arXiv subjects

Ofir Chibotero

Publications and source records attributed to Ofir Chibotero.

3 recordsLinked to original sources

arXiv2025

Personalized Detection of Stress via hdrEEG: Linking Neuro-markers to Cortisol, HRV, and Self-Report

Chronic stress is a risk factor for cognitive decline and illness, yet reliable individual markers remain limited. We tested whether two single channel high dynamic range EEG biomarkers, ST4 and T2, index stress responses by linking neural activity to validated physiological and subjective measures. Study 1 included 101 adults between 22 and 82 years of age who completed questionnaires on stress, resilience, and burnout, provided salivary cortisol, and performed resting, cognitive load, emotional, and startle conditions. Study 2 included 82 adults between 19 and 42 years who completed the State Trait Anxiety Inventory, underwent heart rate variability monitoring, and performed auditory, stress inducing, and emotional conditions. Correlations were considered meaningful when r was at least 0.30. Results showed that ST4 reflected physiological arousal and cognitive strain. In Study 1, resting ST4 was positively related to cortisol and lower in more resilient participants. In Study 2, ST4 correlated negatively with heart rate variability during stress and recovery. T2 reflected emotional and autonomic regulation. In Study 1, T2 tracked higher cortisol and was lower with greater resilience. In Study 2, T2 was higher with trait anxiety and correlated negatively with heart rate variability during stress and emotional conditions. Together, ST4 and T2 provide complementary portable markers of stress, supporting individualized assessment in clinical and real world contexts.

q-bio.NC↗

arXiv2025

Dissociating Cognitive Load and Stress Responses Using Single-Channel EEG: Behavioral and Neural Correlates of Anxiety Across Cognitive States

Identifying neural markers of stress and cognitive load is key to developing scalable tools for mental state assessment. This study evaluated whether a single-channel high-density EEG (hdrEEG) system could dissociate cognitive and stress-related activity during a brief auditory task-based protocol. Sixty-eight healthy adults completed resting state recordings, cognitively demanding auditory tasks, and exposure to unpredictable literalized startle stimuli. Participants also rated their stress and anxiety using a modified State-Trait Anxiety Inventory (STAI). EEG analysis focused on frequency bands (Theta, Gamma, Delta) and machine-learning-derived features (A0, ST4, VC9, T2). A double dissociation emerged: Theta and VC9 increased under cognitive load but not startle, supporting their sensitivity to executive function. In contrast, Gamma and A0 were elevated by the startle stimulus, consistent with stress reactivity. ST4 tracked cognitive effort and worry, while T2 negatively correlated with self-reported calmness, indicating relevance to emotional regulation. These results demonstrate that a short, uniform assessment using portable EEG can yield multiple reliable biomarkers of cognitive and affective states. The findings have implications for clinical, occupational, and educational settings, and may inform future neurofeedback protocols targeting simultaneous regulation of attention and stress.

q-bio.NC↗

arXiv2025

The Evaluation of Breathing 5:5 effect on resilience, stress and balance center measured by Single-Channel EEG

Slow-paced breathing is a promising intervention for reducing anxiety and enhancing emotional regulation through its effects on autonomic and central nervous system function. This study examined the neurophysiological and subjective effects of a 5:5 breathing protocol on stress-related EEG biomarkers using a mobile single-channel EEG system. Thirty-eight healthy adults were randomly assigned to either an intervention group (n = 20), which completed two sessions spaced two weeks apart with daily breathing practice, or a control group (n = 18), which completed one session. In each session, participants underwent an auditory EEG assessment with resting, mental load, and startle conditions. The intervention group also completed a guided breathing session during the first visit and practiced the technique between sessions. EEG biomarkers (ST4, Alpha, Delta, Gamma, VC0) and subjective anxiety levels (STAI) were assessed before and after the intervention. A significant reduction in Gamma power was observed in the intervention group immediately following the first breathing session during mental load (p = .002), indicating acute stress reduction. Across sessions, long-term breathing practice led to increased Alpha and Delta power and reduced ST4 activity, suggesting cumulative improvements in emotional regulation and cognitive efficiency. Correlational analyses revealed that changes in VC0 and Alpha were significantly associated with subjective reports of tension, focus difficulty, and calmness. Guided slow-paced breathing at a 5:5 rhythm produces both immediate and sustained effects on neural markers of stress and cognition, with corresponding improvements in subjective anxiety. These findings support EEG-based monitoring as a scalable method for evaluating breath-based interventions and promoting real-time emotional self-regulation.

q-bio.NC↗