Cognitive Vigilance Enhancement Using Audio Stimulation of Pure Tone at 250 Hz

Fares Al-Shargie,Usman Tariq,Fabio Babiloni,Hasan Al-Nashash

doi:10.1109/access.2021.3054785

Fares Al-Shargie, Usman Tariq + Show 2 more

Open Access

https://doi.org/10.1109/access.2021.3054785

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Abstract

In this paper, we propose a novel vigilance enhancement method based on audio stimulation of pure tone at 250 Hz. We induced two different levels of vigilance state; vigilance decrement (VD) and vigilance enhancement (VE). The VD state was induced by performing a modified version of the Stroop Color-Word Task (SCWT) for approximately 45 minutes. Likewise, the VE state was induced by incorporating audio stimulation of 250 Hz into the SCWT for 45 minutes. We assessed the levels of vigilance on 20 healthy subjects by utilizing Electroencephalogram (EEG) signals and machine learning. The EEG signals were analyzed using four types of entropies; Approximate Entropy (AE), Sample Entropy (SE), Fuzzy Entropy (FE), and Differential Entropy (DE). We then quantified vigilance levels using statistical analysis and support vector machines (SVM) classifier. We found that the proposed VE method has significantly reduced the reaction time (RT) by 44% and improved the accuracy of target detection by 25%, (p <; 0.001) compared to VD state. Besides, we found that 30 min of audio stimulation has reduced the RT by 32% from the beginning to the end of VE phase of the experiment. The entropy measures show that the temporal profile of the EEG signals has significantly increased with VE. The classification results showed that SVM technique with DE features across all frequency bands can detect VE levels with accuracy varying between (92.10± 02.24)% to (98.32± 01.14)%, sensitivity of (92.50± 02.33)% to (98.66± 01.00)%, and specificity of (91.70± 02.32)% to (97.99± 01.05)%. Results also showed that the classification performance using DE has outperformed the other entropy measures by an average of +8.07%. Our results demonstrate the effectiveness of the proposed 250 Hz audio stimulation method in improving vigilance level and suggest using it for future cognitive enhancement studies.

Highlights

Previous studies have highlighted the importance of maintaining high vigilance in multiple applied settings [1]
We examined the changes in subjective feelings of vigilance states with the BRMUS scores and found significant effect of audio stimulation (SCWT vs Stroop Color-Word Task (SCWT)+pure tone (PT)) in concentration
The overall behavioral results indicate that listening to audio stimulation of PT at 250 Hz while performing SCWT for 30 min was effective in eliciting vigilance enhancement to all participants

Summary

Introduction

Previous studies have highlighted the importance of maintaining high vigilance in multiple applied settings [1]. As part of the attentional networks model, is responsible for maintaining the required state of activation to facilitate the functioning of the attentional system, in order to appropriately detect and quickly react to stimuli in the environment [2], [3]. Deterioration in vigilant attention is the primary risk factor for accidents and injury when driving a. A consistent finding reported by several studies is that vigilance affects the user’s reaction time causing a delay or even absence of an appropriate reaction to potentially dangerous events. To avoid the potential of danger and accidents during relatively long demanding cognitive process, vigilance enhancement is required. Vigilance enhancement refers to the deliberate use of technological, medical, or therapeutic interventions to improve cognitive processing and attentional performance [1].

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Discussion

Conclusion