A method of sound expression for bioelectric potential changes in plant

A sound expression methodology for AC components of bioelectric potential and a conversion system in real-time manner has been proposed in order to express spatial and temporal diversity in the potential changes on the leaf surface. The system consists of measurement subsystem of bioelectric potential including disk electrodes and amplifiers of thirty two channels, a computer of thirty two bits CPU, digital sound sources based on MIDI standard, thirty two speakers and a modem. In the system, three techniques for bioelectric data conversion have been essentially employed, namely, Pitch Modulation (P.M.) for converting the potential change to frequency of audible sound, Amplitude Modulation (A.M.) for the intensity to sound amplitude, and Threshold Triggering (T.T.) for triggering one-shot sound in excess of threshold level. Throughout an evaluation study of the system, the combination of P.M. and A.M. has made the adaptation to various wave forms in the bioelectric potential changes possible and its effective performance has been confirmed by the simultaneous processing of bioelectric wave forms from different leaves.