An electrogastrogram (EGG) is a recording of the electric activity of the stomach as measured on the abdominal surface. In this study, our goal is to obtain a mathematical model of an EGG obtained for a subject in the supine position. Initially, we applied the translation error in the Wayland algorithm to the EGG in order to measure the degree of determinism. However, we could not determine whether or not the mathematical model of the EGG could be defined on the basis of a chaotic process. The waveform of the electric potential in the interstitial cells of Cajal is similar to the graphs of the numerical solutions to the Van der Pol equation (VPE). We therefore added the VPE to a periodic function and random white noise was used to represent the intestinal motility and other biosignals, respectively. The EGG and numerical solutions were compared and evaluated on the basis of the translation error and the maximum Lyapunov exponent. The EGG was well described by the stochastic resonance in the stochastic differential equations.
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