Biomimetic computer-to-brain communication restoring naturalistic touch sensations via peripheral nerve stimulation
Artificial communication with the brain through peripheral nerve stimulation recently showed promising results in people with sensorimotor deficits. However, these efforts fall short in delivering close-to-natural rich sensory experience, resulting in the necessity to propose novel venues for converting sensory information into neural stimulation patterns, which would possibly enable intuitive and natural sensations. To this aim, we designed and tested a biomimetic neurostimulation framework inspired by nature, able "to write" physiologically plausible information back into the residual healthy nervous system. Starting from the in-silico model of mechanoreceptors, we designed biomimetic policies of stimulation, emulating the activity of different afferent units. Then, we experimentally assessed these novel paradigms, alongside mechanical touch and commonly used, linear neuromodulations. We explored the somatosensory neuroaxis by stimulating the nerve while recording the neural responses at the dorsal root ganglion and spinal cord of decerebrated cats. Biomimetic stimulation resulted in a neural activity that travels consistently along the neuroaxis, producing the spatio-temporal neural dynamic more like the naturally evoked one. Finally, we then implemented these paradigms within the bionic device and tested it with patients. Biomimetic neurostimulations resulted in higher mobility and decreased mental effort compared to traditional approaches. The results of this neuroscience-driven technology inspired by the human body could be a model for the development of novel assistive neurotechnologies.