The person has five basic senses: touch, sight, hearing, smell and taste. The interconnected sense organs send information to the brain to help us understand and. People also have other senses in addition to the main five. Here's how they work.
People have many senses. But traditionally the five human senses are recognized as sight, hearing, taste, smell and touch. There is also the ability to detect stimuli other than those regulated by these most widely recognized senses, and these sensory modalities include temperature (thermal detection), kinesthetic sense (proprioception), pain (nociception), balance, vibration (mechanoception), and various internal stimuli (e.g. , different chemoreceptors for determining the concentration of salt and carbon dioxide in the blood, hunger and thirst).
Having made these remarks, let's look at the basic five human senses:
Touch
The sense of touch is considered the first sense that humans develop, according to the Stanford Encyclopedia. The sense of touch consists of several different sensations transmitted to the brain through specialized neurons in the skin. Pressure, temperature, light touch, vibration, pain and other sensations are part of the sense of touch and are all attributed to various receptors on the skin.
Touch is not just a sense used to interact with the world; it also seems to be very important for a person's well-being. For example, touch as compassion of one person to another.
This is the sense by which we distinguish the various qualities of bodies: such as warm and cold, hardness and softness, roughness and smoothness.
Vision
Seeing or perceiving with the eyes is a complex process. First, light is reflected from the object to the eye. The transparent outer layer of the eye, called the cornea, bends light as it passes through the pupil. The pupil (which is the colored part of the eye) works like a camera shutter, shrinking to let in less light or opening wider to let in more light.
The cornea focuses most of the light, and then the light passes through the lens, which continues to focus the light.
The lens of the eye then bends the light and focuses it on the retina, which is full of nerve cells. These cells are shaped like rods and cones and are named after their shapes. The cones translate light into colors, central vision and detail. Wands also give people vision when there is limited light, such as at night. The information translated from the light is sent as electrical impulses to the brain via the optic nerve.
Hearing
Hearing works through the complex labyrinth that is the human ear. Sound is directed through the outer ear and fed into the external auditory canal. The sound waves then reach the eardrum. It is a thin sheet of connective tissue that vibrates when sound waves reach it.
Vibrations travel to the middle ear. The auditory ossicles vibrate there—three tiny bones called the malleus (hammer), incus (anvil), and stapes (stirrup).
People maintain their sense of balance because the eustachian tube, or pharyngo-matian tube, in the middle ear equalizes air pressure with atmospheric pressure. The vestibular complex in the inner ear is also important for balance because it contains receptors that regulate the sense of balance. The inner ear is connected to the vestibulocochlear nerve, which transmits sound and balance information to the brain.
Smell
The sense of smell, by which we distinguish odors, different kinds of which convey different impressions to the mind. The organs of animal and vegetable origin, as well as most other bodies, when exposed to air, constantly send out odors, as well as a state of life and growth, as in a state of fermentation and putrefaction. These effluvia, drawn into the nostrils along with the air, are the means by which all bodies exude.
Humans can smell more than 1 trillion scents, researchers say. They do this with the olfactory fissure, which is located at the top of the nasal cavity, next to the olfactory bulb and fossa. The nerve endings in the olfactory fissure transmit odors to the brain.
In fact, a poor sense of smell in humans can be a symptom of a health condition or aging. For example, a distorted or reduced ability to smell is a symptom of schizophrenia and depression. Old age can also reduce this ability. According to data published in 2006 by the National Institutes of Health, more than 75 percent of people over the age of 80 may have severe olfactory disorders.
Taste
Taste is usually categorized into the perception of four different tastes: salty, sweet, sour, and bitter. There may be many other flavors that have not yet been discovered. In addition, spicy, the taste is not.
The sense of taste helps people to check the food they eat. A bitter or sour taste indicates that the plant may be poisonous or rotten. Something salty or sweet, however, often means the food is rich in nutrients.
Taste is felt in the taste buds. Adults have between 2,000 and 4,000 taste buds. Most of them are on the tongue, but they also extend the back of the throat, epiglottis, nasal cavity, and esophagus.
