Acupuncture Characterization Based On The Electrical Signal

Acupuncture is a systemic science; thus to study its function and mechanism provides guiding meaning for clinical diagnosis and research. It's an important research part in neuroscience to explore the mechanisms of the neural coding. With the development of chaos theory, it has been applied in numerous areas including biomedical engineering. Meanwhile, the signal time-frequency analysis and information theory are also popular research methods.In this thesis, we design two kinds of experiments. One is acupuncture on Zusanli to obtain action potentials on the spinal dorsal root, the other is acupuncture on Zusanli to obtain action potentials on the spinal dorsal horn.We obtain the interspike-interval (ISIs) of the acupuncture signals evoked by different manipulates, and then use the first return map and probability distribution fit to analyze them. By considering the concept of the point process, correlation analysis in time domain and frequency domain is employed to analyze the spike trains.The nonlinear time series analysis methods are proposed to study four acupuncture electrical signals for the first time. Power spectrum analysis is applied to imply the signals are chaotic. Then phase space reconstruction is applied among which mutual information method to obtain the time delay and Cao's method to obtain the embedding dimension, and stranger attractors are reconstructed. On the basis of the reconstruction, we characterize the attractors in terms of correlation dimensions, largest Lyapunov exponents and Kolmogorov complexity measures. Two additional methods are chosen: recurrence plot to determine the stationarity of the signals and the surrogate data method to estimate the deterministic nonlinearity property of the signal. The weighted zero-order local prediction method is applied to forecast the electrical signals.Last but not the least, by combining the wavelet theory and information theory, fundamental definitions of wavelet entropy measure are discussed. Calculation methods including wavelet energy entropy, wavelet time entropy, wavelet singular entropy, wavelet time frequency entropy are put forward to extract the characteristics of the electrical signals, and their meanings are analyzed.The results of this thesis can give some theoretical supports to the quantification and scientification of the acupuncture.