Touch is a sense that allows us to get to know the world around us. It has been assumed that there are five senses - sight, hearing, touch, taste and smell. If we looked at it more closely, we would conclude that there is more. Because touch is really a few different senses … How do the sensory nerves that make us sensitive to touch work?
The sense of touchallows us to find ourselves in our surroundings. We feel a lighttouch , strong pressure, pain, heat and cold, vibrations, and through the deep feeling we perceive the movements of our own body. Thanks to the latter, we know, for example, whether a muscle is relaxed or tense. Without looking, we also know the position of the arms, legs and the whole body. With our eyes closed, we can touch the nose one by one with the tips of all fingers.Feelingdeep is closely related to the sense of balance, which is neglected when exchanging senses. And it is he who allows us to stand upright and not fall over. Specifically, maintaining balance is a combination of what the middle ear's equilibrium organs tell us, what the eyes see, the skin (superficial sensation) and the muscles (deep sensation) register.
Touch - what and how do we feel?
Nerve margins are specialized - some are sensitive to light touch, others to pain or vibration, others to heat and cold. Irritation of the end body produces an electrical impulse in the connected sensory nerve. The impulse goes through peripheral sensory nerves to the spinal cord and then to the cerebral cortex. There, tactile stimuli and stimuli coming from other senses are compared. In this way, we recognize objects or, for example, realize the danger (pain + heat=burn).
- Sensitive fingertips
Our skin is not equally sensitive everywhere. The fingertips are the most sensitive - there are more nerve endings there than anywhere else on the skin. Therefore, it is enough to touch something very gently to find out the shape, texture and hardness. There are many sensory endings in the tongue, lips, tip of the nose, lower face, and toes. Least - in the skin of arms, thighs and back.
ImportantThanks to an extensive sense of touch, we can partially eliminate the deficiencies of other senses, e.g. the blind read Braille with their fingertips, and Beethoven, after losing his hearing, was able to "listen" to music, feeling the vibrations of his headapplied to the piano.
We feel the tactile sensations thanks to the so-called end bodies of the sensory nerves, located deeper or shallower in the skin. There are bulbous, lamellar, tactile, sexual nerve bodies and tactile meniscuses. They perceive sensations such as touch, pain (and the like: stinging, burning, itching), heat and cold.
Deep inside the body are the organs of deep feeling. And so, for example, in articular bags, we find articular nerve bodies. Muscle innervation (the tissue surrounding the bundles of muscles), ligaments, fascia and periosteum also have rich sensory innervation. Thanks to this - apart from muscle or joint pain - we can assess, for example, the hardness of the captured object, its weight, resistance, flexibility, etc.
Sensory receptors have the ability to adapt, ie "get used to" the action of a stimulus. The receptors that adapt quickly include, for example, those that are sensitive to touch and pressure. Long exposure to the stimulus causes that it is felt less and less. Some thermoreceptors are slowly adapting receptors. Interestingly, pain receptors do not adapt. They cannot - because the purpose of pain stimuli is to inform e.g. about a disease.
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