Prediction of Deskwork Stress with Visual Display Terminal by Human Immune Substance in Saliva

Recent psychophysiological studies revealed that the human endocrine and immune secretion changes its level sensitively according to participants´ subjective mental stress and relaxation. In this study, one of the major secretory immune substance, secretory Immunoglobulin A (slgA), is assessed to investigate the human secretory response induced by stressful task of deskwork operations with visual display terminal (VDT). Additionally a mathematical model of the slgA changing is proposed. In the experiment, subjects were required to conduct a short period of work operations with VDT repeatedly with intervals. The result of the experiments indicates that the slgA changing clearly reflects the participants´ subjective stress level. Finally, I introduce a blue print of the VDT work stress prediction system constructed via the mathematical model of slgA modulation proposed in this study.