Immediate and long-term effects of BCI-based rehabilitation of the upper extremity after stroke: a systematic review and meta-analysis

Abstract

Background: A substantial number of clinical studies have demonstrated the functional recovery induced by the use of brain-computer interface (BCI) technology in patients after stroke. The objective of this review is to evaluate the effect sizes of clinical studies investigating the use of BCIs in restoring upper extremity function after stroke and the potentiating effect of transcranial direct current stimulation (tDCS) on BCI training for motor recovery. Methods: The databases (PubMed, Medline, EMBASE, CINAHL, CENTRAL, PsycINFO, and PEDro) were systematically searched for eligible single-group or clinical controlled studies regarding the effects of BCIs in hemiparetic upper extremity recovery after stroke. Single-group studies were qualitatively described, but only controlled-trial studies were included in the meta-analysis. The PEDro scale was used to assess the methodological quality of the controlled studies. A meta-analysis of upper extremity function was performed by pooling the standardized mean difference (SMD). Subgroup meta-analyses regarding the use of external devices in combination with the application of BCIs were also carried out. We summarized the neural mechanism of the use of BCIs on stroke. Results: A total of 1015 records were screened. Eighteen single-group studies and 15 controlled studies were included. The studies showed that BCIs seem to be safe for patients with stroke. The single-group studies consistently showed a trend that suggested BCIs were effective in improving upper extremity function. The meta-analysis (of 12 studies) showed a medium effect size favoring BCIs for improving upper extremity function after intervention (SMD = 0.42; 95% CI = 0.18-0.66; I 2 = 48%; P < 0.001; fixed-effects model), while the long-term effect (five studies) was not significant (SMD = 0.12; 95% CI = − 0.28-0.52; I 2 = 0%; P = 0.540; fixed-effects model). A subgroup meta-analysis indicated that using functional electrical stimulation as the external device in BCI training was more effective than using other devices (P = 0.010). Using movement attempts as the trigger task in BCI training appears to be more effective than using motor imagery (P = 0.070). The use of tDCS (two studies) could not further facilitate the effects of BCI training to restore upper extremity motor function (SMD = − 0.30; 95% CI = − 0.96-0.36; I 2 = 0%; P = 0.370; fixed-effects model).

A Virtual Reality Muscle–Computer Interface for Neurorehabilitation in Chronic Stroke: A Pilot Study

“…For the FMA-UE, we again found improvement in three of four participants, but now two showed clinically meaningful differences (7 and 8 points). In fact, on average, there was a 4.5 point improvement in FMA-UE, which even compares well to longer training interventions [6].…”

“…Brain-computer interfaces (BCIs) that trigger game activity upon detection of movement-related brain signals, measured via electroencephalography (EEG), have received much attention over the last two decades [6,7]. These systems do not require active, volitional movement and can often just be driven by the imagination of movement, allowing them to be of benefit to those whose severe deficits preclude direct reinforcement of overt movement by closing the loop between the brain and the environment [8,9].…”

Portable rehabilitation system with brain-computer interface for inpatients with acute and subacute stroke: A feasibility study

“…This mechanism may contribute to the recovery of motor function from hemiplegia after stroke. In fact, a recent BCI meta-analysis (Bai et al, 2020) showed that BCIs combined with neuromuscular electrical stimulation may be a better combination for functional recovery than other kinds of neurofeedback.…”

Why we should systematically assess, control and report somatosensory impairments in BCI-based motor rehabilitation after stroke studies

“…This paper offers a theoretical analysis, based on the literature, to answer these questions. Because BCIs have proven promising for upper limb rehabilitation ( Cervera et al, 2018 , Bai et al, 2020 ), we chose to focus on strokes affecting motor abilities of the upper limb, e.g., hemiplegia or hemiparesis.…”