Scientists have made a groundbreaking discovery in the field of prosthetics, as they have developed a device called MiniTouch that enables amputees to experience warmth in their phantom hand.
This innovative technology involves a small sensor placed on a prosthetic finger and electrodes that simulate sensations on the residual arm. By relaying the temperature of the object being touched, the electrodes create the illusion of warmth or coolness in the missing fingers.
This breakthrough, outlined in a study published in the journal Science, could revolutionize the design of prosthetic limbs by incorporating temperature-sensing capabilities without invasive procedures.
The development of MiniTouch stemmed from an unexpected finding that amputees are somehow able to perceive temperatures in their missing hand. Dr. Solaiman Shokur, a neuroengineer and scientist at Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland, described this phenomenon as the “thermal phantom sensation.”
Typically, when a hot or cold object is placed on an able-bodied person’s forearm, they feel the temperature directly on their skin. However, in amputees, this temperature sensation is experienced in the phantom limb, or the absent hand.
During tests conducted by the researchers, they anticipated that amputees would indicate the location and perceived temperature on their residual limb when presented with temperature sensations. But, to their surprise, the participants pointed to a drawing of a hand in front of them and explained that they felt the sensations there. This discovery was pivotal in developing a neurotechnology capable of integrating with prosthetic hands.
The team successfully tested the bionic technology, MiniTouch, on 17 out of 27 patients. This device utilizes information about an object’s heat-conducting properties to determine its temperature. The scientists discovered that specific areas of the amputated arm’s skin can project temperature sensations to corresponding parts of the phantom hand, such as the thumb or the tip of an index finger. Moreover, they found that these temperature perceptions vary from patient to patient, making the experience unique to each individual.
The amputees involved in the study expressed their delight in being able to feel the limb once again, as temperature feedback contributes to a more complete sense of having a physical limb.
With further advancements in this field, we can expect even more remarkable innovations that bridge the gap between human perception and advanced prosthetic technology.