A recent scientific study suggests that the human body may be able to detect the presence of hidden objects even before direct contact happens, especially in materials like sand. Does this mean we are like Spider-Man and we have some kind of super power? Not really, but that would be really cool. What this means is that the human tactile system may be far more sensitive and complex than previously believed.
It’s important to mention that the research was presented at the IEEE International Conference on Development and Learning and carried out by scientists from Queen Mary University of London and University College London. Now, we can start this article and see what this research found out in more detail. Let’s get started!
Finding hidden objects under the sand
Detecting buried objects in the sand is complicated because the sand is not like an average solid object or like a liquid. Instead, it’s formed with very tiny grains that transmit the strength in an irregular way, which is why when something is hidden under the surface, it can’t always be easily seen.
The most fascinating thing is that human touch system is interesting from the scientific point of view, but it can also be related to fields such as archaeology, rescue operations after disasters, or exploration tasks where digging blindly could damage objects or create dangerous situations.
Animals detecting objects without touching them
Before studying the human body to know how far ahead human touch can anticipate an object before actual contact occurs, scientists wanted to know how some birds did it. Basically, they send tiny mechanical disturbances in the grains of sand when something solid is nearby.
So, from these observations, researchers proposed the hypothesis that the human body could have a similar capacity.
No touching
To prove this hypothesis, scientists did an experiment with 12 participants. Each person introduced their index finger in a box full of dry sand and they moved the finger slowly following a path guided by LED lights. In some cases, there was a cube buried beneath the sand, and sometimes there was nothing.
So, while participants were following the path, they had to stop when they felt the presence of an object before touching it. The experimental design removed visual clues and controlled movement speed to make sure all participants experienced similar conditions.
Participants detected the object with a success rate of 70.7% at an average distance of about 6.9 centimeters before contact. This finding suggests that the human tactile system can recognize very subtle changes in the surrounding environment.
Humans v. Robots
Researchers also compared human performance with a robotic system designed to mimic the movement of a finger. The robot could detect objects at similar distances or even higher distances, but it made many more mistakes. While humans reached a precision of 70.7%, the robot achieved only 40% due to false detections.
Thanks to this comparison we can see that the human brain is very efficient when interpreting complex signals and distinguishing real information from background noise.
Hand and brain
The study explains that this capacity is not a mystery. What happens is that when the finger moves inside the sand, it creates a small displacement zone in front of it. So, if there’s an object within that area, the sand slightly changes the resistance and shape in which it transmits the pressure to the skin.
How does the skin and the brain interpret this? Basically, human skin contains mechanoreceptors that are capable of detecting extremely small changes in pressure and the brain interprets these patterns as signals that something is present ahead.
Limitations
The study has several important limitations:
- Only 12 young people took part in the study, which means the result doesn’t talk for the entire population.
- The experiment was made in a controlled environment and with slow and repetitive movements.
There’s no clue whether this capacity changes with the passage of time, experience, training, or manual skill, and if the same effect occurs in materials other than dry sand or in real-world situations where movements are less predictable. So, we’ll have to keep waiting until we know more about this capacity we humans have.