Stroke, Upper Limb Rehabilitation
Conditions
Keywords
Brain-machine interface, Neuroplasticity, Physical therapy, Stroke Rehabilitation, Upper-limb recovery
Brief summary
Stroke can lead to long-term impairment of upper-limb function, particularly in the chronic phase, where recovery is often limited. Brain-computer interface (BCI) systems combined with motor imagery (MI) are emerging as promising neurorehabilitation approaches. Providing real-time neurofeedback during MI may enhance motor recovery by promoting use-dependent neuroplasticity; however, evidence in individuals with chronic stroke remains limited. This controlled pilot study aims to evaluate the feasibility and preliminary effects of an EEG-based BCI neurofeedback intervention combined with MI and physiotherapy on upper-limb motor function and brain activation patterns in individuals with chronic stroke. Participants are assigned to either an experimental group receiving MI with real-time EEG-based neurofeedback or a control group receiving MI with sham feedback, alongside a standardized four-week physiotherapy program. Motor function is assessed using validated clinical measures, including the Action Research Arm Test, Fugl-Meyer Assessment, Motor Assessment Scale, and grip strength, with changes interpreted according to clinically meaningful thresholds. Neurophysiological changes are explored through EEG-based measures of brain symmetry and task-related functional MRI. It is expected that participants receiving real neurofeedback will show greater improvements in upper-limb function and more adaptive brain activation patterns compared to those receiving sham feedback. Findings from this study will help determine the feasibility of this approach and inform the design of larger trials to evaluate its effectiveness in chronic stroke rehabilitation.
Detailed description
This study follows a double-blind design in which both participants and outcome assessors are unaware of group allocation, minimizing potential sources of bias. The inclusion of a sham feedback condition is intended to control for nonspecific effects related to task engagement, attention, and exposure to the intervention environment. The neurofeedback protocol is based on real-time modulation of EEG-derived sensorimotor rhythms during motor imagery tasks. In the experimental group, feedback is contingent on participants' brain activity, enabling reinforcement of targeted neural patterns. In the control group, feedback is non-contingent but visually similar, ensuring maintenance of blinding. To ensure intervention fidelity, the protocol is delivered over a fixed duration with standardized procedures across participants. The integration of the neurofeedback intervention within a structured rehabilitation schedule is designed to minimize variability and support consistency in delivery. Outcome interpretation incorporates minimal clinically important difference (MCID) thresholds to distinguish clinically meaningful improvements. In addition, the combined use of EEG and task-related functional MRI provides complementary insight into neuroplasticity, capturing both temporal dynamics and spatial patterns of brain reorganization. Feasibility is further evaluated through indicators such as adherence to the intervention protocol, participant retention, and the practicality of implementing EEG-based neurofeedback in a rehabilitation context. These elements are intended to inform protocol optimization and the design of future randomized controlled trials.
Interventions
OTHERMotor imagery-based training - Real Neurofeedback
Participants completed 12 sessions of motor imagery (MI)-based training (30 minutes/session, 3× weekly) using an EEG-based BCI system (Emotiv® EPOC headset, 14 channels). During each session, participants imagined moving their right or left hand to push a virtual ball, guided by directional cues. Real-time neurofeedback of the ball movement was provided contingent on participants' brain activity. Each MI session was followed by a standardized physiotherapy session based on a problem-solving therapeutic model.
OTHERMotor imagery-based training - Sham Neurofeedback
Participants completed 12 sessions of motor imagery (MI)-based training (30 minutes/session, 3× weekly) using an EEG-based BCI system (Emotiv® EPOC headset, 14 channels). Participants completed the same MI-based training and physiotherapy schedule. During MI, they received sham feedback: pre-recorded visual feedback from previous sessions, not contingent on their brain activity. All other procedures, including trial structure, session frequency, and physiotherapy, were identical to the experimental group.
Sponsors
CESPU-Escola Superior de Tecnologias da Saúde de Tâmega e Sousa
ICVS - Life and Health Sciences Research Institute
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
The study design includes double blinding, in which participants and outcome assessors are unaware of group allocation. This approach minimizes potential bias from expectation effects, observer influence, or differences in engagement between groups.
