Pain demands to be felt as the saying goes. Pain may not be pleasing, but it’s necessary for survival. A complex protection device, pain is our body’s way of showing us that something’s incorrect and that we should take an urgent response to avoid damage. Skin — the body’s biggest organ — is constantly monitoring for pain. It can trigger pain-avoiding reactions involuntarily through reflexes, for example when we touch something hot.

At the moment, scientists at RMIT University in Melbourne, Australia, have produced an unnatural skin that copies this mechanism and acts to pain stimuli. They used silicone rubber to make it; it has the feeling of actual skin and is also “very similar to the skin in its building properties,” mentions Madhu Bhaskaran, an engineering professor at RMIT University and the project’s head researcher. It could commence innovative discoveries in robotics and prosthetics.

Similar to the actual skin, the synthetic version is created to respond when pressure, heat or cold exceed a pain threshold. Its external layers sandwich electronic circuits studded with sensors, which respond to stimuli. “The enthralling thing about our body is that it functions by sending electrical signs into the central nervous system,” states Bhaskaran. Electronic circuits work in the same way, and are just as quick, she describes.

When we feel something scorching hot, pain receptors in our skin transfer an electrical signal through our nerves to the brain. The brain sends its own electrical signal to begin a response — for instance a withdrawal reflex to move the afflicted arm off from the hotness. In much the same way, when one of the sensors in the synthetic skin detects a pain stimulus, it transfers an electrical sign to the brain-mimicking parts of the composition, Bhaskaran tells. This can be programmed to cause a change.