ELECTROCARDIOGRAPH

PROBLEM TO BE SOLVED: To detect that a part of the body of a subject is in contact with each of induction electrodes, in an electrocardiograph.SOLUTION: This electrocardiograph 1 generating the electrocardiographic waveform of the subject Hm includes: the induction electrodes ER, EL; a detection signal input system 40 inputting detection signals SDr, SDl each having a frequency higher than the frequency of a signal detected from the subject Hm as the electrocardiographic waveform, each having a potential higher than an assumed potential, and having the potentials different from each other to the induction electrodes ER, EL; a differential amplifier 10 deriving a differential signal Sd representing a difference between signals Sr, Sl input through the respective induction electrodes ER, EL; and a grip detection circuit 20 generating a grip signal Sg representing the grip state of a steering wheel SW based on the differential signal Sd. In the electrocardiograph 1, the potential of the differential signal Sd varies according to the contact state (that is, the grip state of the steering wheel SW) of the body of the subject Hm to the induction electrodes ER, EL.