Design and Experimental Investigation of a Multi-Level Heartbeat Sound Feedback-Based Neurofeedback System: Neural...

Area of Science:

• Neuroscience
• Cognitive Science
• Human-Computer Interaction

Background:

• Auditory neurofeedback training (NFT) integrated with brain-computer interfaces (BCIs) is a novel paradigm for regulating neural states during motor tasks.
• Task-embedded NFT differs from standalone approaches by incorporating feedback directly into task execution, creating a dual-task scenario.
• The impact of this dual-task scenario on neural activity and behavioral performance in precision motor skills remains under-investigated.

Purpose of the Study:

• To investigate the immediate neural mechanisms and potential dual-task interference effects of single-session auditory NFT in moderately skilled shooters.
• To examine the effects of auditory feedback (SMR enhancement and theta suppression) on EEG features and shooting performance.
• To explore cross-frequency coupling and functional connectivity changes induced by auditory NFT.

Main Methods:

• A closed-loop BCI system with five-level auditory heartbeat sound feedback was developed.
• Twenty-two moderately skilled shooters participated in a within-subject design with no-sound baseline, SMR enhancement, and theta suppression conditions.
• Simultaneous 32-channel EEG and behavioral data were recorded, analyzed using cluster-based permutation tests, cross-frequency coupling, and functional connectivity (dwPLI).

Main Results:

• Theta feedback significantly suppressed frontal 4-7 Hz activity (cluster p = 0.004), while SMR feedback did not yield significant group-level enhancement.
• Theta feedback induced cross-frequency spillover, decreasing sensorimotor SMR power in responders and showing a positive correlation between frontal theta and SMR changes (r = 0.67, p < 0.001).
• Significant theta-band network reorganization was observed (cluster p = 0.034), but shooting performance did not improve, and aiming time increased, suggesting dual-task interference.

Conclusions:

• Single-session auditory NFT can modulate prefrontal networks and induce neural reorganization, but the feedback itself acts as a parallel task.
• The dual-task nature of task-embedded auditory NFT may limit the short-term transfer of neural changes to behavioral improvements in precision motor skills.
• Findings provide insights into the neural mechanisms and dual-task costs of auditory NFT, informing future designs for motor skill training.