Conditional Entropy: A Potential Digital Marker for Stress.

Soheil Keshmiri

doi:10.3390/e23030286

Abstract

Recent decades have witnessed a substantial progress in the utilization of brain activity for the identification of stress digital markers. In particular, the success of entropic measures for this purpose is very appealing, considering (1) their suitability for capturing both linear and non-linear characteristics of brain activity recordings and (2) their direct association with the brain signal variability. These findings rely on external stimuli to induce the brain stress response. On the other hand, research suggests that the use of different types of experimentally induced psychological and physical stressors could potentially yield differential impacts on the brain response to stress and therefore should be dissociated from more general patterns. The present study takes a step toward addressing this issue by introducing conditional entropy (CE) as a potential electroencephalography (EEG)-based resting-state digital marker of stress. For this purpose, we use the resting-state multi-channel EEG recordings of 20 individuals whose responses to stress-related questionnaires show significantly higher and lower level of stress. Through the application of representational similarity analysis (RSA) and K-nearest-neighbor (KNN) classification, we verify the potential that the use of CE can offer to the solution concept of finding an effective digital marker for stress.

Highlights

Stress depletes our capacity for reasoning [1,2,3] via strengthening the memories of stressful experiences [4,5,6] and reinforcing the state of fearful arousal that urges the need for rapid defense mechanisms [7,8,9]
We show that conditional entropy (CE) highlights the effect of stress on the brain’s frontoparietal network [64], which plays a pivotal role in self-referential processing [65], emotion [66], and social cognition [67]
The present study took a preliminary step toward the identification of an EEG-based resting-state digital marker for stress

Summary

Introduction

Stress depletes our capacity for reasoning [1,2,3] via strengthening the memories of stressful experiences [4,5,6] and reinforcing the state of fearful arousal that urges the need for rapid defense mechanisms [7,8,9]. Jacobson and colleagues [25] utilized actigraphy data from healthy individuals on the one hand and patients with major depressive and bipolar disorders on the other hand to report a high prediction accuracy (89.0%) on patients’ status. Their results suggested that actigraphy data may establish reliable measures for predicting changes in patients’ symptoms across a two-week period

Methods

Results

Conclusion