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Background: Functional Electrical Stimulation (FES) represents a promising technique for promoting functional recovery in individuals with neuromuscular diseases. Traditionally, current pulses are delivered through self‐adhesive hydrogel Ag/AgCl electrodes, which allow a good contact with the skin, are easy‐to‐use and have a moderate cost. However, skin adherence decreases after a few uses and skin irritations can originate. Recently, textile electrodes have become an attractive alternative as they assure increased durability, easy integration into clothes and can be conveniently cleaned, improving the wearability of FES. However, as various manufacture processes were attempted, their clear validation is lacking. This proof‐of‐concept study proposes a novel set of ink‐based printed textile electrodes and compares them to adhesive hydrogel electrodes in terms of impedance, stimulation performance and perceived comfort. Methods: The skin–electrode impedance was evaluated for both types of electrodes under different conditions. These electrodes were then used to deliver FES to the Rectus Femoris of 14 healthy subjects to induce its contraction in both isometric and dynamic conditions. This allowed to compare the two types of electrodes in terms of sensory, motor, maximum and pain thresholds, FES‐induced range of motion during dynamic tests, FES‐induced torque during isometric tests and perceived stimulation comfort. Results: No statistically significant differences were found both in terms of stimulation performance (Wilcoxon test) and comfort (Generalized Linear Mixed Model). Conclusion: The results showed that the proposed ink‐based printed textile electrodes can be effectively used as alternative to hydrogel ones. Further experiments are needed to evaluate their durability and their response to sterilizability and stretching tests. [ABSTRACT FROM AUTHOR]

The physical boundaries of our body do not define what we perceive as self. This malleable representation arises from the neural integration of sensory information coming from the environment. Manipulating the visual and haptic cues produces changes in body perception, inducing the Full Body Illusion (FBI), a vastly used approach to exploring humans' perception. After pioneering FBI demonstrations, issues arose regarding its setup, using experimenter-based touch and pre-recorded videos. Moreover, its outcome measures are based mainly on subjective reports, leading to biased results, or on heterogeneous objective ones giving poor consensus on their validity. To address these limitations, we developed and tested a multisensory platform allowing highly controlled experimental conditions, thanks to the leveraged use of innovative technologies: Virtual Reality (VR) and Transcutaneous Electrical Nerve Stimulation (TENS). This enabled a high spatial and temporal precision of the visual and haptic cues, efficiently eliciting FBI. While it matched the classic approach in subjective measures, our setup resulted also in significant results for all objective measurements. Importantly, FBI was elicited when all 4 limbs were multimodally stimulated but also in a single limb condition. Our results behoove the adoption of a comprehensive set of measures, introducing a new neuroscientific platform to investigate body representations., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Preatoni et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

This case study was designed starting from our experience at CYBATHLON 2020. The specific aim of this work was to compare the effectiveness of different fatigue reducing stimulation strategies during cycling induced by Functional Electrical Stimulation (FES). The compared stimulation strategies were: traditional constant frequency trains (CFTs) at 30 and 40Hz, doublet frequency trains (DFTs) and spatially distributed sequential stimulation (SDSS) on the quadriceps muscles. One Spinal Cord Injured (SCI) subject (39 years, T5-T6, male, ASIA A) was involved in 12 experimental sessions during which the four strategies were tested in a randomized order during FES-induced cycling performed on a passive trike at a constant cadence of 35 RPM. FES was delivered to four muscle groups (quadriceps, gluteal muscles, hamstrings and gastrocnemius) for each leg. The performance was evaluated in terms of saturation time (i.e., the time elapsed from the beginning of the stimulation until the predetermined maximum value of current amplitude is reached) and root mean square error (RMSE) of the actual cadence with respect to the target value. SDSS achieved a statistical lower saturation time and a qualitative higher RMSE of the cadence with respect to CFTs both at 30 and 40Hz.Clinical relevance- Conversely to previous literature, SDSS seems to be ineffective to reduce muscle fatigue during FES-induced cycling. Further experiments are needed to confirm this result.