You can feel when your body is wet. It’s a very distinct sensation. Maybe you just got finished doing an ALS Ice Bucket Challenge and you’re wet right now. I’m not judging, I’m just saying you know.
But that’s a pretty neat trick, researchers at Loughborough University and Oxylane Research say, because your skin has no receptors to directly sense wetness at all. They propose that our perceptions of wetness are “perceptual illusions” our brains associate with stimuli we have experienced when wet.
The researchers theorized that when we sense wetness, what we’re really sensing is a combination of elements we do have receptors for, such as temperature, pressure and texture. They also projected that because hairy skin (like your forearm) is more sensitive to temperature than hairless skin (such as the palm of your hand) the sensation of wetness would be stronger there.
And then they tested this theory on college students. What they found was that the students were more likely to perceive cold sensations as wet than warm ones. They also found that when they dampened the students’ nerve responses to tactile stimulation by cutting them off with a blood pressure cuff they were less sensitive to wetness and their hairy skin was more sensitive than hairless skin.
“Our results provide evidence for the existence of a specific information processing model that underpins the neural representation of a typical wet stimulus,” the team wrote.
So feeling “wet” is actually a complex judgment call made by your brain as it processes more than one stimulus. You’re probably not going to be able to convince yourself you’re dry when you’re not by force of will, though, so keep your umbrella handy just in case.
[Source: American Physiological Society]
Image via Wikimedia Commons