Why Do Your Fingers Always Wrinkle the Same Way in Water?New Study Offers Surprising Insights

A long day at the swimming pool or beach often leaves you with a satisfied belly, sunburn-free skin, and, of course, wrinkled fingers.

But have you ever wondered why those wrinkles form in such a consistent pattern, no matter how many times you submerge your hands in water?

A recent study published in the May 2025 issue of The Journal of the Mechanical Behavior of Biomedical Materials sheds new light on this intriguing phenomenon.

According to the study, the wrinkling patterns on our fingers, which appear after prolonged exposure to water, are not random but remarkably consistent.

This research, led by Binghamton University biomedical engineer Guy German and graduate Rachel Laytin, found that the patterns formed on the skin of our palms and soles, called glabrous skin, remain the same even after multiple immersions.

Glabrous skin, which lacks hair follicles, is packed with sensory receptors that send electrical signals to the brain, allowing us to sense our surroundings.

It’s this type of skin that wrinkles when submerged in water for long periods.

The study revealed that the wrinkling is caused by the contraction of blood vessels beneath the skin’s surface.

The team at Binghamton University tested this by immersing subjects’ fingers in water for 30 minutes, photographing their wrinkled fingers, and repeating the process at least 24 hours later.

When they compared the images, they discovered that the patterns of raised ridges and loops on the skin were identical.

German explains, “Blood vessels don’t change their position much—they move around a bit, but in relation to other blood vessels, they’re pretty static. That means the wrinkles should form in the same manner, and we proved that they do.”

In an unexpected twist, the study also made an intriguing discovery about the role of nerve damage in the wrinkling process.

German noted that participants with median nerve damage in their fingers showed no wrinkles at all.

“We’ve heard that wrinkles don’t form in people who have median nerve damage in their fingers,” German said. Median nerve damage affects the nerve that helps control feeling and movement in the hand. It can cause numbness, tingling, weakness, or pain, especially in the thumb and fingers.

A common cause is carpal tunnel syndrome.

"One of my students told us, ‘I’ve got median nerve damage in my fingers.’ So we tested him—no wrinkles!”

The findings could have important real-world applications, particularly in the field of forensics.

The ability to recognize consistent wrinkle patterns could assist in identifying bodies that have been submerged in water for extended periods. German, whose father is a retired UK police officer, recognizes the potential of this discovery in solving cases related to prolonged exposure to water.

"Biometrics and fingerprints are built into my brain," German shared.

"I always think about this sort of stuff, because it’s fascinating. I feel like a kid in a candy store, because there’s so much science here that I don’t know."