a pencil, like real artists? For this we need soft pencil, with which we will apply shadows that give volume to the face. Contrasts and shadows can highlight the desired parts of the portrait, for this you need to determine the darker and lighter places. First, you can simply circle them, then start shading. After that, the hatching can be shaded with a piece of paper in right places. Straight strokes will make the drawing angular and hard.
Finishing touches
The girl's face requires special attention, as it is decorated with hair (hairstyle). It should look natural and suitable for this type of face. Beautiful flowing hair adorn female image. You can also add part of the shoulders and neck to it.
The highlight of each drawing is facial expressions and depiction of emotions. This can be done with eyebrows. One has only to raise or lower them a little - the face will sparkle with new colors. The upturned inner corners of the eyes will help portray sadness, sometimes even crying face. A more embittered person can be depicted by bringing the eyebrows to the bridge of the nose.
Facial expressions can also be drawn by darkening the iris of the eyes and raising the corners of the lips. The darker the pupil, the more expressive the look. From the first time it is difficult to draw a smile on the face, but even a small raising of the corners of the lips makes the girl cute. Facial expressions help to express the character of a person. It is important to remember that you need to constantly train your skills, then facial expressions and emotions of a person will be more accurately obtained.
The brain is the main regulator of the functions of any living organism, one of the elements Until now, medical scientists have been studying the features of the brain and discovering its new incredible possibilities. This is a very complex organ that connects our body with the external environment. The parts of the brain and their functions regulate all life processes. External receptors catch signals and inform any part of the brain about incoming stimuli (light, sound, tactile, and many others). The response is immediate. Let's take a closer look at how our head "processor" works.
General description of the brain
The brain regions and their functions completely control our life processes. Consists human brain out of 25 billion neurons. This incredible number of cells forms the gray matter. The brain covers several layers:
- soft;
- hard;
- arachnoid (cerebrospinal fluid circulates here).
Liquor is a cerebrospinal fluid, in the brain it plays the role of a shock absorber, a protector from any impact force.
In both men and women, the brain is developed in exactly the same way, although its weight is different. More recently, the debate has subsided that the weight of the brain plays some role in mental development and intellectual abilities. The conclusion is unambiguous - it is not. The weight of the brain is approximately 2% of the total mass of a person. In men, its average weight is 1,370 g, and in women - 1,240 g. The functions of the parts of the human brain are developed in a standard way, vital activity depends on them. Mental capacity depend on the quantitative connections created in the brain. Each brain cell is a neuron that generates and transmits impulses.
The cavities inside the brain are called ventricles. The cranial paired nerves go to different departments.
Functions of the brain regions (table)
Every part of the brain has a job to do. The table below clearly demonstrates this. The brain, like a computer, clearly performs its tasks, receiving commands from the outside world.
The functions of the brain regions, the table reveals schematically and succinctly.
Let's take a closer look at the parts of the brain below.
Structure
The picture shows how the brain works. Despite this, the most significant part is occupied by all parts of the brain and their functions play a huge role in the functioning of the body. There are five main divisions:
- final (of the total mass is 80%);
- posterior (bridge and cerebellum);
- intermediate;
- oblong;
- average.
At the same time, the brain is divided into three main parts: the brain stem, the cerebellum, and the two cerebral hemispheres.
telencephalon
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 study their structure closely.
The telencephalon stretches from the frontal to the occipital bone. Two cerebral hemispheres are considered here: left and right. This section is different from others. largest number furrows and convolutions. The development and structure of the brain are closely linked. Experts have identified three types of bark:
- ancient (with olfactory tubercle, anterior perforated substance, semilunar subcallosal and lateral subcallosal gyrus);
- old (with dentate gyrus - fascia and hippocampus);
- new (represents the rest of the cortex).
The hemispheres are separated by a longitudinal groove, in its depths there is a vault and a corpus callosum, which connect the hemispheres. The corpus callosum itself is lined and belongs to the neocortex. The structure of the hemispheres is quite complex and resembles multilevel system. Here, the frontal, temporal, parietal and occipital lobes, subcortex and cortex are distinguished. The large hemispheres perform a huge number of functions. It is worth noting that left hemisphere commands the right side of the body, and the right, on the contrary, the left.
Bark
The surface layer of the brain is the cortex, it has a thickness of 3 mm, covers the hemispheres. The structure is made up 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. The building has six layers:
- external pyramidal;
- external granular;
- internal granular;
- molecular;
- internal pyramidal;
- with spindle 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 controls several specific bodily functions. Each share is responsible for its own parameters. Let's take a closer look at the functions associated with hotels:
- temporal - controls the sense of smell and hearing;
- parietal - responsible for taste and touch;
- occipital - vision;
- frontal - complex thinking, movement and speech.
Each neuron contacts other neurons, there are up to ten thousand contacts (gray matter). Nerve fibers are white matter. Some part unites the hemispheres of the brain. White matter includes three types of fibers:
- association links connect different cortical areas in one hemisphere;
- commissural connect the hemispheres to each other;
- projection ones communicate with lower formations, have paths of analyzers.
