EEG Negativity in Fixations Used for Gaze-Based Control: Toward Converting Intentions into Actions with an...

Area of Science:

• Neuroscience
• Human-Computer Interaction
• Biomedical Engineering

Background:

• Eye movements are crucial for human-machine interaction, but differentiating intentional from spontaneous gaze is challenging.
• Effective interfaces require distinguishing deliberate actions from visual exploration to avoid errors.
• Electroencephalography (EEG) offers a potential method for decoding brain activity related to eye movements.

Purpose of the Study:

• To identify an EEG marker that differentiates intentional gaze fixations used for control from spontaneous fixations during visual exploration.
• To assess the feasibility of using EEG-based fixation-related potentials (FRPs) for controlling a human-machine interface.
• To lay the groundwork for a hybrid dwell-based Eye-Brain-Computer Interface (EBCI).

Main Methods:

• Collected gaze-synchronized EEG data from eight healthy participants playing a game using only eye movements.
• Recorded EEG during control-on and control-off conditions to capture intentional and spontaneous fixations, respectively.
• Analyzed fixation-related potentials (FRPs) using amplitude features from 13 EEG channels, focusing on segments free from electrooculogram contamination.

Main Results:

• A distinct slow negative wave in parietooccipital EEG activity was observed during intentional fixations (control-on) but not during spontaneous fixations (control-off).
• Classification algorithms achieved a specificity of 0.90 ± 0.07 for differentiating intentional from spontaneous fixations.
• Sensitivity for classifying the first intentional fixations was 0.38 ± 0.14, with lower rates for subsequent fixations.

Conclusions:

• An EEG marker reliably differentiates intentional from spontaneous eye fixations, enabling control signals.
• The identified FRP difference holds promise for developing a hybrid dwell-based EBCI.
• This technology could lead to the "Wish Mouse," a novel input device for both paralyzed and healthy users, improving interaction fluency.