Voice analysis to predict the psychological or physical state of a speaker

Abstract

A vocal message, apart from its semantic content, carries information on the psychological and physiological condition of the speaker. Physical fatique and especially psychological stress are the pathological elements of the condition. The accepted term for the cause of these effects is the 'workload'. This article describes the main research carried out since the 1940's to measure the acoustic modifications of the voice brought about by a workload. It concludes by a critical analysis of the studies and a short descriotion of the perspectives for research. Their results mainly concern astronauts and pilots involved in specific highstress tasks and possible users of voice recognition systems. All the studies show an excellent apprach to this field of research but deserve to be widened, deepened, and made more accurate to enable estimating the nature or level of reaction to a workload.