Physical state control system, physical state control method, and oscillatory wave calculation program

Abstract

To provide a physical state control system capable of approximating an automatic nervous system to its normal state while reducing a load applied to a living body, a physical state control method, and an oscillatory wave calculation program.SOLUTION: A physical state control system 1 according to an embodiment comprises: a waveform measurement device for acquiring waveform information on a living body; a physical state control device 50 for calculating an oscillatory wave applied to the living body, based on the waveform information acquired by the waveform measurement device; and a driving device 30 for applying the calculated oscillatory wave from the outside of the living body to at least one of the carotid bifurcation and the vertebral artery of the living body.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a physiological state control system, a physiological state control method, and a vibration wave calculation program.

Background Art

[0002] Patent Document 1 discloses a technique for normalizing the autonomic nervous system by sensing a person's activity and applying appropriate nerve stimulation based on the activity.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Non-Patent Documents

[0004]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the method of Patent Document 1, a nerve stimulation signal is applied by an implantable medical device such as a pacemaker, and the load on the living body such as the device being worn inside the body becomes large.

[0006] The present disclosure has been made to solve such problems, and provides a physiological state control system, a physiological state control method, and a vibration wave calculation program that can bring the autonomic nervous system closer to normal while reducing the load on a living body.

Means for Solving the Problems

[0007] The physiological state control system according to the present embodiment includes a waveform measuring device that acquires waveform information of pulse waves of the carotid bifurcation and vertebral arteries related to a living body and waveforms of each electroencephalogram measured by the 10-20 method or the like, and a physiological state control device that calculates a vibration wave to be applied to the living body based on the waveform information acquired by the waveform measuring device, and a driving device that applies the calculated vibration wave from the outside of the living body to at least one of the carotid bifurcation and vertebral arteries of the living body. With such a configuration, it is possible to reduce the load on the living body and bring the autonomic nervous system closer to normal.

[0008] In order to adjust the activities of the circulatory system, digestive system, respiratory system, etc., the autonomic nervous system works continuously day and night regardless of one's will. Because it is a nerve that reacts automatically, it unconsciously adjusts functions such as respiration, blood circulation, body temperature regulation, digestion, excretion, reproduction, and immunity, and is essential for maintaining life. When the tension of the autonomic nervous system increases, symptoms of autonomic nerve disorder such as body fatigue, constipation or diarrhea, headache, flushing, palpitations, and numbness appear. Controlling these physiological states is considered to be an expression of the function of the brain centered on the brainstem.

[0009] When examining the route of cerebral blood flow that supplies the energy source for brain activity, the blood that has taken in oxygen in the lungs is sent from the left atrium to the left ventricle, and the blood is sent throughout the body from the aortic arch. The left and right common carotid arteries branched from the aortic arch branch into the internal carotid arteries at the carotid bifurcation and supply blood to the frontal lobe, temporal lobe, and parietal lobe. The left and right subclavian arteries branch into the left and right vertebral arteries and supply blood to the brainstem, cerebellum, and occipital lobe along the cervical vertebrae.

[0010] By measuring the waveforms of these sites with the waveform measuring device, information on the blood flow supplied by their arteries can be obtained, and by observing the brain waves of each part of the brain, the activity state of the brain can be observed from both aspects of cerebral blood flow and brain waves.

[0011] In the physiological state control system, the physiological state control device filters the acquired waveform information in at least one frequency band, performs a Hilbert transform on the filtered waveform information in the frequency band, extracts the real part and the imaginary part of the complex wave form obtained by performing the Hilbert transform on the waveform information, takes the real part as the instantaneous amplitude and the imaginary part as the instantaneous phase, calculates the instantaneous frequency which is the time derivative of the instantaneous amplitude and the instantaneous phase during a period that can be regarded as a physiologically steady state, and when calculating the respective distributions, they are distributed in a Gaussian-like manner.

[0012] In the physiological state control system, the physiological state control device may include at least any one of the following frequency bands: 0.004 to 0.015 Hz (VLF2), 0.015 to 0.04 Hz (VLF1), 0.04 to 0.15 Hz (LF), 0.15 to 0.4 Hz (HF), 0.4 to 1.5 Hz (δ1), 1.5 to 4 Hz (δ2), 4 to 8 Hz (θ), 8 to 13 Hz (α), 13 to 30 Hz (β), and 30 to Hz (γ). Also, the δ1, δ2, θ, α, β, γ bands of 1.5 Hz or more may be further divided into a plurality of sections. With such a configuration, the physiological state can be obtained from the brain waves and the pulse waves.

[0013] In the above physiological state control system, when autonomic nerve disorder symptoms appear, it has been observed that the distribution of the amplitude and frequency of at least one of VLF2, VLF1, LF, HF, δ1, δ2, θ, α, β, and γ deviates from the normal distribution in terms of its mean value and variance value. The physiological state control device calculates the instantaneous amplitude and instantaneous frequency such that the mean value and variance value of the amplitude and frequency when the autonomic nerve is abnormal become the distribution of the amplitude and frequency when the autonomic nerve is normal, and by applying those vibrations or pressures to the drive device, it is possible to improve autonomic nerve disorder by bringing the blood flow supplied to the brainstem and the brain closer to the normal value. With such a configuration, the physiological state can be brought closer to normal.

[0014] In the above physiological state control system, the physiological state control device may calculate the vibration wave applied to the living body based on at least any one of electroencephalogram, pulse wave, and pulse interval wave as the waveform information. Also, it may be possible to confirm whether the physiological state is approaching the normal value by checking the distribution shape of the instantaneous amplitude and instantaneous frequency of the electroencephalogram band waveform, and adjusting the amplitude for driving the drive device. With such a configuration, the physiological state can be brought closer to the normal state.

