Brain–computer interface based on functional near-infrared spectroscopy integrated with plantar load simulator in post-stroke rehabilitation: a pilot study

Introduction. Gait disorders are a common and severe consequence of stroke, limiting patient autonomy and quality of life. A functional near-infrared spectroscopy (NIRS)-based brain–computer interface (BCI) represents a promising technology for restoring motor functions; however, its application in gait rehabilitation remains insufficiently studied. Study aim: To evaluate the clinical applicability and technical feasibility of an NIRS-based BCI technology combined with a pneumatic plantar support load simulator (pneumatic orthosis) as an adjunct to comprehensive motor rehabilitation in post-stroke patients. Materials and methods. Seventeen patients were enrolled in the pilot study, of whom 15 (median age 58.0 [47.0; 64.0] years, median time since stroke 6.0 [3.0; 9.0] months) completed a course of 7–13 (median 10 [9; 10]) training sessions with the NIRS-BCI–pneumatic orthosis technology in addition to a comprehensive motor rehabilitation program. Motor function was assessed using the Fugl–Meyer Assessment scale for the lower extremity, the 10-Meter Walk Test, and the Timed Up and Go test. Results. A total of 147 NIRS-BCI–pneumatic orthosis training sessions were conducted, with a total median exposure of 229 minutes per patient. The median BCI classifier recognition rate for patients’ mental states was 54.93% [53.10; 69.70]. The median of the maximum achieved recognition rates was 75.57% [67.54; 87.14]. Characteristic hemodynamic activation patterns were identified in motor and associative cortical areas. Following the course, statistically significant improvements were noted on the Fugl–Meyer Assessment scale (from 19.0 [16.0; 24.0] to 24.0 [20.0; 25.0] points; p = 0.001) and the Timed Up and Go test (from 17.61 [14.21; 22.34] to 16.06 [13.00; 17.41] s; p = 0.041), but not on the 10-Meter Walk Test (p 0.05). Most patients tolerated the procedures satisfactorily; two participants withdrew early. Conclusion. The clinical applicability and technical feasibility of the NIRS-BCI–pneumatic orthosis technology for post-stroke gait rehabilitation have been confirmed. Randomized controlled trials are required to assess its clinical efficacy.