A closed-loop brain–computer interface triggering an active ankle–foot orthosis for inducing cortical neural plasticity - Xu, Ren; Jiang, Ning; Mrachacz-Kersting, Natalie; Lin, Chuang; Prieto, Guillermo Asín; Moreno, Juan C; Pons, Jose L; Dremstrup, Kim; Farina, Dario (IEEE Transactions on Biomedical Engineering, 2014)