Mechano-encephalogram based on amorphous wire micro SI acceleration sensor

Time series reflecting human brain activities in mental and emotional state s was detected using a sensitive micro acceleration sensor composed of a Co SiB magnetostrictive amorphous wire connected with a CMOS IC circuit with t he resolution of about 0.1 Gal. A small sensor head of a glass specimen of 0.16 mm thick, 3 mm wide, and 15 nun long on which a CoSiB amorphous wire o f 20 mum diameter and 5 mm long and an inertia mass of 0.1 gr are adhered w as fixed on the center of forehead of a subject. Detected waveforms of the sensor output for several subjects with both eyel ids closed were different from the conventional microvibration and were cla ssified into four kinds representing the states at rest or lightly sleeping , passively stressed, actively stressed, and pleasant imaging. We named the se signals as the mechano-encephalogram separating from the microvibration.