Medical News Observer

Key Points:

• The prosthetic leg’s connection to the sciatic nerve through implanted electrodes allows for real-time sensory feedback, improving users’ confidence and mobility, especially on challenging terrains.
• Introducing a biomimetic neurostimulation framework aims to overcome the limitations of traditional neuroprosthetics, which often induce artificial sensations.
• Initial experiments with cats and tests within a bionic device show that biomimetic neuromodulation closely mirrors natural neural responses, promising a substantial improvement in prosthetic functionality and user experience.

Earlier researchers at ETH Zurich Neuroengineering Lab created a prosthetic leg that could connect to the sciatic nerve through implanted electrodes, enabling amputees to feel sensations from the artificial limb. This connection facilitated communication between the neuroprosthesis and the brain, transmitting real-time feedback on changes in pressure on the prosthetic foot’s sole during movement.

Need for a biomimetic neurostimulation framework.

This innovation gave users a more natural sense of their prosthetic, enhancing their confidence and mobility, particularly on challenging terrains. Researchers highlighted that current neuroprosthetics typically induce artificial and unpleasant sensations due to their reliance on time-constant electrical pulses, a method deemed unnatural and inefficient.

This study introduces a biomimetic neurostimulation framework designed to provide a more intuitive and natural sensory experience for individuals with sensorimotor deficits, addressing the limitations of traditional artificial communication methods with the brain through peripheral nerve stimulation.

FootSim – Computational model

To address these challenges and improve the fidelity of sensory feedback, researchers developed a computational model named FootSim. This model, inspired by recordings of mechanoreceptors in the human foot, simulates the dynamic activation of these sensory receptors during walking or running. This innovative approach aims to replicate the natural neural signals transmitted to the brain, promising a more natural and effective neurostimulation method.

Animal Study

Further research involving experiments with cats demonstrated that biomimetic signals closely mimic the natural patterns of neural activity, in contrast to the disjointed patterns produced by traditional stimulation methods. 

Results With Neuroprosthetics

The results show that biomimetic neuromodulation leads to neural responses closely mirroring natural dynamics, significantly improving mobility and reducing mental effort in patients when tested within a bionic device.

Implications

These findings underscore the potential of biomimetic stimulation to enhance the functionality of neuroprosthetics, reducing the incidence of unpleasant sensations and improving users’ overall quality of life. This approach, grounded in neuroscience and inspired by the human body’s natural processes, suggests a promising direction for enhancing assistive neurotechnologies.

Reference

Valle, Giacomo, Natalija Katic Secerovic, Dominic Eggemann, Oleg Gorskii, Natalia Pavlova, Francesco M. Petrini, Paul Cvancara, et al. 2024. “Biomimetic Computer-to-Brain Communication Enhancing Naturalistic Touch Sensations via Peripheral Nerve Stimulation.” Nature Communications 15 (1): 1151. https://doi.org/10.1038/s41467-024-45190-6.