Voice Stress Analysis

The non-verbal content of speech carries information about the physiological and psychological condition of the speaker. Psychological stress is a pathological element of this condition, of which one of the causes is accepted to be workload. Objective, quantifiable correlates of stress are searched for by means of measuring the acoustic modifications of the voice brought about by workload. Different voice features from the speech signal to be in- fluenced by stress are: loudness, fundamental frequency, jitter, zero-crossing rate, speech rate and high-energy frequency ratio. To examine the effect of workload on speech production an experiment was designed. 108 native speakers of Dutch were recruited to participate in a stress test (Stroop test). The experiment and the analysis of the test results will be reported in this paper.