Measurement of mental stress using CNV and salivary IgA

The focus was on establishing standards for the measuring and evaluation of contingent negative variations (CNV) on mental stress. The relationship between CNV and salivary IgA was especially studied. Subjects experimentally performed a word processing task for 2 h. In their pre- and posttask, CNV and salivary IgA were measured and evaluated. In a reference experiment, a reading task was done. A negative area of CNV wave form was introduced. In the word processing task, the negative area of unskilled subjects in the after task was smaller than for the premeasurement. Results of salivary IgA indicated that unskilled subjects' IgA increased. From these results, it was shown that the variations in the negative area of the CNV was a useful measure of mental stress.