02570nas a2200325   4500008004100000022001400041245013800055210006900193260001200262300001100274490000800285520150800293653002601801653002601827653001601853653001301869653001101882653003101893100002001924700002301944700002001967700002001987700001802007700002302025700001902048700001902067700002402086700001902110856011502129       2020                        eng d  a1873-423500aBreathable, large-area epidermal electronic systems for recording electromyographic activity during operant conditioning of H-reflex.0 aBreathable largearea epidermal electronic systems for recording   c10/2020  a1124040 v1653 a<p>Operant conditioning of Hoffmann's reflex (H-reflex) is a non-invasive and targeted therapeutic intervention for patients with movement disorders following spinal cord injury. The reflex-conditioning protocol uses electromyography (EMG) to measure reflexes from specific muscles elicited using transcutaneous electrical stimulation. Despite recent advances in wearable electronics, existing EMG systems that measure muscle activity for operant conditioning of spinal reflexes still use rigid metal electrodes with conductive gels and aggressive adhesives, while requiring precise positioning to ensure reliability of data across experimental sessions. Here, we present the first large-area epidermal electronic system (L-EES) and demonstrate its use in every step of the reflex-conditioning protocol. The L-EES is a stretchable and breathable composite of nanomembrane electrodes (16 electrodes in a four by four array), elastomer, and fabric. The nanomembrane electrode array enables EMG recording from a large surface area on the skin and the breathable elastomer with fabric is biocompatible and comfortable for patients. We show that L-EES can record direct muscle responses (M-waves) and H-reflexes, both of which are comparable to those recorded using conventional EMG recording systems. In addition, L-EES may improve the reflex-conditioning protocol; it has potential to automatically optimize EMG electrode positioning, which may reduce setup time and error across experimental sessions.</p>10aBiosensing Techniques10aConditioning, Operant10aElectronics10aH-Reflex10aHumans10aReproducibility of Results1 aKwon, Young-Tae1 aNorton, James, J S1 aCutrone, Andrew1 aLim, Hyo-Ryoung1 aKwon, Shinjae1 aChoi, Jeongmoon, J1 aKim, Hee, Seok1 aJang, Young, C1 aWolpaw, Jonathan, R1 aYeo, Woon-Hong  uhttps://www.neurotechcenter.org/publications/2020/breathable-large-area-epidermal-electronic-systems-recording