BCI With Virtual Reality for Stroke Rehabilitation: A Crossover Study

Brain-Computer Interface (BCI) With Virtual Reality (VR) in Upper Limb Rehabilitation After Stroke: A Randomized Crossover Clinical Trial

The goal of this clinical trial is to investigate if training sessions of motor imagery associated with brain-computer interface and motor observation through virtual reality (MI-VR-BCI) can help to improve arm and hand recovery after a stroke. The main questions to answer are:

• Can adding MI-BCI-VR sessions improve upper limb movement?
• Can it help stroke survivors perform daily activities more easily?
• Does this type of training improve brain activity and connections related to movement?

Researchers will compare this type of intervention with motor imagery associated with a standard brain-computer interface intervention (MI-BCI) to see if there are added effects to upper limb function, activity and brain connections.

Participants will :

• Perform two intervention periods in a random order: one with MI-VR-BCI training sessions and other with MI-BCI training sessions. Each period will involve 3 weekly sessions of training, during 6 weeks, with the intervention periods being separated by 3 weeks.
• Complete four assessment sessions: one at the beginning and another at the end of each intervention period.

Stroke is a leading cause of long-term disability worldwide, often resulting in upper limb (UL) impairment. Approximately 70% of stroke survivors experience UL dysfunction, with a significant portion continuing to show deficits into the chronic phase. This impacts independence and quality of life, highlighting the need for effective rehabilitation strategies.

Brain-Computer Interface (BCI) interventions have shown promise in improving UL function by enabling patients to modulate brain activity through neurofeedback in a closed-loop system. When combined with multisensory feedback (visual, auditory, and somatosensory) BCIs may promote neuroplasticity and motor recovery. The use of Motor Imagery (MI) and embodied Virtual Reality (VR) may further enhance motor learning by reinforcing motor patterns and creating meaningful, immersive rehabilitation experiences.

Despite encouraging evidence, the clinical and neurophysiological benefits of combining BCI with VR and MI remain underexplored, particularly when associated with longer intervention periods, the impact in activities of daily living and the influence of patient-specific traits such as motor, cognitive, or behavioral dimensions. In light of these considerations, the primary objectives of this study are:

• To assess the preliminary effects of applying a motor imagery based Brain-Computer Interface with Virtual Reality (MI-BCI-VR) paradigm on upper limb function and activity in individuals with stroke.
• To evaluate the neurophysiological effects of this intervention on brain activity and its relationship with clinical measures of upper limb function.

The secondary objectives of the study are:

• To explore the influence of individual characteristics on clinical outcomes and neurophysiological changes observed.
• To examine the specific contribution of embodied Virtual Reality associated with BCI in upper limb rehabilitation after stroke.
• To understand participant's experience with the different intervention paradigms, including acceptability and usability, and to inform the technology development process.

Inclusion Criteria:

• Clinical diagnosis of stroke confirmed by neuroimaging, with resulting upper limb hemiparesis.
• Time since stroke between 6 and 24 months at the time of selection.
• Sufficient cognitive ability to understand and follow the intervention procedures.
• Spasticity score <3 on the Modified Ashworth Scale in upper limb muscle groups.
• Adults aged 18 to 80 years.
• Ability to remain seated for approximately 2 hours.
• Motivation to participate and capacity to provide informed consent.
• Undergoing conventional rehabilitation therapy during the study period.

Exclusion Criteria:

• Severe communication difficulties preventing comprehension or execution of instructions.
• Skin lesions, allergies, or metal implants in the cephalic region, or history of craniectomy, that hinder electrode placement or interfere with EEG signal acquisition.
• Concomitant neurological or musculoskeletal conditions affecting upper limb motor function.
• Other neurological, musculoskeletal, or psychiatric conditions that may compromise participation or study outcomes (e.g., major depression, severe visual impairment, photosensitive epilepsy, frequent vertigo or dizziness).
• Upper limb impairment due to a previous stroke.