It is a myth that the tongue has specific zones for each flavor. The five tastes can be felt in all parts of the tongue, although the sides are more sensitive than the middle. About half of the sensory cells in taste buds respond to several of the five basic tastes.
Cells differ in the level of sensitivity. Each one has a specific palette of tastes with a fixed ranking, so some cells may be more sensitive to sweet, followed by bitter, sour, and salty. A complete picture of taste is produced only after all information from different parts of the tongue is combined.
In this painting by Pietro Paolini, each individual represents one of the five human senses. sixth sense of man
In addition to the traditional big five, there is the sixth human sense, the sense of space, which is about how the brain understands where your body is in space. This sense is called proprioception.
Proprioception involves the sense of movement and position of our limbs and muscles. For example, proprioception allows a person to touch the tip of their nose with their finger even when their eyes are closed. This allows a person to climb the steps without looking at each one. People with poor proprioception can be clumsy.
Researchers at the National Institutes of Health (NIH) have found that people who have particularly poor proprioception, like feeling when someone is pressing on your skin (may have a mutated gene that is passed down from generation to generation) may not work, so their neurons cannot detect touch or limb movements.
People's Feelings: List
Here is a list of other human senses regarding the main five senses:
- Pressure
- Temperature
- Thirst
- Hunger
- Direction
- Time
- muscle tension
- Proprioception (the ability to recognize your body in detail, relative to other body parts)
- Sense of balance (the ability to balance and feel the movement of the body in terms of acceleration and change of direction)
- Stretch receptors (They are found in places like the lungs, bladder, stomach, blood vessels, and gastrointestinal tract.)
- Chemoreceptors (This is the medulla oblongata trigger in the brain that is involved in detecting blood. It is also involved in reflex vomiting.)
Subtle human feelings
There are more subtle human feelings that most people never perceive. For example, there are neuron sensors that sense movement to control balance and head tilt. Specific kinesthetic receptors exist to detect stretch in muscles and tendons, helping people keep track of their limbs. Other receptors detect oxygen levels in certain blood flow arteries.
Sometimes people don't even perceive feelings in the same way. For example, people with synesthesia may see sounds as colors or associate certain sights with smells.
5. Sense organs
The sense organs are the gates of perception. They connect us to the outside world. These are the windows of our soul, we look through them in order to finally see ourselves. Because the external world, which we know through the senses and in the unshakable reality of which we firmly believe, does not really exist.
Let's try gradually, step by step, to understand everything that sounds, at first glance, so terrible. So how does our perception function? Any act of sensory perception forces us to confine ourselves to the information that arises when the vibration of particles changes. For example, we look at an iron stick and see that it is black, we feel the coldness of the metal, a specific smell, we feel how hard it is to the touch. Now let's take a Bunsen burner and heat up this stick. We will see how its color changes, we will see how red flashes pass through it, we will feel the heat emanating from it, we will be able to notice its mobility. What happened? We introduced energy into the stick, which changed the speed of particles in it. The increase in speed led, in turn, to a change in perception, which can be described by the words "red", "hot", "moving", etc.
This means that our perception is based on the vibration of particles and the change in its frequency. The particles hit the specific receptors of our organs of perception, cause irritation, which, with the help of chemical-electrical impulses through the nervous system, enters the brain and creates a complex image. We call it “red”, “hot”, “fragrant”, etc. Particles enter, and complex images of perception go out. Between them is the process of processing. It seems to us that the complex images that our consciousness creates from the information received from the particles really exist outside of us. But actually it is not! Outside, only particles exist. Of course, our perception is based on particles, but we are not able to perceive them as such. Therefore, we are surrounded only by our subjective images.. Of course, it seems to us that other people (do they really exist?) perceive the same thing, because they use the same words to describe their perception as we do. But two people can never be completely sure that they are seeing the same thing, although both describe what they see with the word "green." We are alone in the circle of our own images, but we do our best to avoid this truth.
