Voice Signatures of Momentary Psychological Stress in Real-Life Environments: Results from the Colive Voice Study

Voice is hypothesized to be modulated by stress and thus could be used as a potential stress detection and monitoring solution. In the literature, vocal biomarkers for stress have mostly been developed on experimental data, with limited samples. Therefore, this study aimed to present insights into the effect of momentary psychological stress on voice in real-life recordings, across different languages, genders, and vocal tasks.

Participants from the Colive Voice study reported their stress level on a 1 to 5 Likert scale. Two tasks were performed: a text reading task and an A-vowel phonation. We analyzed the data cross-sectionally. We extracted vocal features with the DisVoice library and performed ordinary least squares regression models to evaluate the association of vocal features with stress. Models were stratified by gender and language (French/English) and controlled for age, smoking status, alcohol consumption, the presence of chronic disease, education level, mother tongue, well-being, fatigue, and depression. Benjamini-Hochberg correction was applied to control for multiple testing.

We analyzed a sample of 4,155 participants, 2,011 in French (1,621 women, 390 men) and 2,144 in English (1,105 women, 1,039 men). In the text reading task, we found that stress was associated with two articulatory features for English-speaking women. Among French-speaking women, higher stress was linked with lower pitch and higher shimmer. The duration of pauses and one glottal feature were also associated with stress. In the A-vowel phonation task, pitch and the variability of the pitch perturbation quotient were lower with stress in English-speaking men. French-speaking women had increased voice intensity and loudness with stress.

We were able to confirm the association of momentary psychological stress with various vocal features in real-life settings, but not across languages, vocal tasks, or gender. Future research should include longitudinal studies to investigate the potential of using voice as an intraindividual monitoring biomarker for stress.