Comparative Study On Nonlinear Characteristics Of Music Signals And EEG Signals

Music is an art that reflects the emotions of human life and is an important tool for expressing moods,regulating emotions,and improving physical and mental health in people's daily lives.The emotional resonance of music is a very complicated process that is difficult to mathematically and quantitatively analyze.It involves a large number of interdisciplinary knowledge such as physics,physiology and neuroscience.When the auditory system receives music stimulation and transmits it to the brain,it will short-term increase the excitability of a part of specific nerve cells,thus affecting emotional expression.This process will inevitably affect the body's secretion,and promote the body to produce some hormones or enzymes.In theory,if the stimulation is stimulated by using music with specific characteristics,and the human body that receives the music stimulation produces some beneficial hormones or enzymes,it can achieve beneficial effects such as strengthening the body's metabolism and enhancing immunity.Even in certain occasions,some specific music can influence people's thinking and judgment,and help people better cope with what is happening.EEG is the most important life signal of the human body.It contains a very rich life information of human beings.Many diseases(such as epilepsy)use EEG signals as the basis for diagnosis.The music signal is a kind of physical vibration wave,and the EEG signal is a kind of chemical wave.Both of them are nonlinear signals closely related to people,and can be regarded as a nonlinear dynamic system.Therefore,we can start from the perspective of nonlinear chaos,avoid the limitations of traditional analysis methods,and discuss its nonlinear characteristics and potential connections.Firstly the experiment selected three types of emotional music that can be generally recognized,including joy emotional music,calm emotional music,sad emotional music,and EEG data in SEED EEG datasets that are stimulated by different films to cause joy,calm,and sadness.Secondly,the Kaiser window high-pass filter is used to denoise the music signal and segment the music according to the framing principle.Each segment has 10 s of signal data.Similarly using an independent component analysis method to remove ocular artifact from EEG data and decomposing it into data for 10s each segment.Then use the MATLAB algorithm improved according to the principle of G.P.algorithm to calculate and analyze the correlation dimension of music signal and EEG signal.And use the MATLAB algorithm program improved according to the principle of Wolf method to calculate and analyze the Lyapunov index value of music signal and EEG signal.Finally,the nonlinear indicators of EEG signals and music signals are compared and analyzed in different emotion groups.The experimental results are shown below.Piano music expressing three emotions and EEG with three moods respectively have higher correlation dimension and positive Lyapunov index,indicating that piano music and EEG are both nonlinear systems with complex internal structures,and weak chaos.The correlation dimension and the Lyapunov index value of the piano music expressing joy and sadness are more than the piano music that expresses the calm emotion,which indicates the joy and sadness of the piano music is higher than the calm emotional piano music from the complexity of the composition and the difficulty of playing the rhythm,with more complex internal nonlinear structure and stronger chaos.The correlation dimension and the Lyapunov index value of EEG signals with joy and sadness are more than the amplitude and irregularity of time fluctuations in EEG signals under calm emotional state,which indicates the joy or sadness caused by single-factor stimulation will awaken other physiological factors to join this control process,making its nonlinear structure more complicated and chaotic.The correlation dimension of EEG signals is generally higher than that of music signals,which proves that EEG has higher time dimension and spatial dimension than music.The Lyapunov index of music signals is generally higher than that of EEG signals,which means that music is the result of human brain thinking and playing according to music scores,each process carries a lot of certainty and uncertainty,small differences will cause more changes,and the degree of nonlinear chaos is higher than that of human brain.