The images seem natural to us, as natural as in a dream, but only if this dream is dreamed long enough. One fine day, a person will wake up from his sleep and be surprised: the world that seemed so real has turned into nothing - into an illusion, maya, a haze that obscures reality for us. If you follow the line of reasoning carefully, you might object that although our environment does not exist in the form that we perceive, the external world is still there, it is made up of particles.
But this is also deceptive. After all, at the level of particles there are no boundaries between “I” and “not-I”, between external and internal. The particle doesn't care, it doesn't show whether it belongs to me or to the external environment. There are no boundaries at all. Everything is one here.
This is what the ancient esoteric principle means: "microcosm = macrocosm." The equal sign is used here with mathematical precision. "I" (Ego) is an illusion, an artificial boundary existing in consciousness - until a person learns to sacrifice his "I" in order to realize, to his greatest surprise, that loneliness, which he was so afraid of, is in fact unity of everything in everything. But the path to this unity - the path of the initiates - is long and difficult. The sense organs connect us with the illusory world of matter.
At the beginning of this chapter, we said that the sense organs are the windows of our soul, through which we can see ourselves. Everything that we call the inner or outer world is a reflection of our soul. The mirror makes it possible to see and get to know ourselves better, because it also shows us those aspects of ourselves that cannot be seen by ourselves. The surrounding world is a grandiose mirror of self-knowledge. Since the picture that we see there does not always please us, because our shadow is also reflected in it, it is very important for us to separate the external from ourselves and emphasize that "we have absolutely nothing to do with this."
It is very dangerous. We project what we are onto the outside world and believe in the independence of this projection. At the same time, we forget to take our projections back - and the era of social work begins, when everyone helps everyone, and no one helps himself. For the formation of consciousness, an external reflection is necessary, but we must not forget to absorb it into ourselves, if, of course, we want to regain our integrity. Let's go back to the myth of the creation of woman. From the perfect androgynous creature, Adam, was taken one side, which was given the status of formal independence. Thus, Adam began to miss his half, but he found it in the outside world - in Eve. Adam could regain his wholeness only if he united with what he lacks. This could happen only with the help of the external.
If a person does not pay due attention to what he perceives in the mirror of the outside world, if he does not gradually, step by step, fill his life path with meaning and get rid of tempting illusions, if he believes that he has nothing to do with the outside world, then fate gradually begins to interfere with his perception.
To perceive means to take into account. This can only happen if a person is aware of himself in everything. If he forgets about it, the windows of the soul will gradually become clouded and become opaque. When the sense organs begin to weaken their functions, a person must inevitably learn to look inside himself, to listen to what is happening inside, that is, to return to himself.
There is a meditation technique in which the return to oneself occurs voluntarily. With his fingers, the meditator closes all the "gates of the soul": eyes, mouth, ears - and then turns to the corresponding internal sensory perceptions, which, with a certain training, manifest themselves in the form of taste, color and sound.
11. Sense organs in children Research methods Vision. The newborn is characterized by moderate photophobia, his eyes are almost constantly closed, the pupils are constricted, the lacrimal glands do not function.
LECTURE No. 5. Sense organs 1. Sense organs in children (vision, hearing, smell, taste, skin sensitivity) Vision. Eye laying occurs on the 3rd week of intrauterine development. By birth, the development of the eye and visual analyzer is not completed.
1. Sense organs in children (vision, hearing, smell, taste, skin sensitivity) Vision. Eye laying occurs on the 3rd week of intrauterine development. By birth, the development of the eye and the visual analyzer is not completed. The newborn is characterized by moderate photophobia, his
PART 2. SENSORS
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5 human senses
How many main sense organs does a person have?
In total, it is customary for a person to share 5 senses. Depending on the origin, they are divided into three types.
- The organs of hearing and vision come from the embryonic neural plate. These are neurosensory analyzers, refer to first type.
- The organs of taste, balance and hearing develop from epithelial cells that transmit impulses to neurocytes. These are sensory-epithelial analyzers, they belong to second type.