[0015] The physiological state control method according to this embodiment includes a step of acquiring waveform information of at least any one of electroencephalogram and pulse wave related to a living body, a step of calculating a vibration wave applied to the living body based on the acquired waveform information, and a step of applying the calculated vibration wave from the outside of the living body to at least any one of the bifurcation parts of the left and right carotid arteries and the left and right vertebral arteries (left and right cervical vertebrae) of the living body. With such a configuration, it is possible to bring the autonomic nervous system closer to normal while reducing the load on the living body.

[0016] In the above physiological state control method, the step of calculating the vibration wave includes a step of filtering the acquired waveform information in at least one frequency band, a step of performing a Hilbert transform on the waveform information in the filtered frequency band, a step of calculating an instantaneous amplitude corresponding to the real part of the complex wave form obtained by performing a Hilbert transform on the waveform information, an instantaneous frequency corresponding to the time differential value of the instantaneous phase corresponding to the imaginary part of the complex wave form, a step of calculating a Gaussian-like distribution of the instantaneous values, and a step of calculating the vibration wave such that the calculated Gaussian-like distribution becomes the Gaussian-like distribution in a normal physiological state, and has means for storing the distribution shapes of the instantaneous amplitude and instantaneous frequency in a normal physiological state and the distribution shapes of the instantaneous amplitude and instantaneous frequency in a state where the autonomic nerve is abnormal.

[0017] In the above physiological state control method, in the filtering step, as the frequency band, it may include at least any one of the bands of 0.004 to 0.015 Hz (VLF2), 0.015 to 0.04 Hz (VLF1), 0.04 to 0.15 Hz (LF), 0.15 to 0.4 Hz (HF), 0.4 to 1.5 Hz (δ1), 1.5 to 4 Hz (δ2), 4 to 8 Hz (θ), 8 to 13 Hz (α), 13 to 30 Hz (β), and 30 to 100 Hz (γ).

[0018] In the above physiological state control method, based on at least any one of electroencephalogram, pulse wave, and pulse interval waveform as the waveform information, the distributions of the instantaneous amplitude and instantaneous frequency in each band and each part are measured, the bands and parts deviated from the distribution shape in a normal physiological state are specified, and a vibration waveform having the distribution of the instantaneous amplitude and instantaneous frequency in that band in a normal physiological state is input to any one of the driving devices of the left and right carotid bifurcations and the left and right vertebral arteries related to that band and part, and by bringing the blood flow in the corresponding part closer to a normal state, the abnormality of the autonomic nervous system can be improved.

[0019] When there are a plurality of bands deviated from the distribution shape in the normal physiological state at a specific part, the vibration waveform in the normal physiological state input to the driving device may be a superposition of the vibration waveforms of a plurality of bands.

Advantages of the Invention

[0020] According to the present embodiment, it is possible to provide a physiological state control system, a physiological state control method, and a vibration wave calculation program that can bring the autonomic nervous system closer to normal while reducing the load on a living body.

Brief Description of the Drawings

[0021]

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[0022] Hereinafter, this embodiment will be described through the present disclosure, but the scope of the claims is not limited to the following embodiments. Also, not all of the configurations described in the embodiments are essential as means for solving the problems. For clarification of the description, the following description and drawings are appropriately omitted and simplified. In each drawing, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted as necessary.

[0023] (Embodiment 1) The physiological state control system according to Embodiment 1 will be described. The physiological state control system of this embodiment acquires waveform information related to a living body such as an electroencephalogram waveform and a pulse wave waveform, and calculates a vibration wave to be applied to the living body based on the acquired waveform information. The pulse wave waveform may be a photoplethysmogram waveform or a piezoelectric waveform detecting pulse pressure. It may also be a Doppler effect processing waveform in which ultrasonic waves are reflected by the arterial wall, or time-series data of arterial diameters calculated from an arterial cross-sectional video by ultrasonic tomography. The electroencephalogram is measured simultaneously at a plurality of sites on the head by the 10-20 method or the like. The living body is, for example, a human subject. For example, the physiological state control system acquires waveform information of a normal physiological state related to the living body, calculates the characteristic amounts of a predetermined vibration wave with a set center frequency and amplitude, and records the characteristic amounts of the normal physiological state (the average values of the amplitudes and frequencies in each frequency band, and the variance values of the amplitudes and frequencies). Then, the physiological state control system calculates the characteristic amounts of the vibration wave in the current physiological state, and compares them with the characteristic amounts of the vibration wave in the normal physiological state (the average values of the amplitudes and frequencies in each frequency band, and the variance values of the amplitudes and frequencies), and applies a vibration wave from the outside of the living body that compensates for the characteristic amounts with differences to control the physiological state of the living body. Hereinafter, first, <Configuration of the physiological state control system> will be described. Then, <Physiological state control method> using the physiological state control system will be described.

[0024] <Configuration of the physiological state control system> FIG. 1 is a diagram illustrating the configuration of the physiological state control system according to Embodiment 1. As shown in FIG. 1, the physiological state control system 1 includes an electroencephalogram measuring device 10, a pulse wave measuring device 20, a driving device 30, and a physiological state control device 50. Those that acquire waveform information related to a living body, such as the electroencephalogram measuring device 10 and the pulse wave measuring device 20, are called waveform measuring devices.

