Title: Acoustic analysis of speech under stress

Authors: Savita Sondhi; Munna Khan; Ritu Vijay; Ashok K. Salhan; Satish Chouhan

Addresses: Department of Electrical, Electronics & Communication Engineering, ITM University, Gurgaon 122017, Haryana, India ' Department of Electrical Engineering, Jamia Millia Islamia (Central University), New Delhi 110025, India ' Department of Electronics, Banasthali University, Banasthali 304022, Rajasthan, India ' Biomedical Instrumentation Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Timarpur, New Delhi 110054, India ' Biomedical Instrumentation Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Timarpur, New Delhi 110054, India

Abstract: When a person is emotionally charged, stress could be discerned in his voice. This paper presents a simplified and a non-invasive approach to detect psycho-physiological stress by monitoring the acoustic modifications during a stressful conversation. Voice database consists of audio clips from eight different popular FM broadcasts wherein the host of the show vexes the subjects who are otherwise unaware of the charade. The audio clips are obtained from real-life stressful conversations (no simulated emotions). Analysis is done using PRAAT software to evaluate mean fundamental frequency (F0) and formant frequencies (F1, F2, F3, F4) both in neutral and stressed state. Results suggest that F0 increases with stress; however, formant frequency decreases with stress. Comparison of Fourier and chirp spectra of short vowel segment shows that for relaxed speech, the two spectra are similar; however, for stressed speech, they differ in the high frequency range due to increased pitch modulation.

Keywords: voice stress analysis; stressed speech; fundamental frequency; formant frequency; FFT; chirp transform; bioinformatics; emotional stress; acoustic analysis; psycho-physiological stress; stressful conversation; pitch modulation.

DOI: 10.1504/IJBRA.2015.071942

International Journal of Bioinformatics Research and Applications, 2015 Vol.11 No.5, pp.417 - 432

Accepted: 18 May 2015
Published online: 24 Sep 2015 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article