The Five Senses of The Human Body: Facts Figure & Functionality
- Last Updated: Dec 27th, 2018
- Posted by: admin
- Category: Health & Wellness
Just think about what happens when your Mom or Dad calls you for dinner? At that time, you can hear them asking you to wash your hands before coming to eat, you feel the water and soap against your skin, you can smell what’s cooking, and finally taste the food on your plate. This is all because of your working five senses.
Living creature is an amazing miracle of God’s creation. From the very beginning, God created the earth. Subsequently, he created the “LIFE” or “HUMAN“ which became the most powerful creatures on the earth due to his wondrous power of SENSATION.
Normally, a sense is a physiological capacity or conscious awareness of organisms that supply information for perception. Apparently, the senses allow us to experience the world around us. It might be unimaginable to live our lives without our five sense organs.
What are the five senses organs of a human body
The nervous system of our body receive and process the information and later, relay the signals to the brain in order to react with the world. Much of this information reaches us through the 5 senses organs. Those are the eyes, ears, nose, tongue, and skin. However, Sight (vision) must be the most delightful of all the senses. But touch (skin) comes before sight, or even before speech. It is the first expression and the last, and it always mentions the truth.
There are different receptors in each sense organs. One is general receptors and other is special receptors.
- Skin contains general receptors
- Mouth and nose contain a special receptors that is called chemo-receptors (chemical receptors)
- Eyes also contain a special receptors known as photo-receptors (light receptors)
- Ears contain mechanoreceptors which are also a special receptor.
To illustrate the above, human bodies have five recognized senses: sight, hearing, taste, smell, and touch. Here is a brief description of each of these.
5 senses of the body and their functions
Our sense organs consist of – eye, ears, nose, tongue and skin. And they provide the sense of sight, hearing, smell, taste and touch respectively. Lets discuss these five senses in detail.
The sense of SIGHT (Ophthalmoception)
The process of perceiving the objects through the eyes is called as sight. Lets discuss the mechanism of sight.
An eye is an organ responsible for the vision to detects visible images and most use more than any other sense. The light reflects off an object to the eye. The transparent outer layer of the eye called the cornea bends the light that passes through the hole of the pupil. The iris (which is the colored part of the eye) works like the shutter of a camera, retracting to shut out light or opening wider to let in more light. An eye translates light into image signals for the brain through the various parts like sclera, the cornea, anterior & posterior chambers, iris, pupil, lens, vitreous humor, retina, fovea, macula, and the ophthalmoscope.
The iris is the colored part of the eye which actually is a pigmented muscle that controls the size of the pupil. Pupil dilates to allow more light into the eye or contracts to allow less light into the eye. Cornea covered both iris and pupil. The cones and the rods are the two types of light-sensitive cells in the retina. When the cones distinguish colors, the rods allow us to see better in dim light. And, by the optic nerve, all of this information is sent to the brain.
The images actually sent are upside down but our brain help to understand what it is by turning the image on the right side up.
Problem with ophthalmoception
The inability to see is blindness, results from any damage to any part of the eyes. It may be partial or whole. Cleaning of the eyes, eye drops, surgery, and laser treatments available to cure severe vision impairment.
The sense of HEARING (Audioception)
The sense of sound perception is hearing. Our ears help us to hear. It is divided into 3 parts i.e. the outer ear, middle ear, and the inner ear. The ear uses bones, hairs, and fluid to convert sound waves into sound signals. The hearing is the mechanical motion of the vibrations detected in the inner ear through a series of tiny bones to tiny hairs.
Lets have a look on the mechanism of hearing
At first sound wave hits the eardrum, then the eardrum make the tiny bones like the malleus, incus, and the stapes moves. Mechanoreceptors picked this movement in the inner ear. These receptors exist on hair cells and it contains cilia between the vestibule and the end of the semicircular canals. As cilia move, an impulse is created by the cells that are sent to the eight cranial nerve through the cochlea. The cranial nerve carries impulse to the nerve and then the brain interprets the information as a valid sound.
Problem with Audioception
Hearing impairment or deafness is the inability of hearing. Few medications, therapies, and surgeries are recommended to cure hearing. While, in some cases, hearing aid also helpful for severe deafness to some extent.
Some impaired people are able to determine the direction and location of vibrations picked up through the feet.
The sense of TASTE (Gustation)
Taste is sensed in the taste buds. Adults have 2,000 to 4,000 taste buds.
Taste refers to the thought of flavor felt in the mouth and throat in touch with any substances such as food, certain minerals, chemicals, and toxin, etc. Remember it is fully different from the sense of smell. Taste buds, sensory organs on the top of the tongue or mouth connected to nerves in the brain. Taste buds contain chemo-receptors. The taste buds actually lie down in the grooves between each papilla. Papilla is the little bumps on the tongues.
When food touches the taste buds, it activates nervous receptors which later send signals to facial, glossopharyngeal, and vagus nerves. Those nerves carry the signals to the medulla oblongata, which deliver them to the cerebral cortex of the brain. There are five basic tastes: saltiness, sourness, sweetness, bitterness, and umami. In addition, a taste sense depends on other senses and factors, including smell, texture, and temperature.