[0025] The electroencephalogram measuring device 10 acquires the electroencephalogram of a living body as waveform information regarding the living body. The electroencephalogram measuring device 10 includes a sensor 11 and a main body unit 12. The sensors 11 are arranged at a plurality of sites according to the 10-20 method or the like and are measured simultaneously by the main body unit 12. The sensor 11 is, for example, attached to the scalp of a human head and senses information on the electroencephalogram of a human from outside the living body. Information on the electroencephalogram of a human is, for example, voltage. Note that the sensor 11 may sense current, magnetic field, etc. in addition to voltage as information on the electroencephalogram of a human. The sensor 11 is non-invasively attached to the living body.

[0026] The sensor 11 outputs the sensed electroencephalogram information to the main body unit 12 of the electroencephalogram measuring device 10. The main body unit 12 of the electroencephalogram measuring device 10 measures the time change of voltage or the like output from the sensor 11. The sensor 11 is connected to the main body unit 12 by a wired or wireless communication line. Further, the main body unit 12 is connected to the physiological state control device 50 by a wired or wireless communication line. The main body unit 12 outputs the measured electroencephalogram to the physiological state control device 50.

[0027] The pulse wave measuring device 20 measures the pulse wave of a living body as waveform information regarding the living body. The pulse wave is waveform information of a living body formed by the pulse interval, the blood ejection volume, and the physical characteristics of blood vessels. The pulse wave measuring device 20 includes a sensor 21 and a main body unit 22. The pulse wave measuring device 20 may be a photoelectric type or a piezoelectric type. In the case of a photoelectric type, near-infrared light with a wavelength of 800 to 1000 nm is preferable. The sensor 21 is, for example, attached to the skin on a human neck (carotid bifurcation) or cervical vertebra (vertebral artery) and measures information on the pulse wave flowing into the human brain from outside the living body. Specifically, the sensor 21 may be arranged at least in the vicinity of the left and right carotid bifurcations and / or in the vicinity of the left and right vertebral arteries (cervical vertebrae). Information on the pulse wave of a human is, for example, pulse pressure. Note that the sensor 21 may sense blood flow volume, etc. in addition to pulse pressure as information on the pulse wave of a human. The sensor 21 is non-invasively attached to the living body.

[0028] The sensor 21 outputs the detected pulse wave information to the main body 22 of the pulse wave measuring device 20. The main body 22 of the pulse wave measuring device 20 measures the time changes such as pulse pressure output from the sensor 21. The sensor 21 is connected to the main body 22 by a wired or wireless communication line. Also, the main body 22 is connected to the physiological state control device 50 by a wired or wireless communication line. The main body 22 outputs the measured pulse wave to the physiological state control device 50.

[0029] The driving device 30 applies the vibration wave calculated by the physiological state control device 50 to at least one of the vicinity of the left and right internal carotid arteries (arteries flowing into the brain from the carotid artery bifurcation) and the left and right vertebral arteries (arteries flowing into the brainstem along the cervical vertebrae) that supply blood from outside the living body to the brain. The driving device 30 includes a vibrator 31 and a main body 32. The vibrator 31 is attached, for example, to the skin on a human neck or collarbone or cervical vertebra (where the vertebral artery passes along the cervical vertebra) to apply a vibration wave to the human. Specifically, the vibrator 31 may be arranged in at least one of the vicinity of the left and right carotid artery bifurcations and the vicinity of the vertebral artery (cervical vertebra). In this case, the driving device 30 applies the calculated vibration wave from outside the living body to at least one of the left and right carotid artery bifurcations and the left and right vertebral arteries (cervical vertebra) of the living body. Thereby, the pulse wave of the living body is changed. One or a plurality of vibrators 31 may be attached to the living body. The vibrator 31 is non-invasively attached to the living body.

[0030] The vibrator 31 is connected to the main body 32 by a wired or wireless communication line. Also, the main body 32 is connected to the drive device 30 by a wired or wireless communication line. The main body 32 receives the vibration wave information calculated by the physiological state control device 50 from the physiological state control device 50. The vibration wave information input to the drive device is, for example, the average values of the amplitude and frequency in the vibration wave, and the variance values of the amplitude and frequency. The amplitude and frequency of at least one of the bands in the VLF2, VLF1, LF, HF, δ1, δ2, θ, α, β, γ bands of the vibration wave are distributed in a Gaussian-like manner. The main body 32 amplifies the vibration wave information received from the physiological state control device 50 and drives the vibrator 31. The vibrator 31 can apply vibrations obtained by superimposing arbitrary waveforms of a plurality of bands to the living body, and applies the vibration wave from the outside of the living body. In this way, the drive device 30 applies the vibration wave from the outside of the living body to at least one of the left and right carotid artery bifurcations and the left and right vertebral arteries (cervical vertebrae) of the living body.

[0031] Based on the waveform information acquired by the waveform measuring instrument, the physiological state control device 50 stores the characteristic quantities of the vibration wave of the living body in a normal physiological state. The characteristic quantities are the average values of the amplitude and frequency in the vibration wave, and the variance values of the amplitude and frequency. The vibration wave is, that is, a waveform passed through a band-pass filter in the bands of VLF2, VLF1, LF, HF, δ1, δ2, θ, α, β, γ, and when the probability density distributions of its amplitude and its frequency are calculated during a period that can be regarded as a physiologically steady state, each is distributed in a Gaussian-like manner. Then, when autonomic nerve disorder symptoms appear, similar characteristic quantities are calculated, the differences from the characteristic quantities in a normal physiological state are detected, and a vibration waveform is generated to compensate for the differences. By inputting the vibration waveform to the drive device and driving the vibrator 31, the blood flow flowing into the brain is brought closer to a normal state, and the autonomic nerve disorder symptoms are improved.

