Bimodal EEG-fMRI neurofeedback for stroke rehabilitation: A case report

Abstract

Neurofeedback (NF) consists on training self-regulation of brain activity by providing real-time information about the participant brain function. Few works have shown the potential of NF for stroke rehabilitation however its effectiveness has not been investigated yet. NF approaches are usually based on real-time monitoring of brain activity using a single imaging technique. Recent studies have revealed the potential of combining EEG and fMRI to achieve a more efficient and specific self-regulation, which may be critical in clinical applications. In this case report, we tested the feasibility of applying bimodal EEG-MRI NF on stroke patients. Two chronic patients affected by left hemiplegia (subcortical lesion) participated. The protocol included a calibration step (motor imagery of hemiplegic hand) and two NF sessions (5 minutes each). The experiment was run using a NF platform performing real-time EEG-fMRI processing and NF presentation ( Fig. 1 ). The NF metaphor consisted of a ball moving on a gauge proportionally to the average BOLD and EEG activity in regions of interest (ROI) identified over the ipsilesional motor cortex during calibration. Both patients were able to self-regulate their brain activity during the NF sessions. The EEG activity was harder to modulate than the BOLD activity ( Fig. 2 , Fig. 3 ). The correlation of the BOLD signal with the task varied depending on the ROI targeted and was particularly high for the supplementary motor area. The patients were highly motivated to engage and satisfied with the NF animation, as assessed with a qualitative questionnaire. We performed two NF experiments involving chronic stroke patients: preliminary results showed the feasibility and the potential of applying EEG-fMRI NF for stroke rehabilitation.