Chapter 1. Research methods

The first chapter presents methods for analyzing nonstationary physiological signals. Among them are 1) the method of continuous wavelet analysis, which allows obtaining the local and integral distribution of the energy of the wavelet spectrum of the signal over frequencies in a certain time interval, as well as providing information on the cross-wavelet spectrum and wavelet coherence of two signals; 2) methods for assessing the multifractality of a signal by searching for the maxima of the wavelet transform modulus maxima and by analyzing fluctuations relative to the trend; 3) the method of recurrent analysis, which allows to identify the quantitative parameters of the evolution of the signal in time, 4) the method of bifurcation analysis, which allows finding the values of the system parameters at which a qualitative change in the solution of the system occurs, for example, a change in the mode of impulse activity of a neuron