[0032] Specifically, it is assumed that due to autonomic nervous system disorder, the average of the amplitude distribution in a certain band of the pulse wave of the right internal carotid artery changes from M0 to M1, and the variance changes from S0 to S1, and the average of the frequency distribution changes from m0 to m1, and the variance changes from s0 to s1. At this time, in the electroencephalogram, if a site with similar modulation of the amplitude and frequency distribution in that band is found in the right temporal lobe, parietal lobe, and frontal lobe, while monitoring the degree of recovery of the modulation, the vibrator 31 is applied to the right internal carotid artery part to give vibrations that approximate the average of the amplitude distribution from M1 to M0, the variance from S1 to S0, the average of the frequency from m1 to m0, and the variance from s1 to s0. By doing so, the symptoms of autonomic nervous system disorder can be improved. The reason for not immediately giving the vibration distribution in the normal physiological state is to avoid imposing a load on the living body. The same applies even if the arterial system through which blood flows into the brain and the band that causes modulation are different. Also, when modulation occurs simultaneously in multiple bands, the vibration distribution waveforms for improving the modulated bands may be superimposed and applied to the desired vibrator.

[0033] FIG. 2 is a block diagram illustrating the physiological state control device 50 according to Embodiment 1. As shown in FIG. 2, the physiological state control device 50 includes a control unit 50a, a communication unit 50b, a storage unit 50c, an interface unit 50d, a waveform information acquisition unit 51, a filtering unit 52, a conversion unit 53, an instantaneous value calculation unit 54, a distribution calculation unit 55, and a vibration wave calculation unit 56. The control unit 50a, the communication unit 50b, the storage unit 50c, the interface unit 50d, the waveform information acquisition unit 51, the filtering unit 52, the conversion unit 53, the instantaneous value calculation unit 54, the distribution calculation unit 55, and the vibration wave calculation unit 56 each have functions as control means, communication means, storage means, interface means, waveform information acquisition means, filtering means, conversion means, instantaneous value calculation means, distribution calculation means, and vibration wave calculation means.

[0034] The physiological state control device 50 is an information processing device including a computer. The control unit 50a includes processors such as a CPU (Central Processing Unit), an MPU (Micro Processing Unit), an ECU (Electronic Control Unit), an FPGA (Field-Programmable Gate Array), and an ASIC (Application Specific Integrated Circuit). The control unit 50a has a function as an arithmetic unit that performs control processing, arithmetic processing, and the like. Further, the control unit 50a controls the operations of each component such as a communication unit 50b, a storage unit 50c, an interface unit 50d, a waveform information acquisition unit 51, a filtering unit 52, a conversion unit 53, an instantaneous value calculation unit 54, a distribution calculation unit 55, and a vibration wave calculation unit 56.

[0035] Each component of the physiological state control device 50 can be realized, for example, by causing a program to be executed under the control of the control unit 50a. More specifically, each component can be realized by the control unit 50a executing a program stored in the storage unit 50c. Further, by recording a necessary program on an arbitrary non-volatile recording medium and installing it as needed, each component may be realized. Further, each component is not limited to being realized by software based on a program, and may be realized by any combination of hardware, firmware, and software.

[0036] The communication unit 50b receives waveform information measured by waveform measuring devices such as an electroencephalograph 10 and a pulse wave measuring device 20 from the waveform measuring devices. The waveform information is, for example, time series data of electroencephalograms and pulse waves. The communication unit 50b transmits the information of the vibration wave calculated by the vibration wave calculation unit 56 to the drive device 30.

[0037] The storage unit 50c may have a storage device such as a memory or a hard disk, for example. The storage device is, for example, a ROM (Read Only Memory) or a RAM (Random Access Memory), etc. The storage unit 50c has a function for storing control programs, arithmetic programs, etc. executed by the control unit 50a. Further, the storage unit 50c has a function for temporarily storing processing data, etc.

[0038] The storage unit 50c may store waveform information such as brain waves and pulse waves received by the communication unit 50b. The storage unit 50c may store the vibration waves calculated by the vibration wave calculation unit 56. The storage unit 50c may store various parameters used by the vibration wave calculation unit 56 for calculating the vibration waves.

[0039] The interface unit 50d is, for example, a user interface (User Interface). The interface unit 50d has an input device such as a keyboard, a touch panel, or a mouse, and an output device such as a display or a speaker. The interface unit 50d receives an operation of inputting data by a user (operator, etc.) and outputs information to the user.

[0040] The waveform information acquisition unit 51 acquires the waveform information obtained by the communication unit 50b from the waveform measuring device. The filtering unit 52 filters the acquired waveform information in at least one frequency band. The conversion unit 53 performs a conversion to complexify the waveform information in the filtered frequency band. The conversion to complexify is, for example, a Hilbert transform. The instantaneous value calculation unit 54 calculates an instantaneous value including at least any one of the amplitude term corresponding to the real part of the complex waveform obtained by complexifying the pulse wave and electroencephalogram waveform information as the instantaneous amplitude, the time differential value of the phase term corresponding to the imaginary part as the instantaneous frequency, and the instantaneous phase difference corresponding to the difference between the phase terms of the electroencephalogram and the pulse wave. The distribution calculation unit 55 calculates the probability density distribution of the instantaneous value. Further, the distribution calculation unit 55 calculates a Gaussian distribution fitted to the probability density distribution. The vibration wave calculation unit 56 calculates the information of the vibration wave so that the calculated Gaussian distribution becomes a predetermined Gaussian distribution. The vibration wave calculation unit 56 outputs the calculated information of the vibration wave to the communication unit 50b. The information of the vibration wave includes the amplitude and the center frequency. The communication unit 50b outputs the information of the vibration wave to the driving device 30 to drive the vibrator 31.