- Third type includes peripheral parts of the analyzer that sense pressure and touch.
visual analyzer
The main structures of the eye: the eyeball and auxiliary apparatus (eyelids, muscles of the eyeball, lacrimal glands).
The eyeball has an oval shape, is attached with the help of ligaments, and can move with the help of muscles. Consists of three shells: outer, middle and inner. Outer shell (sclera)- this protein shell of an opaque structure surrounds the surface of the eye by 5/6. The sclera gradually passes into the cornea (it is transparent), which is 1/6 of the outer shell. The transition area is called the limbus.
Middle shell consists of three parts: choroid, ciliary body and iris. The iris has a colored color, in the center of it is the pupil, due to its expansion and contraction, the flow of light to the retina is regulated. In bright light, the pupil constricts, and in low light, on the contrary, it expands to catch more light rays.
Inner shell is the retina. The retina is located at the bottom of the eyeball, provides light perception and color perception. The photosensory cells of the retina are rods (about 130 million) and cones (6-7 million). Rod cells provide twilight vision (black and white), cones serve for daytime vision, color discrimination. The eyeball has inside the lens and chambers of the eye (anterior and posterior).
The value of the visual analyzer
With the help of the eyes, a person receives about 80% of information about the environment, distinguishes colors, shapes of objects, and is able to see even with minimal light. The accommodative apparatus makes it possible to maintain the clarity of objects when looking into the distance, or close reading. Auxiliary structures protect the eye from damage, pollution.
auditory analyzer
The organ of hearing includes the outer, middle and inner ear, which perceive sound stimuli, generate an impulse and transmit it to the cortex of the temporal zone. The auditory analyzer is inseparable from the organ of balance, therefore the inner ear is sensitive to changes in gravity, to vibration, rotation, and movement of the body.
outer ear It is divided into auricle, ear canal and tympanic membrane. The auricle is an elastic cartilage, with a thin ball of skin, that determines the sources of sound. The structure of the external auditory canal includes two parts: cartilaginous at the beginning and bone. Inside are glands that produce sulfur (has a bactericidal effect). The eardrum receives sound vibrations and transmits them to the structures of the middle ear.
Middle ear includes the tympanic cavity, inside which are the hammer, stirrup, anvil and Eustachian tube (connects the middle ear with the nasal part of the pharynx, regulates pressure).
inner ear divides into a bony and membranous labyrinth, with perilymph flowing between them. The bony labyrinth has:
- vestibule;
- three semicircular canals (located in three planes, provide balance, control the movement of the body in space);
- cochlea (it contains hair cells that perceive sound vibrations and transmit impulses to the auditory nerve).
The value of the auditory analyzer
Helps to navigate in space, distinguishing between noises, rustles, sounds at different distances. With its help, information is exchanged when communicating with other people. From birth, a person hearing oral speech, he learns to speak. If there are congenital hearing impairments, then the child will not be able to talk.
The structure of the human sense of smell Receptor cells are found in the back of the upper nasal passages. Perceiving odors, they transmit information to the olfactory nerve, which delivers it to the olfactory bulbs of the brain.
With the help of smell, a person determines the good quality of food, or smells a threat to life (carbon smoke, toxic substances), pleasant aromas cheer up, the smell of food stimulates the production of gastric juice, promoting digestion.
organs of taste
On the surface of the tongue there are papillae - these are taste buds, on the apical part of which there are microvilli that perceive taste.
The sensitivity of receptor cells to food products is different: the tip of the tongue is susceptible to sweet, the root to bitter, the central part to salty. Through the nerve fibers, the generated impulse is transmitted to the overlying cortical structures of the taste analyzer.
sense organs
A person can perceive the world around him through touch, with the help of receptors on the body, mucous membranes, and in the muscles. They are able to distinguish between temperature (thermoreceptors), pressure levels (baroreceptors), and pain.
Nerve endings have high sensitivity in the mucous membranes, earlobe, and, for example, the susceptibility of receptors in the back is low. Touch makes it possible to avoid danger - remove your hand from a hot or sharp object, determines the degree of pain threshold, signals an increase in temperature.
