Abstract
Abstract Due to inappropriate work design or lack of consideration for employee workload, the increased mental load is likely to induce mental work stress, which relates much to modern diseases. Therefore it is not hard to discover the graveness of mental work stress. In order to effectively prevent mental work stress from elevating beyond acceptance, it is a must to measure mental work stress. Previous studies have shown the β2 amplitude of occipital midline as a useful index, and thus will be the focus of this research. There were forty subjects, separated into four groups mainly according to age (20-29 year and 30-39 year) and sex, and then randomly selected ten subjects from each group whose body health conditions meet the demands of this experiment. The experiment design was conducted with five-factor experiments with repeated measures on three factors, the two factors being age and sex, and the other three factors being work, area and difficulty. The mental work stress induced by the experiment was measured with subjective and objective measures. The results showed that the occipital area of the left and right brain have their β2 amplitude increased as work difficulty rises, that of female subjects higher than in men, but there was no difference during resting time. Though different under various conditions, the mental load is similar doing different work when measured subjectively. So the β2 amplitude is a useful index for estimating human work stress caused by various mental tasks. Other indices (such as heart rate and blood pressure) did not rise obviously despite the escalation going along with work difficulty; therefore it is less appropriate to use it to measure mental work stress.