Long-term effect on EEG sensorimotor responsiveness to motor imagery after a BCI training for stroke rehabilitation

Previous studies demonstrated the efficacy of EEG-Brain-Computer Interfaces based on Motor Imagery (MI-BCI) in post stroke functional motor recovery of upper limbs [1]; however, the maintenance of such effects in the long-term is still partially unexplored. Here we tackled this long-term aspect of MI-BCI induced positive effects on rehabilitation outcomes by analyzing an EEG dataset acquired from subacute stroke patients recruited in the longitudinal Randomized Controlled Trial reported in [2]. The oscillatory activity in the EEG beta band known as related to MI tasks within BCI contexts [1], [3], was studied at different time points in two groups of participants one performing MI practice with BCI assistance (BCI group) while the other performing MI training alone (CTRLgroup). [1] F. Pichiorri et al., “Brain-computer interface boosts motor imagery practice during stroke recovery,” Ann. Neurol., vol. 77, no. 5, pp. 851–865, 2015, doi: 10.1002/ana.24390. [2] D. Mattia et al., “The Promotoer, a brain-computer interface-assisted intervention to promote upper limb functional motor recovery after stroke: A study protocol for a randomized controlled trial to test early and long-term efficacy and to identify determinants of response,” BMC Neurol., vol. 20, no. 1, pp. 1–13, 2020, doi: 10.1186/s12883-020-01826-w. [3] F. Pichiorri et al., “Sensorimotor rhythm-based brain-computer interface training: The impact on motor cortical responsiveness,” J. Neural Eng., vol. 8, no. 2, 2011, doi: 10.1088/1741-2560/8/2/025020.