SSVEP-Aided Recognition of Internally and Externally Directed Attention from Brain Activity

Steady-state visually evoked potentials (SSVEP) are a widely used paradigm for the detection of attended objects. However, their aid in the recognition of other attentional states has not yet been studied in detail. In this study (n=21), we assessed the benefits of including SSVEP stimuli as probes...

Full description

Saved in:
Bibliographic Details
Main Authors: Vortmann, Lisa-Marie, Klaff, Jonas, Urban, Timo, Putze, Felix
Format: Conference Proceeding
Language:English
Subjects:
Brain
Correlation
Electrodes
Electroencephalography
Linear discriminant analysis
Steady-state
Task analysis
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Steady-state visually evoked potentials (SSVEP) are a widely used paradigm for the detection of attended objects. However, their aid in the recognition of other attentional states has not yet been studied in detail. In this study (n=21), we assessed the benefits of including SSVEP stimuli as probes in a screen-based task to classify internal and external attention based on 16-channel EEG data offline. Previous studies have shown that the distinction between these two attentional states based on brain activity is possible. We compared several SSVEP-stimulus settings with a baseline where no SSVEP stimulus was present. Different flickering frequencies and stimulus placements were evaluated for the possibilities of different experimental setups. We found that the influence of the stimulus on the classification accuracy is highly dependent on the settings. The Linear Discriminant Analysis (LDA) performance increased significantly when an SSVEP-evoking stimulus with a low flickering frequency was present in the center of fixation. As well as when a Canonical Correlation Analysis (CCA)-coefficient was added as the SSVEP-specific feature to a generic band-power feature set. A simple training-free, person-independent threshold approach for internal and external attention detection resulted in accuracies significantly higher than chance based on SSVEP-features that were calculated only on three occipital electrodes. These results show that such stimuli can aid the recognition of internal and external attention. Thus, they can be used in experiments or applications for a more robust detection rate. Specifically, they could improve SSVEP-based BCI paradigms by adding another level of attention-awareness.
ISSN:2577-1655
DOI:10.1109/SMC52423.2021.9659098