Glottal Waveform Analysis of Physical Task Stress Speech

Physical task stress affects the acoustic speech wave in various ways. Motivated by observations that fundamental frequency and open quotient are affected by physical task stress, this study examines the effects of physical task stress on a set of glottal features. It is shown that a set of six glottal features can be used for physical stress detection, implying that physical task stress affects vocal fold behavior. It is also shown that the distributions of these six glottal features, across all available speech data, are not affected by physical task stress, leading to the conclusion that covariation in the features due to physical task stress represents different behavioral responses to physical stress. Age and exertion level are explored and rejected as explanatory variables for behavioral types. It is shown, however, that the glottal measurements show changes in distribution when restricted to one recording session of one speaker, suggesting that a given speaker may adopt and retain a particular response to physical task stress for the duration of a task.