[0041] <Physiological state control method> Next, the physiological state control method will be described. FIG. 3 is a flowchart illustrating the physiological state control method according to Embodiment 1. As shown in FIG. 3, the physiological state control method includes a step of acquiring waveform information regarding a living body (step S11), a step of calculating a vibration wave to be applied to the living body (step S12), and a step of applying the vibration wave from outside the living body (step S13).

[0042] As shown in step S11 of FIG. 3, first, waveform information regarding a living body is acquired. For example, waveform measuring devices such as the electroencephalogram measuring device 10 and the pulse wave measuring device 20 acquire electroencephalograms, pulse waves, etc. as waveform information regarding the living body.

[0043] FIG. 4 is a graph exemplifying waveform information related to a living body according to Embodiment 1. The horizontal axis represents time, and the vertical axis represents intensity. FIG. 4 shows time-series data of a pulse wave as an example of waveform information related to a living body. Note that the waveform information related to a living body is not limited to the time-series data of a pulse wave, and may be the time-series data of an electroencephalogram or the time-series data of an inter-pulse interval (resampled at a desired frequency). The pulse wave measuring device 20 acquires time-series data of a pulse wave, for example, via a sensor 21 disposed at the bifurcation of the left and right carotid arteries or the left and right vertebral arteries of a subject. For example, the pulse wave of a subject in a steady state is measured for several minutes to several tens of minutes. The sampling frequency is, for example, 500 Hz. Note that the sampling frequency can adopt any frequency between 10 and 1000 Hz. The pulse wave data obtained in this way becomes a time-series waveform as shown in FIG. 4. The waveform measuring device outputs the acquired waveform information to the physiological state control device 50.

[0044] Next, as shown in step S12, a vibration wave to be applied to the living body is calculated. The physiological state control device 50 calculates a vibration wave to be applied to the living body based on the acquired waveform information. The method for calculating the vibration wave will be described later. The physiological state control device 50 outputs the information of the calculated vibration wave to the driving device 30.

[0045] Next, as shown in step S13, the calculated vibration wave is applied from the outside of the living body. For example, the driving device 30 generates a vibration wave in the vibrator 31 based on the information of the vibration wave output from the physiological state control device 50. Thereby, the vibrator 31 applies the calculated vibration wave from the outside of the living body to at least any one of, for example, the bifurcation of the right carotid artery on the left side of the living body, the bifurcation of the right carotid artery on the right side, the left vertebral artery, and the right vertebral artery.

[0046] <Method for Calculating Vibration Wave> Next, the method for calculating the vibration wave in step S12 described above will be explained. FIG. 5 is a flowchart illustrating the method for calculating the vibration wave performed by the physiological state control device 50 according to Embodiment 1. As shown in FIG. 5, the method for calculating the vibration wave includes a waveform information acquisition step (step S21) of acquiring waveform information regarding a living body, a filtering step (step S22) of filtering the acquired waveform information in at least one frequency band, a conversion step (step S23) of complexifying and converting the waveform information in the filtered frequency band, an instantaneous value calculation step (step S24) of calculating an instantaneous value including at least any one of an instantaneous amplitude, an instantaneous frequency, and an instantaneous phase, a distribution calculation step (step S25) of calculating the distribution of the instantaneous values, and a vibration wave calculation step (step S26) of calculating a vibration wave to be applied to the living body so that the calculated distribution becomes a predetermined distribution. The steps from S21 to S25 are calculated in a normal physiological state, and the numerical values are stored in the storage unit 50c. Hereinafter, each step will be explained.

[0047] <Waveform Information Acquisition Step> The waveform information acquisition unit 51 of the physiological state control device 50 acquires the waveform information received by the communication unit 50b from waveform measuring devices such as the electroencephalograph 10 and the pulse wave measuring device 20. The waveform information acquisition unit 51 acquires, for example, an electroencephalogram waveform and a pulse wave waveform from the time series data of the electroencephalogram and the pulse wave.

[0048] <Filtering Step> FIG. 6 is a graph illustrating signal waveforms obtained by filtering a pulse wave as waveform information related to a living body according to Embodiment 1 in each frequency band. The horizontal axis represents time, and the vertical axis represents intensity. In FIG. 6, HF, LF, VLF1, and VLF2 are shown as each frequency band. Further, a pulse interval waveform, which will be described later, is also shown in FIG. 6. FIG. 7 is a graph illustrating signal waveforms obtained by filtering an electroencephalogram as waveform information related to a living body according to Embodiment 1 in each frequency band. The horizontal axis represents time, and the vertical axis represents intensity. In FIG. 7, band waveforms of electroencephalograms (δ1, δ2, θ, α, β, γ) are shown as frequency bands shorter than the heartbeat interval. Further, BVP is also shown in FIG. 7. FIG. 8 is a diagram illustrating each frequency band in the case of filtering waveform information related to a living body according to Embodiment 1. In FIG. 8, approximate center frequencies in several frequency bands are also shown.

[0049] As shown in FIGS. 6 and 7, the filtering unit 52 of the physiological state control device 50 filters the acquired waveform information in at least one frequency band. Specifically, the filtering unit 52 of the physiological state control device 50 filters the waveform information acquired by the waveform information acquisition unit 51 for each frequency band.

