Abstract 154: Changes in Task fMRI After Stroke Rehabilitation Using Closed-Loop Neurofeedback

Introduction: Brain-computer interface (BCI) is an emerging technology for stroke rehabilitation, but little is known about brain changes associated with its use. We examine changes in laterality index (LI) and functional connectivity (FC) during hand movements associated with BCI interventional therapy. Methods: We collected anatomical and functional MRI of 8 stroke patients with upper extremity motor impairment before, during, and after up to 6 weeks of therapy using a BCI system with tongue and functional electrical stimulations. We acquired functional images during imagined (MI) and executed (ME) tapping and squeezing of each hand; not all subjects performed all tasks. Two subjects’ scans were flipped so that as a group the lesion was left (L) and the impaired limb right (R). We computed LI using 3 mask sets: whole brain, motor network, and motor cortex. Group-level analyses examined FC changes to motor network seeds using AFNI and Matlab NBS toolbox. Results: BCI intervention led to decreased average LI during tapping. Overall, R taps shifted L to bilateral; all L taps shifted bilateral to R. Trends were consistent across all masks at thresholds p Conclusions: BCI interventional therapy of the impaired hand leads to more bilateral brain activity, while more lateralized activation was seen of the unimpaired hand to its corresponding contralateral motor regions. With different patterns of change observed during tasks using the impaired or unimpaired hand, lesioned brain areas may respond differently to BCI than unlesioned counterparts.