Clinical application of micro-vibration to autonomic function test

Microvibration (MV) is the minute vibration observed on surface of the human body. MV on the thenar eminence has been used as an autonomic function test, and is one of the important psychophysiological methods in psychosomatic medicine because the measurement of MV is not invasive. Although the mechanism generating MV has not been definitely clarified, there seems to be two major components, a ballistocardiographic one and a muscular one. The analysis of MV focuses on frequency characteristics. To broaden the clinical application of MV measurement, it is necessary to improve the analyzing method and to develop a way for evaluating MV comprehensively by combining it with other examinations.