Evaluation of acoustic correlates of speech under stress for robust speech recognition

Results are presented of an investigation of how speech characteristics change under varying levels of stress with specific application to improving automatic isolated-word speech recognition. The evaluation focused on five speech analysis domains: pitch, glottal source, intensity, duration, and vocal tract shaping. Goodness-of-fit statistical tests were used to ascertain the significance of parameter variation in each domain. Results from analysis of pitch and glottal source spectrum are presented. The findings suggest that such parameter information can be used reliably to aid in automatic isolated-word speech recognition in noisy stressful environments