Humans have a range of senses—sight, hearing, smell, taste, and touch—although scientists continue to discover that beyond these commonly accepted sensory capabilities, we may have many others.
The latest addition has been revealed in a new study that points to evidence of what scientists call a seventh “remote touch” sense that humans possess, which involves sensing objects without even touching them. The findings, made by researchers from Queen Mary University and University College London, reveal a unique human ability once thought to be relegated to members of the animal kingdom.
Short birds, such as sandpipers and plovers, have an internal form of “remote touch” that protects them from prey that could be hiding in unseen places, like sand in their natural habitat. This enables the creatures to detect objects beneath granular materials, where mechanical cues are received from the medium.
Elisabetta Versace, Senior Lecturer in Psychology and lead of the Prepared Minds Lab at Queen Mary University of London who developed the experiments to test for this sense in humans, said what she and her colleagues found marks “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.”
The researchers focused on two studies: one involving humans and one involving robots. The human study tested fingertip sensitivity to tactile cues from buried objects. The second experiment was a robotic one that utilized a tactile-equipped robotic arm and a Long Short-Term Memory (LSTM) model to detect the presence of the object.
A study presented at the IEEE International Conference on Development and Learning (ICDL) found that humans may possess a sand-sensing ability similar to that of shorebirds. Participants could detect a hidden cube beneath sand before touching it, discovering that human hands are far more sensitive than expected. Our ability to perceive tiny shifts in sand near buried objects, approaching the physical limits of detection, seems to be much more capable than we once thought.
do robots perform better than humans?
Surprisingly, humans outperformed the robot during experiments by around 30%. The researchers compared a robotic tactile sensor trained to match human performance while utilizing the LSTM algorithm for the robot, revealing that while humans achieved 70.7% accuracy, the robot produced several false positives, yielding only 40% overall precision.
“The discovery opens possibilities for designing tools and assistive technologies that extend human tactile perception,” said Zhengqi Chen, PhD, a 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, such as locating archaeological artifacts without damage, or exploring sandy or granular terrains, including Martian soil or ocean floors.”
“More broadly,” Chen added, “this research paves the way for touch-based systems that make hidden or hazardous exploration safer, smarter, and more effective.” Studies in this area, Chen and the team argue, are important as they reveal new dimensions of the known collection of human abilities.
“What makes this research especially exciting is how the human and robotic studies informed each other,” added Lorenzo Jamone, Associate Professor in Robotics & AI at University College London. ”The human experiments guided the robot’s learning approach, and the robot’s performance provided new perspectives for interpreting the human data.”
“It’s a great example of how psychology, robotics, and artificial intelligence can come together, showing that multidisciplinary collaboration can spark both fundamental discoveries and technological innovation,” Jamone added.”
The study, “Exploring Tactile Perception for Object Localization in Granular Media: A Human and Robotic Study,” appeared in IEEE Explore.
Chrissy Newton is a PR professional and the founder of VOCAB Communications. She currently appears on The Discovery Channel and Max and hosts the Rebelliously Curious podcast, which can be found on YouTube and on all audio podcast streaming platforms. Follow her on X: @ChrissyNewton, Instagram: @BeingChrissyNewton, and chrissynewton.com.