Entropy-Dominated Temporal Vocal Dynamics as Digital Biomarkers for Depression Detection

arXiv cs.LG / 5/1/2026

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Key Points

  • The study evaluates whether entropy-based temporal voice biomarkers can detect depression more effectively than standard static, pooled conversational features.
  • Using the DAIC-WOZ dataset with 142 labeled participants, the researchers reconstruct utterance-level acoustic trajectories and compare multiple temporal-feature approaches under leakage-aware validation.
  • Static pooling yields an AUC of 0.593, while modeling trajectory dynamics improves it to 0.637, and entropy biomarkers provide the best statistically significant gain with AUC 0.646 (nested AUC 0.615; permutation p = 0.017).
  • Entropy biomarkers outperform alternative temporal measures such as recurrence quantification, coupling biomarkers, sample entropy, and fractal-based features, with several biomarkers showing stability across validation folds.
  • The results suggest depression-relevant information may be captured more by the uncertainty/entropy of conversational dynamics than by average acoustic levels, enabling more temporally informed digital phenotypes for mental-health assessment.

Abstract

Automated depression detection often relies on static aggregation of conversational signals, potentially obscuring clinically meaningful behavioral dynamics. We investigated whether entropy-driven temporal biomarkers improve depression detection beyond standard pooled features using the DAIC-WOZ corpus. Using 142 labeled participants, we reconstructed utterance-level acoustic trajectories and compared pooled temporal baselines, trajectory dynamics, Shannon entropy biomarkers, recurrence quantification, sample entropy, fractal complexity, and coupling biomarkers under leakage-aware validation. Static pooling achieved an AUC of 0.593, trajectory dynamics improved performance to 0.637, and entropy biomarkers produced the strongest statistically significant improvement over pooled baselines (AUC 0.646; nested cross-validated AUC 0.615; permutation p = 0.017). Entropy biomarkers outperformed recurrence, coupling, sample entropy, and fractalbased features, with several biomarkers stable across folds. These findings suggest depression-related signal may lie less in average acoustic levels than in entropy of conversational dynamics, supporting temporally informed digital phenotypes for mental-health assessment.