[0050] As shown in FIGS. 6 to 8, for example, VLF2 (0.004 to 0.015 Hz), VLF1 (0.015 to 0.04 Hz), LF (0.04 to 0.15 Hz), HF (0.15 to 0.4 Hz), δ1 (0.4 to 1.5 Hz), δ2 (1.5 to 4 Hz), θ (4 to 8 Hz), α (8 to 13 Hz), β (13 to 30 Hz), and γ (30 to 100 Hz) etc. are selected as the frequency bands to be filtered. Here, VLF1 and VLF2 are frequency bands related to the functions of the autonomic nerves such as body temperature regulation, digestion, excretion, reproduction, and immunity, HF is the respiratory fluctuation band, and LF is the blood pressure fluctuation band. Signals in frequency bands higher than these ride on the pulse waves flowing into the brain from the vertebral artery branching from the internal carotid artery and the subclavian artery at the carotid bifurcation, and include the bands of δ wave (0.4 to 4.0 Hz), θ wave (4.0 to 8.0 Hz), α wave (8.0 to 13.0 Hz), β wave (13.0 to 30.0), and γ wave (30 to 100 Hz) in the electroencephalogram.

[0051] FIG. 9 is a graph illustrating a signal waveform obtained by Fourier-transforming waveform information measured by a generally commercially available pulse waveform. The horizontal axis represents the frequency, and the vertical axis represents the spectral power. Since there is a high-pass filter near 0.1 Hz, signals with frequencies below 0.1 Hz are lost. Also, since green light is irradiated on the blood vessels and the reflected light amount is used as the pulse wave signal, only information on the capillaries on the skin surface can be obtained and it cannot be used in this embodiment. To be used in this embodiment, it is necessary to have at least a frequency band width of 0.001 to 100 Hz and observe the pulse wave signal of the artery at a depth of 2 to 3 cm from the skin with near-infrared light (wavelength 800 - 1000 nm). Furthermore, to cover a wide frequency band of the living body and observe the pulse wave of the vertebral artery located deeper than the carotid artery, it is necessary to have at least a frequency band width of 0.0001 to 400 Hz and observe the pulse wave signal of the artery at a depth of 2 to 5 cm from the skin with near-infrared light (wavelength 800 - 1600 nm).

[0052] Although the display of the electroencephalogram waveform in the figure is omitted, filtering can be performed in a frequency band similar to the pulse wave waveform.

[0053] <Conversion Step> Next, the physiological state control device 50 performs a Hilbert transform that complexifies the waveform information of each frequency band that has been filtered. Specifically, the conversion unit 53 of the physiological state control device 50 performs a Hilbert transform on the time-series data φ k (t) and other waveform information of the filtered waveforms in each frequency band as shown in FIGS. 6 and 7 into a complex wave form as shown in the following formula (1).

[0054] φ k (t) = exp(a k (t) + iψ k (t)) (1) Here, a k (t) is the instantaneous value of the logarithmic amplitude of the k-frequency band waveform, and ψ k (t) is the instantaneous value of the phase of the k-frequency band waveform.

[0055] FIG. 10 is a diagram showing in the complex plane the complex wave form obtained by performing a Hilbert transform on the waveform information regarding the living body according to Embodiment 1. As shown in FIG. 10, the waveform information (vibration) represented in the complex wave form can be represented on the complex plane. When the horizontal axis in the complex plane is Re(ln φ(t)) and the vertical axis is Im(ln φ(t)), a k (t) indicates the radius centered on the origin, and ψ k (t) indicates the angle with the horizontal axis. Here, k = 1, 2, 3, 4 ··· indicates each frequency band.

[0056] The Hilbert transform is performed on each frequency band waveform of the pulse wave waveform and the electroencephalogram waveform.

[0057] <Instantaneous value calculation step> Next, the instantaneous value calculation unit 54 of the physiological state control device 50 calculates the instantaneous value. The instantaneous value includes at least any one of the instantaneous logarithmic amplitude, the instantaneous frequency which is the time differential value of the instantaneous phase, and the instantaneous phase difference. Here, the instantaneous phase difference is the difference in the instantaneous phases between the pulse wave and the brain wave, or the difference in the instantaneous phases between the pulse wave and the heart rate interval. The instantaneous logarithmic amplitude corresponds to the logarithmic real part of the complex wave form obtained by performing the Hilbert transform on the waveform information. The instantaneous frequency corresponds to the time differential value of the logarithmic imaginary part of the complex wave form. The instantaneous phase difference corresponds to the difference in the imaginary term of the logarithm of the complex conversion formula between the brain wave and the pulse wave. Specifically, the instantaneous logarithmic amplitude, the instantaneous frequency, and the instantaneous phase difference are defined by the following equations (2), (3), and (4).

[0058] By performing the processing of equation (1) on the pulse wave data, the instantaneous logarithmic amplitude and the instantaneous frequency of equations (2) and (3) can be obtained.

[0059] a k (t) (2)

[0060] ω k (t)=dψ k (t) / dt (3)

[0061] By performing the processing of equation (1) on the brain wave data, the instantaneous logarithmic amplitude and the instantaneous frequency of equations (4) and (5) can be obtained.

[0062] Ak(t) (4)

[0063] Ω k (t)=dΨ k (t) / dt (5)

[0064] As the instantaneous phase difference between the time series data of the brain wave and the pulse wave θ k (t)=Ψk(t)-ψk(t) (6) This indicates the phase relationship in which the blood flow supplied to the brain is consumed at each center in the brain, and becomes an important feature quantity for knowing the physiological state of each center. When the distribution of θk(t) follows a random process, it can be approximated by the Von Mises distribution shown in equation (7). Here, I j (κ) is the Bessel function of the first kind of the j-th order f(θ)=exp(κ cos(θ - μ)) / 2πI0(κ) (7) I j (κ)=(κ / 2) j Σ(κ 2 / 4) i / i!Γ(j + i + 1) (8)

[0065] In this way, the instantaneous value calculation unit 54 calculates an instantaneous value including at least any one of the instantaneous logarithmic amplitude a k (t), Ak(t) corresponding to the real part of the exponential part of the complex wave form obtained by Hilbert-transforming the waveform information, the instantaneous frequency ω k (t), Ω k (t) corresponding to the time derivative value of the imaginary part thereof, and the instantaneous phase difference θ k (t) corresponding to the phase difference of the band waveforms of the brain wave and the pulse wave.

