PT  - JOURNAL ARTICLE
AU  - Earley, Eric J.
AU  - Berneving, Anton
AU  - Zbinden, Jan
AU  - Ortiz-Catalan, Max
TI  - Neurostimulation Artifact Removal for Implantable Sensors Improves Signal Clarity and Decoding of Motor Volition
AID  - 10.1101/2022.09.07.506955
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.09.07.506955
4099  - http://biorxiv.org/content/early/2022/09/09/2022.09.07.506955.short
4100  - http://biorxiv.org/content/early/2022/09/09/2022.09.07.506955.full
AB  - As the demand for prosthetic limbs with reliable and multi-functional control increases, recent advances in myoelectric pattern recognition and implanted sensors have proven considerably advantageous. Additionally, sensory feedback from the prosthesis can be achieved via stimulation of the residual nerves, enabling closed-loop control over the prosthesis. However, this stimulation can cause interfering artifacts in the electromyographic (EMG) signals which deteriorate the reliability and function of the prosthesis. Here, we implement two real-time stimulation artifact removal algorithms, Template Subtraction and ε-Normalized Least Mean Squares, and investigate their performance in offline and real-time myoelectric pattern recognition in two transhumeral amputees implanted with nerve cuff and EMG electrodes. We show that both algorithms are capable of significantly improving signal-to-noise ratio and offline pattern recognition accuracy of artifact-corrupted EMG signals. Furthermore, both algorithms improved real-time decoding of motor intention during active neurostimulation. Although these outcomes are dependent on the user-specific sensor locations and neurostimulation settings, they nonetheless represent progress towards bi-directional neuromusculoskeletal prostheses capable of multifunction control and simultaneous sensory feedback.Competing Interest StatementThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. MOC has been consultant for Integrum AB, and the rest of the authors declare no conflict of interest.