Appeared, thanks to the meditation of seers, true rishis. For thousands of years their teachings were transmitted orally from teacher to student, and later these teachings became the subject of melodic Sanskrit poetry. Although many of these texts have been lost over time, much of the Ayurvedic knowledge has survived.
This wisdom, originating in the Cosmic Consciousness, was received by the hearts of the Rishis. They realized that consciousness is energy manifested in five basic principles or elements: ether (space), air, fire, water and earth. Ayurveda is based on this concept of five elements.
The Rishis realized that in the beginning the world existed in the form of unmanifested consciousness. Out of this universal consciousness emerged the soundless sound of "AUM" as a subtle cosmic vibration. From this vibration, the element of ether first arose.
Then this element of ether began to move, and this subtle movement created air, which is the mobile ether. The movement of the aether contributed to the emergence of friction, which generated heat. Particles of heat energy combined into a form of intense luminosity, and from this light, the element of fire manifested.
So the ether was transformed into air, and it was the same ether that later manifested itself in the form of fire. Generally, heat dissolves and liquefies the ethereal elements, revealing the water element, and then solidifies to form earth molecules. Thus, the ether is manifested in four elements: air, fire, water and earth.
All original living bodies were created from the earth, including the vegetable and animal kingdoms, as well as man. The earth is also contained in inorganic substances, which include the mineral kingdom. Thus, all matter is born from the womb of the five elements.
In all matter, these 5 elements exist. Water is a classic example that proves this: the solid state of water - ice - is a manifestation of the earth principle. The latent heat (fire) in the ice melts it, revealing water, and then there is a transformation into steam, indicating the air principle.
The vapor disappears into ether or space. Thus, in one substance there are 5 basic elements: ether, air, fire, water and earth.
All 5 elements arise from the energy emanating from the Cosmic Consciousness, all 5 are present in matter everywhere in the Universe. Thus, energy and matter represent a single principle.
Man as a microcosm
Man is a microcosm. Just as the 5 elements are everywhere in matter, they also exist in every person. There are many places in the human body where the element of ether is manifested. For example, there is space in the mouth, nose, gastrointestinal tract, respiratory tract, abdomen, chest, capillaries, lymph, tissues and cells.
The space in motion is called air.
Air is the second cosmic element, the element of motion. In the human body, air manifests itself in the diverse movements of the muscles, the pulsation of the heart, the expansion and contraction of the lungs, and in the movements of the walls of the stomach and intestinal tract.
Under the microscope, you can see that even the cell is in motion. The reaction to irritation is the movement of nerve impulses, manifested in sensory and motor movements. All movements of the central nervous system are entirely controlled by air.
The third element is fire. The source of fire and light in the solar system is the sun. In the human body, the source of fire is metabolism, metabolism. Fire works in the digestive system. Fire manifests itself as intelligence in the gray matter of brain cells.
Fire also manifests itself in the retina of the eye, which perceives light. Thus, body temperature, digestion, thinking and the ability to see are all functions of fire. The entire metabolism and enzyme system is controlled by this element.
Water is the fourth important element in the body. It manifests itself in the secretion of gastric juice and salivary glands, in mucous membranes, in plasma and protoplasm. Water is vital for the functioning of tissues, organs and various body systems.
For example, dehydration resulting from vomiting and diarrhea must be treated immediately to save the patient's life. Because water is so vital, the water in the body is called the Water of Life.
Earth is the fifth and last element of the cosmos that is present in the microcosm. Life becomes possible at this level because the earth holds everything living and non-living on its surface.
The solid structures of the body—bones, cartilage, legs, muscles, tendons, skin, and hair—all came from the earth.
Feelings (perceptions)
These 5 elements are manifested in the functions of the five senses of a person, as well as in his physiology. These elements are directly related to a person's ability to perceive the world around him. Through the sense organs, they are also associated with the five actions corresponding to the functions of the sensory organs.
