Application of a therapy with functional electrical stimulation coupled with a brain-computer interface system based on P300 for rehabilitation of the paretic upper extremity in individuals with chronic stroke.

Abstract

Introduction
Stroke is one of the leading causes of disability worldwide. Motor sequelae, especially in the upper extremity, are common and severe, limiting patients' ability to perform basic activities of daily living. Conventional physical therapy has variable effectiveness, especially in patients with moderate and severe sequelae. This situation raises the need to explore alternative methods that promote neuroplasticity and improve the quality of life of these individuals. At INRLGII we have developed a functional electrical stimulation (FES) device coupled to a P300 potential-based brain-computer interface (BCI) and have demonstrated, in a pilot study, its feasibility and possible beneficial effect. Hence our research question: What is the effect of BCI-FES therapy for the rehabilitation of the paretic upper limb in individuals with chronic stroke? We hypothesize that the effect will be greater than with conventional therapy.

Objective
Evaluate the effect of a therapeutic protocol combining P300-based BCI-FES in the rehabilitation of the paretic upper extremity in patients with chronic stroke.

Methodology
A randomized, single-blind, controlled clinical trial is being conducted. Preliminary results of the experimental group are presented. Upper extremity function was evaluated with the Arm Research Test (ARAT), performance impairment with the Fugl-Meyer assessment (FMA), Functional Independence Measure (FIM), and spasticity with the Modified Ashworth Scale (MAS), both at the beginning and at the end of the therapy. The scores obtained were compared using the Wilcoxon statistical test for paired samples.

Results
100% of the subjects were men with an average age of 52.8 years (SD: 18.2) and an evolution time of 25 months (SD: 40.8). Regarding stroke, 80% were ischemic and 20% were mixed. Regarding comorbidities, 60% had hypertension, 60% had diabetes mellitus, and 40% had a history of smoking. After BCI-FES therapy, statistically significant differences were found in the FMA scales with an increase in the mean score from 28.4 to 44.6 (p <0.001), ARAT with an increase from 21.2 to 33.6 (p = 0.001) and FIM with an increase from 102.4 to 118.6 (p <0.001).

Conclusions
The findings of this study indicate that P300 potential-based FES-BCI therapy can be an effective intervention to improve motor recovery of the upper extremity, functionality, and functional independence in individuals with chronic stroke, even in the presence of comorbidities such as DM and HAS. The inclusion of a larger number of participants and the consideration of patients with hemorrhagic CVD in future studies would allow a more complete evaluation of the efficacy of BCI-FES therapy.