Mad Science with Mads: the science behind a papercut

Madeline Bombardi

It is hard to imagine that something as harmless as a to-do list could cause such significant pain when swept across a finger.

Some may know it all too well, the horrid paper cut. A cut that is considered a minor injury may result in an immediate throbbing pain. How is it possible that something that is seemingly insignificant can hurt so much?

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Paper Cut Weds. 2
(Photo Illustration: Maria Nateras.)

To begin, let’s examine the human hand. The human hand has a large amount of nerve endings that lay just underneath the epidermis, or the skin. Nerve endings send electric signals to other nerves. For example, when one touches a piece of a ice, these nerve endings send signals to other nerves that then tell the brain what the hand is experiencing.

A sensory receptor is the area where the stimuli are received. These receptors respond to the stimuli and transmit chemicals from one nerve to another nerve. Therefore, these chemicals affect how nerves “talk” to each other. Nerve endings and sensory receptors send a wealth of information to the brain. The nerves in human hands inform the brain of the dangers that may exist in an environment.

According to “The Human Brain Book,” edited by Rita Carter, the human hand has approximately four major types of receptors: pain receptors, pressure/texture receptors, temperature receptors and proprioceptors (receptors that coordinate where the body is in space). These receptors are highly sensitive to many forms of sensation, making our fingers especially susceptible to discomfort, aching or soreness.

When a finger is cut, the receptors in that area are exposed, and the pain receptors continually fire signals to the brain. The pain subsides when the body produces enough cells to rebuild the affected skin.

One of the main reasons paper cuts hurt more is due to the fact that paper has a serrated edge. Paper appears as though it would slice the skin with one clean sweep. However, when examined under a microscope, paper has a rather jagged edge, which cuts the skin unevenly. A laceration from a serrated edge requires an extended healing time, compared to one caused by an even blade, such as a knife.

Another reason these types of cuts hurt is due to the fact that paper is often made with chemicals. When the paper cuts the finger, the chemicals enter the wound and irritate it. Paper cuts are surface-level injuries and do not bleed much. If the cut were to bleed, then it would clot and close the wound. Since paper cuts do not bleed all that much, the wound stays open and exposed.

Remedies for paper cuts vary from person to person.

CSU alumna Robyn Cowley said she just sucks on a paper to make it feel better.

Justin Patry, a CSU graduate student majoring in journalism and media communication, said he washes the cut and applies a topical antibiotic as his paper cut remedy.

“You have to properly take care of wounds or they can get infected,” Patry said. “I actually carry a small medical kit in my bag at all times.”

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The best advice may be to avoid paper all together — it is the digital age, after all.

Collegian Science Beat Reporter Madeline Bombardi can be reached at news@collegian.com or on Twitter @madelinebombard.