Application of a single-flicker online SSVEP BCI for spatial navigation

Area of Science:

• Neuroscience
• Biomedical Engineering
• Human-Computer Interaction

Background:

• Steady-state visual evoked potential (SSVEP) based brain-computer interfaces (BCIs) offer high information transfer rates (ITR) and simple setups.
• Traditional SSVEP BCIs necessitate direct gaze at stimuli, potentially causing user fatigue and photic epileptic seizures.
• A need exists for SSVEP BCI paradigms that mitigate these drawbacks while maintaining performance.

Purpose of the Study:

• To introduce and evaluate a novel spatially coded SSVEP BCI paradigm.
• To assess the feasibility of using a single, extrafoveally presented stimulus for multi-channel control.
• To integrate this paradigm into an online BCI for a 2D computer game and analyze its performance.

Main Methods:

• Development of a spatially coded SSVEP stimulation paradigm using a single, extrafoveal flicker stimulus.
• Implementation of the paradigm within an online BCI for navigating a 2D computer game.
• Offline and online performance evaluation, including classification accuracy and information transfer rate (ITR).

Main Results:

• Offline analysis demonstrated high classification accuracy (96.9±1.64%) and ITR (30.1±1.8 bits/min).
• Online testing achieved a classification accuracy of 87.9±11.4% and an ITR of 23.8±6.75 bits/min.
• Stable online performance was maintained for over 30 minutes, indicating reliable control.

Conclusions:

• The spatially coded SSVEP BCI effectively enables control using peripheral vision, addressing limitations of traditional methods.
• The novel paradigm is suitable for practical applications like gaming, offering robust and stable user control.
• Further research may explore the relationship between offline and online performance for personalized BCI calibration.