Amputee can feel the heat of touch with bionic technology – 05/21/2023 – Equilibrium and Health

Fabrizio Fidati, who had his right hand amputated in an accident 25 years ago, had not experienced the sensation of temperature in his missing fingers until tests for a bionic technology unlocked for him the coolness of ice water and the heat of a stove burner. .

Eventually, the researchers hope this could lead to loved ones feeling more natural when he is wearing his prosthesis.

With thermal electrodes placed on the skin of the residual limbs, amputees like Fidati have reported feeling hot or cold in their phantom hands and fingers, as well as directly on the upper arm, according to trials at the École Polytechnique Federal de Lausanne (EPFL) in Switzerland.

The 59-year-old Italian is among 27 amputees who have taken part in the trials, with 17 of them reporting successful results.

“The first time I participated in the experiment, I felt like I had rediscovered sensation in my phantom hand,” he said.

Test takers were also able to differentiate between plastic, glass and copper, pinpointing where they got the sensations on images of a hand.

“By stimulating specific parts of the amputees’ residual arm, we were able to induce sensation in the lost phantom hands,” said Solaiman Shokur, senior scientist neuroengineer at EPFL and one of the leaders of the study, published in the journal Science.

“What they feel in this phantom hand is similar to what they feel in their intact hand.”

A woman who also participated in the study, Francesca Rossi, said that she had already felt tingling in her missing hand when she touched the tip of her arm, but said: “Feeling the temperature variation is a different thing, something important … something beautiful.” .

The technology, which has been tested for over two years, does not need to be deployed. It can be used on the skin and combined with a common prosthesis.

Silvestro Micera, who led the study with Shokur, said they now want to test the device on a larger scale, before combining it with other technologies to improve tactile sensations in amputees.

“We thought we could give people a better sense of embodying their hands and maybe even give them the ability to feel their loved ones in a much more natural way,” added Shokur.

Fidati said that in addition to helping amputees with everyday tasks like cooking, technology could open the door for him to feel the warmth of others.

“There is also a social aspect that is important,” he said. “When I meet someone and shake their hand, I expect to feel warm.”

Micera, professor at the EPFL and Sant’Anna School of Advanced Studies, said: “Temperature feedback is essential to transmit information that goes beyond touch, it leads to feelings of affection. We are social beings, and warmth is an important part of from that.”