Spatial and Behavioral Characterization of Alpha Suppression and Broadband EEG Activity in Visual Attention

Paying attention to relevant parts of the visual world while ignoring distractions is essential for effective perception and decision-making. Electroencephalography (EEG) has revealed two neural signatures of attention: suppression of alpha-band rhythms and increases in broadband, non-oscillatory activity. While alpha suppression has been well studied, the functional role and behavioral relevance of broadband signals are still unclear—particularly in scalp EEG, where such activity has only recently been reliably observed. This project aims to determine whether these two signals reflect distinct mechanisms of attention and whether either is necessary or sufficient for improving behavioral performance.

The proposed research has two specific aims: (1) compare the spatial patterns of alpha suppression and broadband activity during attention, and (2) test their relationship to behavior by assessing whether either signal predicts improvements in perceptual performance. Participants will perform a visual attention task while EEG is recorded. Frequency tagging will isolate stimulus-specific neural responses, and source localization methods will project EEG data onto the cortical surface. Spatial profiles of neural activity will be quantified and linked to behavioral thresholds across different visual field locations.

By combining frequency-tagged EEG with psychophysics behavioral analysis and source estimation algorithms, this study will clarify how distinct neural signals contribute to attention. The findings will inform both theoretical models of attentional control and potential future applications such as EEG-based neurofeedback and cognitive training.