Abstract TP60: Stroke Recovery Using Brain Computer Interface

Abstract

Introduction: Non-invasive electroencephalographic (EEG) based brain-computer interface (BCI) therapy has been shown to increase upper extremity mobility in stroke survivors with persistent upper extremity motor impairment. Previous studies have shown that in order to evoke movement from a particular motor system, sensory cues are combined in an essentially linear model. That is, the feedback from each sensory system is summed and torque is generated as a function of the summed signal. This subanalysis aims to evaluate the efficacy of EEG-based BCI-functional electrical stimulation (FES). The goal was to determine whether greater sensory feedback improves BCI task performance in stroke survivors with upper extremity motor impairment. Methods: Data were acquired from 31 ischemic stroke patients, with persistent upper extremity motor impairment (mean age = 66 years old, F = 14, M = 17, mean time since stroke onset = 100 months). Participants were kept in one group and all patients received two types of therapies: BCI-only therapy followed by BCI-FES therapy. Participants were instructed to move either their left or right hand to control a virtual cursor in a cursor and target task. A successful trial was recorded if the participant successfully moved the cursor into the target area. The task was first performed with only visual stimulation, then participants received cutaneous stimulation via the paired FES in addition to the visual display of the cursor and target. EEG data was acquired using BCI2000 software and a 16 channel EEG cap. Results: Although improvement was seen for participants when they received BCI therapy as well as when they received BCI-FES therapy, BCI performance scores over time were not significantly different from one another (p = 0.13). The BCI-only and BCI-FES pre-study averages were 5.58 (SD = 1.64) and 5.86 (SD = 1.66) respectively and the post-study averages were 5.99 (SD = 1.41) and 6.33 (SD = 1.75) respectively. Conclusions: For chronic stroke survivors, both BCI visual only and BCI-FES intervention may help promote restoration of upper extremity motor function at similar rates.