The basic elements, ether, air, fire, water, and earth, are associated with hearing, touch, sight, taste, and smell, respectively.
Ether is the medium that transmits sound. This ethereal element is associated with the function of hearing. The ear, the organ of hearing, expresses action through the organs of speech, which give meaning to human sound.
Air is associated with the sense of touch; the organ of touch is the skin. The organ that transmits the sense of touch is the hand. The skin on the hand is very sensitive, the hand is endowed with the ability to hold, give and receive.
Fire, manifested as light, heat and color, is associated with vision. The eye, the organ of vision, governs walking and is thus associated with the foot. A blind person can walk, but without choosing a direction. The eyes give direction to actions when walking.
Water is associated with the organ of taste; without water, the tongue cannot taste. The tongue is closely related to the functions of the genitals (penis and clitoris). In Ayurveda, the penis or clitoris is considered the lower tongue, and the tongue in the mouth is the higher tongue. The person who controls the higher language naturally controls the lower language.
The earth element is associated with the sense of smell. The nose, the organ of smell, is functionally related to the actions of the anus, the organ of excretion. This connection is manifested in a person who has constipation or an unclean rectum - he has bad breath, his sense of smell is dulled.
Ayurveda refers to the human body and its sensory sensations as a manifestation of cosmic energy, expressed in five basic elements. The ancient rishis realized that these elements originate from pure Cosmic Consciousness.
Ayurveda seeks to enable each individual to bring his body into a perfect and harmonious connection with this Consciousness.
5 elements, sense organs and their actions
| element | the senses | sense organs | action | organ of action |
| Ether | Hearing | Ear | Speech | Organs of speech (tongue, vocal cords, mouth) |
| Air | Touch | Leather | holding | Hand |
| Fire | Vision | Eyes | Walking | Leg |
| Water | Taste | Language | Playback | Genitals |
| Earth | Smell | Nose | Selection | anus |
Humans have five basic senses: touch, sight, hearing, smell and taste. The sense organs associated with each sense send information to the brain to help us understand the world around us. In addition to the main five people, there are also other senses. Here's how they work.
Touch
The sense of touch is considered the first sense that a person develops. It consists of several different sensations transmitted to the brain through specialized neurons in the skin. Pressure, temperature, light touch, vibration, pain and other sensations are part of the sensory experience and are all attributed to various receptors on the skin.
Touch is not just a sense used to interact with the world; it also seems to be very important for human well-being.
The sense of touch can also influence how people make decisions. Texture can be associated with abstract concepts, and touching something can influence a person's decisions, according to six studies by psychologists from Harvard University and Yale University, published in the journal Science on June 24, 2010.
These tactile sensations do not just change the general orientation, but create a mood. They have a certain connection with some abstract meanings."
Vision
Seeing or perceiving things with the eyes is a complex process. First, light is reflected from the object to the eye. The transparent outer layer of the eye, called the cornea, bends light as it passes through the pupil. The iris (which is the colored part of the eye) works like a camera shutter, retracting to turn off the light or opening wider to let in more light.
The cornea focuses most of the light, and then the light passes through the lens, which continues to focus the light.
The lens of the eye then bends the light and focuses it on the retina, which is full of nerve cells. These cells are shaped like rods and cones and are named after their shapes. Cones translate light into colors, central vision, and details. The rods translate light into peripheral vision and movement. The sticks also give people vision when there is limited light, such as at night. The information translated from the light is sent as electrical impulses to the brain via the optic nerve.
Even in the case of profound blindness, the brain works in such a way as to use the information at its disposal so that it can interact more effectively with the environment.
Hearing
This feeling works through the complex labyrinth that is the human ear. Sound is directed through the outer ear and fed into the external auditory canal. The sound waves then reach the eardrum. It is a thin sheet of connective tissue that vibrates when sound waves hit it.
Vibrations travel to the middle ear. The auditory ossicles vibrate there—three tiny bones called the malleus, anvil, and stirrup. The latter, in turn, pushes a structure called the oval window and sends vibrations to the organ of Corti. This spiral organ is the receptor organ for hearing. The tiny hair cells in it translate vibrations into electrical impulses. The impulses then travel to the brain via sensory nerves.
