Researchers learn the language of the nervous system

Researchers at the Swiss Federal Institute of Technology in Zurich (ETH), working with colleagues from Germany, Serbia and Russia, have successfully changed the signals transmitted by neuroprosthetics so that they are similar to those of the missing body part. According to a recently published study, the results of this neuroscience-driven technology inspired by the human body could be “a model for the development of novel assistive neurotechnologies.” This could be relevant for arm and leg prostheses, as well as spinal implants and electrodes for brain stimulation.

Several years ago, the research team led by Stanisa Raspopovic from the Neuroengineering Lab at ETH developed prosthetic legs that enabled amputees to feel sensations from the artificial body part for the first time. Their neuroprosthetics were connected to the sciatic nerve in the thigh via implanted electrodes. However, they were not yet able to evoke natural sensations, explains Raspopovic in a press release issued by ETH.

He and his team are therefore using biomimetic stimulation – natural signals that can write physiologically plausible information back into the residual healthy nervous system. Doctoral student Natalija Katic developed a computer model called FootSim for this purpose, based on data from a Canadian study that recorded the activity of mechanoreceptors in the soles of the feet of healthy test subjects.

These data were used to generate biomimetic signals. The researchers initially used experiments with cats to prove that biomimetic stimulation is superior to time-constant stimulation and less taxing on the brain, and then followed this up with a clinical study with leg amputees. ce/mm