The Study Of Propagation Characteristics Of Low Frequency Oscillation Signal Measured In The Periphery Sites Of Human On Task-state

The low frequency oscillation signal(0.01~0.15Hz)is a spontaneous slow change signal of hemodynamic parameters.Its physiological origin has not been fully understood yet.In general,the signal reflects the neural process in the reflex,the systemic blood power and the auto regulation of the brain blood vessels,which can be used as a biomarker in the blood circulation and reflect the physiological information of blood vessels.In some medical institutions,as a noninvasive and inexpensive functional measurement method with high time resolution,near infrared spectroscopy can be used to collect low frequency oscillating signals in blood vessels.However,the physiological information reflected in the resting state is relatively limited.Therefore,we ultilize the developed multi-channel near infrared oximeter to collect the data of low frequency oscillation on task-state.On the basis of the data analysis,we explore how the low frequency oscillation signals spread in the vascular peripheral sites on different task-states and explore the hidden physiological information,which is of great significance in clinical diagnosis and treatment..Firstly,in order to collect the low frequency oscillating signal in the human body,we propose a series of simple experiment,including passively rasing leg test and paced breathing test.On the basis of data preprocessing,a complete stategy of signal processing was proposed for data analysis,which consist wavelet time-frequency method,phase locking synchronization method,correlation coefficient method and so on.And these methods have been proved on resting state.Secondly,on the basis of the analysis of the mechanism of cardiovascular regulation caused by passive leg raising,the propagation characteristics and laws of low frequency oscillation signals caused by local passive leg raising are explored.Using the wavelet timefrequency method,the change of signal in varites of frequency with time over time is analyzed,and time domain and frequency domain correlation analysis method is used to calculate the delay of the arrival time signal to every peripheral site.Lastly,on the basis of the analysis of the mechanism of cardiovascular regulation caused by paced breathing,the propagation characteristics and laws of low frequency oscillations caused by paced breathing are explored.We use the time frequency analysis method and combine the result of passively leg raising research to statictic the propagation of the signal caused by task in every peripheral site.By using the less error lock phase synchronization method,the phase locking value of low frequency oscillation signal in different sites were calculated.