People maintain their sense of balance because the Eustachian tube, in the middle ear, equalizes the air pressure in the middle ear with the air pressure in the atmosphere. The vestibular complex in the inner ear is also important for balance because it contains receptors that regulate the sense of balance. The inner ear is connected to the vestibulocochlear nerve, which transmits sound and balance information to the brain.
Smell
Humans can smell more than 1 trillion scents, researchers say. They do this with the olfactory cleft, which is located on the roof of the nasal cavity, next to the "olfactory" part of the brain, the olfactory bulb and fossa. Nerve endings in the olfactory fissure transmit odors to the brain.
Dogs are known for their good sense of smell, but studies show that humans are just as good at it as man's best friend. A study published in Science on May 11, 2017 suggests that humans can distinguish 1 trillion different odors; It was once thought that humans could only perceive 10,000 different odors.
Humans have 400 olfactory receptors. It's not as many as some animals, but the much more complex human brain makes up for the difference.
In fact, a poor sense of smell in humans may be a symptom of illness or aging. For example, a distorted or reduced ability to smell is a symptom of schizophrenia and depression. Old age can also reduce the ability to smell. More than 75% of people over the age of 80 may have severe olfactory disorders.
Taste
This sense is usually subdivided into the perception of four different tastes: salty, sweet, sour, and bitter. There is also a fifth taste, defined as umami. There may be many other flavors that have not yet been discovered. In addition, the spicy taste is not.
The sense of taste helped in human evolution because it helped people test the food they ate. A bitter or sour taste indicated that the plant might be poisonous or rotten. Something salty or sweet, however, often means the food is rich in nutrients.
Taste is sensed by taste buds. Adults have between 2,000 and 4,000 taste buds. Most of them are on the tongue, but they also affect the back of the throat, the epiglottis, the nasal cavity, and the esophagus. The sensory cells on the kidneys form capsules in the shape of flower buds or oranges. The tips of these capsules have pores that work like funnels with tiny taste hairs. The proteins on them are bound to cells for tasting.
It is a myth that the tongue has special zones for each taste. The five tastes can be felt in all parts of the tongue, although the sides are more sensitive than the middle. About half of the sensory cells in taste buds respond to several of the five basic tastes. Cells differ in their level of sensitivity. Each has a specific palette of tastes with a fixed ranking, so some cells may be more sensitive to sweet followed by bitter, sour and salty, while others have their own ranking. The full experience of taste is produced only after all the information from different parts of the tongue has been combined.
The other half of the sensory cells are specialized to respond to only one taste. Their task is to convey information about the intensity - like a salty or sweet taste.
Other factors help shape the perception of taste in the brain. For example, the smell of food greatly affects how the brain perceives taste. Smells are sent to the mouth in a process called olfactory referral. This is why a stuffy nose can have trouble tasting food properly. Texture translated by the sense of touch also contributes to taste.
Sense of space
In addition to the traditional big five, there is also a sense of how your brain understands where your body is. This is called proprioception.
Proprioception involves the sense of movement and position of our limbs and muscles. For example, proprioception allows a person to touch the tip of their nose with their finger even when their eyes are closed. This allows a person to climb the steps without looking at each one. People with poor proprioception can be clumsy and incoherent.
People who have particularly poor mechanosensation proprioception—the ability to sense force, such as the feeling when someone is pressing on your skin—may have a mutated gene that is passed down from generation to generation.
Additional Feelings and Variations
There are more subtle feelings that most people never perceive. For example, there are neuron sensors that sense movement to control balance and head tilt. Specific kinesthetic receptors exist to detect stretch in muscles and tendons, helping people keep track of their limbs. Other receptors detect oxygen levels in certain blood flow arteries.
Sometimes people don't even perceive feelings in the same way. For example, people with can see sounds as colors or associate certain sights with smells.