[0066] <Distribution calculation> Next, the distribution calculation unit 55 of the physiological state control device 50 calculates the distribution of the instantaneous values of the pulse wave and the brain wave. Specifically, the distribution calculation unit 55 calculates the probability density distribution of the instantaneous logarithmic amplitude a k (t), Ak(t), the instantaneous frequency ω k (t), Ω k (t), and the instantaneous phase difference θ k (t). Also, the distribution calculation unit 55 fits the distribution shape of the instantaneous logarithmic amplitude a k (t), Ak(t), the instantaneous frequency ω k (t), Ω k (t), and the instantaneous phase difference θ k (t) to a unimodal distribution, for example, a Gaussian probability density distribution, in a time interval that can be regarded as a desired physiological steady state in a normal physiological state and a state with autonomic nervous system disorder symptoms, and acquires and stores it in the storage unit 50c. Here, since the value of the instantaneous phase difference is limited to the range of -π to +π, for example, the Von Mises distribution is applied.

[0067] FIG. 11 is a diagram illustrating the probability density distribution of instantaneous values and the Gaussian distribution according to Embodiment 1. The bar graph shows the probability density distribution, and the solid line shows the Gaussian distribution. FIG. 11(a) shows the probability density distribution and the Gaussian distribution of the instantaneous logarithmic amplitude of HF, and FIG. 11(b) shows the probability density distribution and the Gaussian distribution of the instantaneous logarithmic amplitude of LF. FIG. 11(c) shows the probability density distribution and the Gaussian distribution of the instantaneous logarithmic frequency of HF, and FIG. 11(d) shows the probability density distribution and the Gaussian distribution of the instantaneous frequency of LF. The mean value and variance value of each Gaussian distribution are also shown. Similarly, the mean value and variance value are shown in the following diagrams of Gaussian distributions. It can be seen that the logarithmic amplitude and frequency of one oscillator are distributed in a Gaussian-like manner for each band. FIG. 12 shows the probability density distribution of the instantaneous phase difference between the HF and LF bands according to Embodiment 1, and the solid line shows the Von Misese distribution. FIGS. 13 and 14 show the probability density distributions of the logarithmic amplitude, frequency, and phase difference between the brain wave and the pulse wave in the θ and α bands according to Embodiment 1. The solid line in the diagrams of the logarithmic amplitude and frequency is the Gaussian distribution, and the solid line in the diagram of the phase difference shows the Von Misese distribution. Although the figures are omitted for frequencies higher than 12 Hz, the β and γ bands, the logarithmic amplitude and frequency of each signal waveform are distributed in a Gaussian-like manner, respectively.

[0068] FIGS. 15 and 16 are diagrams illustrating the probability density distribution and the Gaussian distribution of the instantaneous frequency in the brain wave (frontal lobe) of the left brain during eyes-open rest according to Embodiment 1. FIG. 15(a) shows HF, FIG. 15(b) shows LF, FIG. 15(c) shows θ waves, and FIG. 15(d) shows α waves. FIG. 16(a) shows β waves, and FIG. 16(b) shows γ waves. FIGS. 17 and 18 are diagrams illustrating the probability density distribution and the Gaussian distribution of the instantaneous frequency in the brain wave of the right brain during eyes-open rest according to Embodiment 1. FIG. 17(a) shows HF, FIG. 17(b) shows LF, FIG. 17(c) shows θ waves, and FIG. 17(d) shows α waves. FIG. 18(a) shows β waves, and FIG. 18(b) shows γ waves.

[0069] Figures 19 and 20 are diagrams illustrating the probability density distributions and Gaussian distributions of the instantaneous frequencies in the electroencephalogram (frontal lobe) of the left brain during eyes-closed rest according to Embodiment 1. In Fig. 19(a), HF is shown, in Fig. 19(b), LF is shown, in Fig. 19(c), theta waves are shown, and in Fig. 19(d), alpha waves are shown. In Fig. 20(a), beta waves are shown, and in Fig. 20(b), gamma waves are shown. Figures 21 to 22 are diagrams illustrating the probability density distributions and Gaussian distributions of the instantaneous frequencies in the electroencephalogram of the right brain during eyes-closed rest according to Embodiment 1. In Fig. 21(a), HF is shown, in Fig. 21(b), LF is shown, in Fig. 21(c), theta waves are shown, and in Fig. 21(d), alpha waves are shown. In Fig. 22(a), beta waves are shown, and in Fig. 22(b), gamma waves are shown.

[0070] As shown in Figs. 15 to 18, during eyes-open rest, generally, it is an awake state and a state of decreased parasympathetic nerve activity. Therefore, during eyes-open rest, it is a so-called energetic state. For example, as shown in Figs. 15(c) and 17(c), the central frequency of the theta waves during eyes-open rest shifts to a lower frequency side than the central frequencies of the theta waves during eyes-closed rest shown in Figs. 19(c) and 21(c). Also, as shown in Figs. 15(d) and 17(d), the central frequency of the alpha waves during eyes-open rest shifts to a higher frequency side than the central frequencies of the alpha waves during eyes-closed rest shown in Figs. 19(d) and 21(d).

