An alpha wave signal and a beta wave signal are separated from a brain wave signal S at the points of the subject's forehead, and under the condition of preset time of a sampling cycle with a settled integration time, a ratio of an integration value of the beta wave signal to an integration value of the alpha wave signal is calculated to obtain the information for judgment of the brain activity. Under the condition of preset time of the sampling cycle with a settled integration time, each integration value of brain wave signal S, said alpha wave signal and said beta wave signal are calculated, then an occurrence ratio of the integration value of the alpha wave signal to the integration value of the brain signal S is calculated and made to be alpha% for each sampling cycle, beta% is calculated by the same procedure, and the frequency distribution curve of the alpha% and beta% is calculated to obtain the information for judgment of the brain activity. The ratio of beta% to alpha% is calculated for each sampling cycle, then the average values and the frequency distribution curve of the ratio value of beta% to alpha% in a sampling period is calculated to obtain the information for the judgment of the brain activity. According to these results of the information described above, the mind disorder is correctly judged and also the fault of the questionnaire judgment can be compensated.
Judgment method of the brain wave activity and the brain wave activity quantification measurement equipment