Sample Entropy Analysis of Sleep EEG under Different Stages

First, sample entropy characteristic analysis applied to a mixture system which stochastic signal and determinate signal included is discussed. The result shows that the sample entropy can reflect the complexity of the mixture system accurately. And then, the experiment data in different sleep stages were analyzed using sample entropy as a characteristic value of sleep EEG. It is clearly that the sample entropy of different sleep stages are difference, the deeper the sleep the smaller the sample entropy. Therefore, sample entropy can be a nonlinearity characteristic parameter in sleep automatic stage.