Humans Can Detect Buried Objects Without Touching Them, Study Finds

Recent research suggests that humans have a surprising ability—we can sometimes feel a physical object before making contact with it.

In a study published this past October in the journal IEEE International Conference on Development and Learning, researchers found that, similarly to some shorebirds, we have a form of “remote touch.” Simply put, when you move your hand through granular materials like sand, you can feel an object buried in said material before touching it directly.

“It’s the first time that remote touch has been studied in humans and it changes our conception of the perceptual world (what is called the ‘receptive field’) in living beings, including humans,” Elisabetta Versace, co-author of the study and lead of the Prepared Minds Lab at Queen Mary University of London, said in a university statement.

Better than robots

Versace and her colleagues asked 12 study participants to gently move their fingers through sand to find a hidden cube before touching it. This approach revealed that humans have remote touch comparable to that of some shorebirds, like sandpipers and plovers—even though we don’t have their specialized beak structures that allow for their sense.

This is the first time researchers have documented this tactile skill in humans. So how do we do it? The team found that human hands are sensitive enough to identify buried objects by feeling tiny displacements in the sand around them. In fact, the participants were 70.7% precise within the expected detectable range.

The researchers also tested the remote touchability of a robotic tactile sensor (because why not?). While on average, the robot could find objects from slightly farther distances, it often yielded false positives and had only 40% overall precision. Both humans and the robot achieved close to the maximum sensitivity researchers had predicted. In other words, robots can take our jobs, but we can still find things buried in the sand with slightly more precision.

Practical applications

Remote touch in humans is surprising but probably not a very useful skill on its own. However, “the discovery opens possibilities for designing tools and assistive technologies that extend human tactile perception,” explained Zhengqi Chen, a co-author of the study and PhD student of the Advanced Robotics Lab at Queen Mary University of London.

“These insights could inform the development of advanced robots capable of delicate operations, for example locating archaeological artifacts without damage, or exploring sandy or granular terrains such as Martian soil or ocean floors,” he added. “More broadly, this research paves the way for touch-based systems that make hidden or hazardous exploration safer, smarter, and more effective.”