Considering the structure and functions of the brain, it is necessary to emphasize the role of gray and white matter. The hemispheres inside have (gray matter), their main function is the transmission of information. The white matter is located between the cerebral cortex and the basal ganglia. There are four parts here:
- between furrows in convolutions;
- in the outer 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 connects the cortex of the convolutions with the underlying sections. form the subcortex of the brain.
The telencephalon - manages all the vital functions of the body, as well as the intellectual abilities of a person.
diencephalon
The brain regions and their functions (table above) include the diencephalon. If you look in more detail, it is worth saying that it consists of ventral and dorsal parts. The hypothalamus belongs to the ventral, and the thalamus, metathalamus, and epithalamus to the dorsal.
The thalamus is a mediator that directs the received irritations to the hemispheres. It is often referred to as the "optic tubercle". It helps the body quickly adapt to changes in external environment. The thalamus is connected to the cerebellum via the limbic system.
The hypothalamus controls autonomic functions. Influence comes through nervous system, and, of course, the endocrine glands. Regulates the work of the endocrine glands, controls metabolism. The pituitary gland is located directly below it. regulates body temperature, cardiovascular digestive system. The hypothalamus also controls our eating and drinking behavior, regulates wakefulness and sleep.
Rear
The hindbrain includes the pons located in front and the cerebellum, which is located behind. Studying the structure and functions of the parts of the brain, let's take a closer look at the structure of the bridge: the dorsal surface is covered by the cerebellum, the ventral one is represented by a fibrous structure. The fibers are directed transversely in this section. On each side of the bridge, they depart to the cerebellar middle peduncle. In appearance, the bridge resembles a thickened white roller located above the medulla oblongata. The nerve roots exit into the bulbar pontine groove.
The structure of the posterior bridge: on the frontal section, it can be seen that the department of the anterior (large ventral) and posterior (small dorsal) parts consists. Between them, the trapezoid body serves as a boundary, the transverse thick fibers of which are considered to be the auditory pathway. Conductor 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. The cerebellum is often referred to as the "small brain". It occupies the posterior cranial fossa, covers the rhomboid. The mass of the cerebellum is from 130 to 160 g. large hemispheres, which are separated by a transverse slit. The lower part of the cerebellum is adjacent to the medulla oblongata.
Two hemispheres are distinguished here, the lower, upper surface and the worm. The boundary between them is called a horizontal deep slit. A lot of cracks cut the surface of the cerebellum, between them there are thin convolutions (rollers). Between the grooves there are groups of convolutions, divided into lobules, they represent the lobes of the cerebellum (posterior, flocculent-nodular, anterior).
The cerebellum contains both grey, and gray is located on the periphery, forming a cortex with molecular and pear-shaped neurons, and a granular layer. Under the cortex there is a white substance that penetrates into the gyrus. In the white matter there are blotches of gray (its nuclei). In cross section, 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 the regulator of the coordination of the movements of our body.
midbrain
The midbrain is located in anterior section bridge and goes to the papillary bodies, as well as to the visual tracts. Here clusters of nuclei are distinguished, which are called tubercles of the quadrigemina. The structure and functions of the brain regions (table) indicate that this department is responsible for latent vision, the orienting reflex, gives orientation to reflexes to visual and sound stimuli, and also maintains muscle tone in the human body.
medulla oblongata: brainstem
The medulla oblongata is a natural extension spinal cord. That is why the structure has a lot in common. This becomes especially clear if we examine the white matter in detail. It is represented by short and long nerve fibers. In the form of nuclei, gray matter is represented here. Parts of the brain and their functions (table presented above) indicates that medulla controls our balance, coordination, regulates metabolism, controls breathing and blood circulation. It is also responsible for such important reflexes of our body as sneezing and coughing, vomiting.
The brain stem is divided into the hindbrain and midbrain. The trunk is called the middle, oblong, bridge and diencephalon. Its structure is 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.
This organ of man (and animals), perhaps, can be called the main one. While the heart
performs a simple function- to pump blood, the brain has a much greater responsibility: to think,
develop, save the owner. The brain provides a person with thinking and is extremely complex
mechanism, which we cannot yet fully understand. Neurosurgeons around the world are struggling with
the most difficult tasks of understanding the work of gray matter, and in this area there is
steady progress. Nevertheless, it has not yet been possible to transplant a person's head (and the brain, therefore)
Anyone who has ever abused alcohol or cigarettes at least once knows that getting rid of this kind of addiction can sometimes be extremely difficult. Unfortunately, cravings for harmful substances cannot yet be simply turned off with the push of a button, but researchers at Scripps Research Medical Center are a little closer to creating such a device. They found that by targeting a specific area of the brain with a laser, they could curb the urge to drink alcohol and even eliminate trembling. The technology really works, and this has been proven in an experiment with alcohol-addicted rats.
Although the term " neural network» can be applied to both the anatomical structure and computing system, these neural networks still have more differences than similarities. And first of all, this is due to the extremely complex structure of the neural plexuses of the brain. But everything can change thanks to the development of scientists from the National Institute of Standards and Technology. Their invention can become a new stage in the development of technology for building neural networks.
