Does feedback based on FES-evoked nociceptive withdrawal reflex condition event-related desynchronization? An...

Area of Science:

• Neuroscience
• Rehabilitation Engineering
• Biomedical Engineering

Background:

• Event-related desynchronization (ERD) is crucial for brain-computer interfaces (BCI) to detect motor intention (MI).
• Functional electrical stimulation (FES)-evoked nociceptive withdrawal reflex (NWR) is explored for lower limb synergistic movement and gait rehabilitation in stroke patients.
• The impact of NWR as a sensorimotor feedback on MI detection in ERD-based BCIs remains uninvestigated.

Purpose of the Study:

• To assess electroencephalography (EEG) event-related desynchronization (ERD) during motor intention (MI) after FES-evoked nociceptive withdrawal reflex (NWR).
• To determine if nociceptive stimuli condition subsequent ERDs in an ERD-based BCI.

Main Methods:

• EEG data from 528 trials across 8 healthy volunteers were analyzed.
• Participants used an ERD-based BCI with intrinsic (FES-evoked NWR) and extrinsic (virtual reality) feedback.
• Key outcome measures included normalized root mean square of evoked electromyogram (RMS), average EEG amplitude during MI (A¯MI), and ERD percentage decrease (ERD%).

Main Results:

• No significant changes in RMS, A¯MI, or ERD% were detected for subsequent motor intentions (p > 0.252).
• A significant effect of feedback type was observed for subsequent A¯MI (p < 0.001), with intrinsic feedback yielding higher values.
• No evidence of ERD conditioning was found with FES-evoked NWR feedback.

Conclusions:

• FES-evoked NWR does not appear to condition ERD in BCI-based motor intention detection.
• NWR feedback shows potential as a viable sensory modality for ERD-based BCIs.
• This modality could aid motor recovery in stroke individuals by enhancing BCI performance.