There is also a fifth taste, defined as umami or savory. There may be many other flavors that have not yet been discovered. Also, spicy is not a taste. It is actually a pain signal, according to the National Library of Medicine (NLM).
Problem with Gustation
The incapability to taste is called ageusia. Certain medications may help to treat ageusia e.g. Topical anti-fungal or antibiotics: candidiasis/oral infections.
The sense of SMELL (Olfaction)
Humans may be able to smell over 1 trillion scents, according to researchers. Research published in the May 11, 2017, issue of the journal Science suggests that humans can discriminate among 1 trillion different odors; it was once believed that humans could take in only 10,000 different smells.
Our nose, containing the nostrils used for breathing and smelling. Without it, we couldn’t able to enjoy our favorite smells like a fragrance of cooking, a bouquet of flowers, and perfumes etc. Olfaction, a sense of smell, have minimum 390 olfactory receptors at the top of the nasal cavity. The olfactory cells are chemo-receptors, these protein receptors can detect subtle differences in chemicals. You can smell with the olfactory cleft, which is found on the roof of the nasal cavity, next to the “smelling” part of the brain, the olfactory bulb and fossa.
When inhaled, those triggers a signal that travels to the olfactory bulbs through the epithelium. The olfactory bulbs contain neuron cell bodies, they send the signal along the cranial nerves towards the cerebral cortex in the brain. Our sense of smell is able to determine seven types of sensations. Those are camphor, ether, musk, flower, mint, acrid, or putrid.
Problem with Olfaction
Anosmia is the loss of the sense of smell. Intracranial theosophy spray and smell therapies help in improving the sense of smell. Poor smelling ability may be a symptom of schizophrenia and depression. It can be due to medical condition or aging.
The sense of TOUCH (Somatosensation)
Touch is thought to be the first sense that humans develop, according to the Stanford Encyclopedia of Philosophy
Although the skin is the largest organ in our body, touch is perhaps the most unnoticed sense of the body. Nerve endings and specialized neural receptors in the skin (including hair follicles, tongue, throat, and mucous) send touch signals to the brain. Blind people can use their sense of touch to read Braille which is a type of reading or writing. Generally, touch sensation first develops in the 8 weeks of the gestation period.
The skin consists of three major tissue layers: the outer epidermis, middle dermis, and inner hypo dermis. Specialized receptor cells within these layers detect tactile sensations and send those signals through peripheral nerves towards the brain. Receptors, for example, Merkel cells, are forms in the lower epidermis of lips, hands, and external genitalia. Similarly, Meissner corpuscles are found in the upper dermis of hairless skin such as fingertips, nipples, the soles of the feet. All of these receptors detect touch, pressure, and vibration.
Problem with Somatosensation
Tactile anesthesia is the loss of the ability to feel anything touched. Paresthesia is a sensation of tingling, pricking, or numbness of the skin that occurs due to nerve damage.
Other senses of the body
Apart from these, other senses like balance and acceleration, thermoception, proprioception, pain, sexual stimulation, and other internal senses are normally stimulated within the body that leads to enhancing the human’s life.
6 Sense of body – Sense of space
Proprioception can be termed as sixth sense of the human body. It deals with how your brain understands where your body is in space. It includes the sense of movement and position of our limbs and muscles. For Example, a person can climb steps without looking at each one.
Balance and acceleration
It is the sense that allows an organism to sense body movement, direction, and acceleration, and to attain and maintain postural equilibrium and balance.
It is the sense of heat and the absence of heat (cold) by the skin and internal skin passages. It provides the parietal cortex of the brain with information on the movement and relative positions of the parts of the body. Neurologists test this sense by telling patients to close their eyes and touch their own nose with the tip of a finger.
Pain or Nociception
Physiological pain indicates nerve damage or damage to tissue. The three types of pain receptors are cutaneous (skin), somatic (joints and bones), and visceral (body organs). The main function of pain is to attract our attention to dangers and motivate us to avoid them. For example, humans avoid touching a sharp needle, or hot object, or extending an arm beyond a safe limit because it is dangerous, and thus hurts. Without pain, people could do many dangerous things without being aware of the dangers.
It is the stimulation that leads to, enhances and maintains sexual arousal, and may lead to orgasm. Distinct from the general sense of touch, sexual stimulation is strongly tied to hormonal activity and chemical triggers in the body. Although sexual arousal may arise without physical stimulation, achieving orgasm usually requires physical sexual stimulation.
All of the nerves in our body connect to the spinal cord (over our backbone), which attach to the brain. Hence, this very complex system is what allows us to sense things and thus makes our life wonderful.
We have 5 senses in our body. The 5 Senses interpret the world around us as we can find out and grasp whatever is happening around us. Watch this video to know more:
A human body is so amazing that uses different sense organs to gather surrounding information. Our 5 Senses help us to observe and understand the world better. Not everyone is able to use all five of their senses. If someone cannot use any of these senses, they may be blind, deaf, or have any other disability. You know what you can use all five of your senses simultaneously without even realizing it!