The human sense of smell. Functions of the olfactory organ
Very important for all of us are the senses. The sense of smell of a person can make the perception of the world much brighter.
The role of the sense of smell
The sense of smell is the nose, which serves us so that we can enjoy wonderful smells and aromas. He also warns us about various dangers (fire, gas leak). Good sense of smell is very important for any person, because without it it is impossible to perceive the world 100%. So, with a bad sense of smell, life can become gray and dull, devoid of all color.
The organ of smell is a tool for obtaining information, it helps a person to know the world. It is known that children whose perception of smells is impaired cannot develop properly and lag behind their peers. The sense of smell of a person is closely connected with the organ of taste. Just a small loss of the ability to subtly feel and distinguish odors negates the pleasure of the most delicious food.Yes, and their surroundings, people often choose by smell. Probably no one will be able to communicate with a person for a long time if his scent is not very pleasant.
The sense of smell, helping us to perceive odors, is able to create a mood and influence our well-being. For example, the smells of cinnamon and mint can increase attention and reduce irritability, and the aromas of coffee and lemon help clear thinking. The sense of smell of a person has the ability to distinguish up to 10,000 flavors. This wealth, given to us by nature, needs to be cherished. None of the people wants to stop smelling flowers, herbs, woods, the sea.
What is the sense of smell?
The ability to distinguish and perceive different odors of substances that are in the environment is the sense of smell. Recognition of smells usually provokes the emergence of various emotions. In this sense, the sense of smell often becomes more important than, for example, good hearing or excellent vision. The effect of various aromatic substances on the organ of smell can excite the human nervous system. This, in turn, leads to a change in the functions of various organs and systems of the whole organism.
The sense of smell is the nose, which perceives the corresponding stimuli dissolved in the air. The olfactory process consists of:
- olfactory mucosa;
- olfactory thread;
- olfactory bulb;
- olfactory tract;
- cerebral cortex.
The olfactory nerve and receptor cells are responsible for the perception of odors. They are located on the olfactory epithelium, which is located on the mucous membrane of the upper-rear part of the nasal cavity, in the nasal septum and upper nasal passage. In humans, the olfactory epithelium covers an area of about 4 cm2.
All signals from the receptor cells of the nose (of which there are up to 10 million) through the nerve fibers enter the brain. There is formed the idea of the nature of the smell or its recognition occurs.
In humans, there are olfactory and trigeminal nerves, to the end of which are attached smell receptors. Nerve cells have two types of processes. The short ones, called dendrites, are shaped like sticks, each of which contains 10-15 olfactory cilia. Other, central processes (axons) are much thinner, they form thin nerves that resemble threads.These same threads penetrate into the cranial cavity, using for this purpose holes in the lamina of the ethmoid bone of the nose, and then join the olfactory bulb, which passes into the olfactory tract. The bulb lies on the base of the skull and makes up a special portion of the brain.
The system of the visceral brain, or the limbic system, includes the cortical zones of the olfactory analyzer. These same systems are responsible for the regulation of innate activity - search, food, defensive, sexual, emotional. The visceral brain is also related to the maintenance of homeostasis, the regulation of vegetative functions, the formation of motivational behavior and emotions, and the organization of memory.
The organ of smell can influence the thresholds of color perception, taste, hearing, and excitability of the vestibular apparatus. It is known that if the sense of smell of a person decreases sharply, then the pace of his thinking slows down. The structure of the organ of smell is special, it distinguishes it from other senses. All structures of the olfactory analyzer take an important part in the organization of emotions, behavioral reactions, memory processes, autonomic-visceral regulation, regulation of the activity of other areas of the cerebral cortex.
There are some substances that have a pungent odor (ammonia, acetic essence). They can have both an olfactory effect and an irritant to the sensitive fibers of the trigeminal nerve. This explains the specificity of the formation of smell sensations. Respiratory rate, pulse, blood pressure under the influence of olfactory stimuli can change reflexively.
The sharpness of smell can be judged by the fact that a person is able to clearly perceive, for example, the smell of 0.0000000005 shares of a gram of rose oil or musk, approximately 4.35 shares of a gram of mercaptan gas. If the air contains even 0,00000002 g per 1 cm3hydrogen sulfide gas, it is clearly palpable by us.
There are smells that have great strength and durability and can even be stored for 6-7 thousand years. An example of this is the smell that people who participated in the excavations of the Egyptian pyramids felt. It can be said that our nose is able to detect in the inhaled air various impurities of odorous substances in very small quantities that cannot be measured even with the help of chemical research. It is proved that the sharpness of smell depends on the time of day (after sleep, smells are better felt) and the physiological state of a person.The sense of smell is more acute when a person experiences hunger, as well as during spring and summer.
The human sense of smell is able to distinguish no more than several thousand different shades of odors. In this we are very far behind animals. Dogs, for example, can recognize about 500 thousand odors.
Smell and emotions
Brain research suggests that the olfactory brain in the process of evolution gradually formed the forebrain hemispheres, which are responsible for higher nervous activity. Smell is the primary source and method of transmitting various information among creatures in nature. In addition, for all animals and for primitive humans, the olfactory organ is necessary for finding food, a sexual partner, warning about danger or marking a habitat zone.
For a person living in the modern world, the main method of transmitting information becomes verbal, which could oust all others that have arisen earlier. It is known that smell has a powerful effect on the emotional sphere, as well as the processes associated with it. This effect often occurs at the subconscious level.This experience in human life is not always positive. For example, manifestations of diseases in the form of psychosomatic diseases are recorded.
Great sense of smell
The functions of the olfactory organ are numerous in the life of all living beings, as it is able to warn about the danger of poisoning with poisonous gases that can enter the body through the lungs. It is also possible to control with the help of the smell the quality of the food consumed, which protects decomposed and poor-quality products from getting into the gastrointestinal tract.
As a conclusion, it can be said that the close connection between long-term memory, emotions and smell suggests that smell is a powerful means of influencing the entire human body and its world perception as a whole.