Intervention model description
This is a parallel assignment interventional study in which participants with chronic stroke are randomly assigned to one of two groups: (1) experimental group receiving motor imagery with real-time EEG-based brain-computer interface (BCI) neurofeedback, or (2) control group receiving motor imagery with sham feedback. Both groups undergo the same standardized physiotherapy program. Participants and outcome assessors are double-blinded to minimize bias. Each participant receives only one type of intervention throughout the four-week study period, allowing direct comparison of effects between real and sham neurofeedback while maintaining consistent training conditions.
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* Adults aged ≥18 years * First-ever cortical ischemic stroke affecting the left middle cerebral artery (MCA) territory * ≥12 months since stroke onset * Stroke diagnosis confirmed by structural neuroimaging (MRI or CT) * Lesion localization confirmed based on clinical and radiological criteria
Exclusion criteria
* Complete hand plegia * Presence of language or cognitive impairment, as assessed by the Montreal Cognitive Assessment (MoCA) * Presence of attentional deficits * Presence of visual impairments that may interfere with task performance * Diagnosis of depression * Pre-stroke dependence in activities of daily living * Left-handedness, as assessed by the Edinburgh Handedness Inventory * Inability to perform motor imagery tasks * Contraindications to MRI (e.g., metallic implants, implanted electronic devices, or claustrophobia)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Neuroplasticity | Pre- and post-intervention (4 weeks) | Assessed using combined EEG-fMRI measures. EEG was recorded with a 64-channel MRI-compatible system during motor execution (ME) and motor imagery (MI) tasks for both hands, with simultaneous fMRI acquisition. Brain symmetry index (BSI) was computed from mu (8-13 Hz) and beta (14-30 Hz) band activity in ipsilesional (C1, C3, FC1, FC3) and contralesional (C2, C4, FC2, FC4) motor cortical regions. fMRI data were acquired on a 3.0 Tesla scanner and analyzed using standard preprocessing and SPM8 to evaluate functional activation patterns. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Upper-limb motor function - Action Research Arm Test (ARAT) | Pre- and post-intervention (4 weeks) | Functional assessment of upper-limb dexterity. Scored independently by two blinded raters from video recordings. Score range: 0 to 57. Direction: Higher scores indicate better upper limb function. |
| Upper-limb motor function - Fugl-Meyer Assessment - Upper Extremity. (FMA-UE) | Pre- and post-intervention (4 weeks) | Fugl-Meyer Assessment - Upper Extremity. The FMA-UE is a stroke-specific, impairment-based subscale of the Fugl-Meyer Assessment that evaluates motor function of the upper extremity, including reflex activity, voluntary movement within and out of synergy patterns, coordination, and speed. It is widely used to quantify motor recovery following stroke. Score range: 0 to 66. Direction: Higher scores indicate less motor impairment (better upper limb function). Summary description: |
| Upper-limb motor function - Motor Assessment Scale (MAS) | Pre- and post-intervention (4 weeks) | Motor Assessment Scale - Upper Limb Items. This subset of the Motor Assessment Scale includes the upper limb-related items (upper arm function, hand movements, and advanced hand activities). Each item is scored from 0 to 6, providing a focused assessment of functional motor performance of the upper limb in individuals post-stroke. Score range: 0 to 18. Direction: Higher scores indicate better upper limb motor function |
| Handgrip strength | Pre- and post-intervention (4 weeks) | Measured using a Baseline® Hydraulic Hand Dynamometer; three trials per hand averaged. |
| Global disability - modified Rankin Scale (mRS) | Pre- and post-intervention (4 weeks) | The Modified Rankin Scale (mRS) is a clinician-reported outcome measure of global disability following stroke. It assesses the level of functional independence, ranging from 0 (no symptoms) to 6 (death), and is widely used in clinical trials to evaluate overall outcome and disability. Score range: 0 to 6. Direction: Higher scores indicate greater disability (worse outcome) |
Outcome results
None listed