PURPOSE: To make it possible to measure the degree of concentration of an examinee correctly, independently of measuring environment and in realtime by measuring the proportion of the power Pα of α wave that suggests the degree of concentration to the total power of brain waves as the degree of concentration.
CONSTITUTION: The detected signals of brains waves from a living body are inputted to a band-pass filter 11 and the signal component of 0.5-30.5Hz is passed. The A/D converter 12 digitizes the signals and sends them to the filtering device 13. The signal components of every 1Hz width of 0.5-30.5Hz are extracted in a filtering device 13, and based on the signal component, an integrating device 14 integrates the spectra of the signal component of α wave of 7.5-13.5Hz, and the power P0 of brain wave is calculated by integrating the spectra of total brain waves of 0.5-30.5Hz, and sent to an arithmetic unit 15 together with the power Pα of α wave described above. The arithmetic device 15 calculates the proportion of the power of α wave Pα to the total power of brain waves P0, and displays the degree of concentration on the displaying device 17.
SATO TOSHIYUKI
TAKIGAWA MORIKUNI
KAWASAKI HIROTOKI
