by You’re immersed in a mystery novel, but in the excitement of discovering “whodunit” you turn the page so fast and cut the skin of your index finger. A wave of pain shoots out from the paper cut and you gasp, not because you just found out the servant did it, but because a tiny cut hurts so much.
Why is a paper cut so painful?
It’s a combination of our hands being incredibly sensitive to pain and the surprisingly rough edges of the papers.
Human hands and fingers in high concentration border cells called nociceptors that respond to signals released by damaged cells BrainFacts.org (opens in new tab). Paper cuts activate “mechanical nociceptors” that sense cell damage from pressure, cuts and punctures, as opposed to damage caused, for example, by extreme temperatures. To a lesser extent, paper cut can also activate nociceptors that are sensitive to chemical irritants such as bleaches used to lighten paper; These nerve cells can cause an itchy sensation around a paper cut.
Activated nociceptors release a series of electrical signals that travel through bundles of nerve fibers to the spinal cord; Nerve cells in the spinal cord then transmit these signals to the brain. brain. Eventually, according to medical sources, the signals reach an area of the wrinkled cerebral cortex, which is responsible for sensations of touch, temperature, and pain, known as the somatosensory cortex. StatPearls (opens in new tab).
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The somatosensory cortex curves like a headband over the surface of the brain, and different regions of the headband represent different body parts. The hands and fingers are so filled with cells sensitive to touch and pain that the dedicated areas of the headband are very large compared to before. less sensitive body parts, such as the trunk. The mouth and tongue cover a similarly large area of the headband, which helps explain why it’s so painful to cut your tongue when licking an envelope.
But anatomy isn’t the only thing that makes paper cuts oddly painful; paper itself contributes to suffering. While it may appear smooth to the naked eye, on a microscopic level, the dried, compressed wood fibers inside the paper make the edges of materials very rough. Universe (opens in new tab). This rough texture causes more extensive cellular damage than a straight, clean edge.
However, the serrated edge of the paper typically cuts only the top two layers of skin (epidermis and dermis) and therefore causes little or no bleeding. This makes the incision less likely to close with clotted blood. As a result, the aggravated nerve fibers are exposed to the elements for a long time and give pain signals when touched.
Clean the wound with soap and water to treat the paper cut; apply antibiotic ointment to prevent infection; and cover with a bandage to provide cushion and curb rashes. Ohio State University Wexner Medical Center (opens in new tab). Most paper cuts heal within two to three days, but if the cut does not heal within this time, it is best to see a doctor and have them checked for signs of infection.
