Disclosed is an system for measuring mood states (60), which calculate and views high-accurate mood indices from brain activation signals obtained by a non-invasive biospectrometric technology, taking account into differences among individuals, for example cognitive capacity using methods supporting the measurement of mood states of individuals. The system of the present invention stores a plurality of different mood index calculation formulae, selects one of the plurality of mood index calculation formulae based on a personal trait, for example the working memory task performance or working memory capacity of a subject, and substitutes the brain activation data of the subject for the selected calculation formula to calculate and view mood indices.