[0071] On the other hand, as shown in Figs. 19 to 22, during eyes-closed rest, generally, it is a resting state and a state of increased parasympathetic nerve activity. Therefore, during eyes-closed rest, it is a so-called relaxed state. For example, as shown in Figs. 19(c) and 21(c), the central frequency of the theta waves during eyes-closed rest shifts to a higher frequency side than the central frequencies of the theta waves during eyes-open rest shown in Figs. 15(c) and 17(c). Also, as shown in Figs. 19(d) and 21(d), the central frequency of the alpha waves during eyes-closed rest shifts to a lower frequency side than the central frequencies of the alpha waves during eyes-open rest shown in Figs. 15(d) and 17(d).

[0072] <Vibration wave calculation> Next, the physiological state control device 50 examines the differences in the characteristic quantities of the distributions of each band between the time when autonomic nerve disorder appears and the time of normal physiological state, and calculates vibration waves that bring the distribution closer to a normal distribution. For example, assume that due to autonomic nerve disorder, the average of the amplitude distribution of a certain band of the pulse wave of the right internal carotid artery changes from M0 to M1, the variance changes from S0 to S1, the average of the frequency distribution changes from m0 to m1, and the variance changes from s0 to s1. At this time, in the electroencephalogram, if sites with similar amplitude and frequency distribution modulation in that band are found in the right temporal lobe, parietal lobe, and frontal lobe, while monitoring the degree of recovery of the modulation, the vibrator 31 is applied to the right internal carotid artery part to make the average of the amplitude distribution approach from M1 to M0, the variance approach from S1 to S0, the average of the frequency approach from m1 to m0, and the variance approach from s1 to s0, and give vibrations. By doing so, the symptoms of autonomic nerve disorder can be improved. The reason for not immediately giving the vibration distribution of the normal physiological state is to avoid imposing a burden on the living body. The same applies even if the arterial system through which blood flows into the brain and the frequency band causing modulation are different. The vibration waves may be superimposed for each frequency band (k = 1, 2, 3, 4 ···). The vibration wave calculation unit 56 may calculate the amplitude and center frequency of the vibration wave of a predetermined Gaussian distribution as the amplitude and center frequency of the vibration wave to be applied to the living body.

[0073] Samples of the time-series data of the instantaneous pulse wave amplitude and instantaneous pulse wave frequency for each band in the normal physiological state are shown in FIGS. 28 and 29. For each band, the instantaneous pulse wave amplitude and instantaneous frequency data are acquired at time intervals that result in a Gaussian-like distribution in the physiologically steady state, and time-series data in which the instantaneous amplitude and instantaneous frequency change continuously are generated using the waveforms. At this time, at least the second-order time differential values are made to match at the start point and end point of the time-series data and connected, and an annular vibration waveform is generated using this sample data. If the average value and variance value of this sample data are different from the desired values, differential addition of the average value and ratio multiplication of the variance value are performed so that the average value and variance value become the desired numerical values. When applying vibration waveforms in multiple bands, the vibration waveforms are calculated for each band according to the above procedure, a waveform obtained by superimposing them is generated, and it is input to the drive device 30.

[0074] The normal vibration waveform may be input to the drive device 30 after being approximated by a mathematical function so as to have a desired average value and variance value. In this case, it is necessary to ensure that at least the second-order time derivative value is continuous.

[0075] When the autonomic nerve disorder is relatively mild and the difference from the normal state is small, the vibration waveform in the different band may be made the same as that in the normal physiological state and applied to the oscillator 31 from the beginning.

[0076] When the calculated vibration wave is applied to the vertebral artery branching from the left and right carotid artery bifurcations or the left and right subclavian arteries, the pulse pressure vibration wave can be superimposed on the cerebral blood flow via the carotid artery or the vertebral artery. Brain activities include the activities of the central nervous system of the autonomic nervous system in the bands of VLF2 (0.004 - 0.015 Hz), VLF1 (0.015 - 0.04 Hz), LF (0.04 - 0.15 Hz), and HF (0.15 - 0.4 Hz) in the brainstem, and various central activities in the frequency bands of δ wave (0.4 - 4.0 Hz), θ wave (4.0 - 8.0 Hz), α wave (8.0 - 13.0 Hz), β wave (13.0 - 30.0 Hz), and γ wave (30 - 100 Hz) in the cerebrum (cortex, limbic system). Therefore, the physiological state control system 1 measures the brain waves and generates a vibration wave that becomes a pulse pressure signal to assist the brain wave activities in each band. Then, the physiological state control system 1 applies the generated vibration wave from the carotid artery bifurcation through the internal carotid artery to the frontal lobe, temporal lobe, and parietal lobe, and from the vertebral artery through the brainstem to the cerebellum and occipital lobe. Thereby, the physiological state control system 1 can assist the brain activities and support and activate the brain activities in each frequency band.

[0077] Also, as an example of calculating the vibration wave, it may be calculated from the 1 / f equal energy surface (also called the 1 / f spectrum). Hereinafter, the method of calculating from the 1 / f equal energy surface will be described.

[0078] <1 / f equal energy surface> FIG. 23 and FIG. 24 are diagrams exemplifying complex conversion formulas in each frequency band according to Embodiment 1 in three dimensions. The horizontal axis and the vertical axis in the complex plane indicate Re(ln φ(t)) and Im(ln φ(t)) of the complex conversion formula, and the axis orthogonal to the complex plane indicates the frequency (energy axis). For example, for a frequency band longer than the heartbeat interval, k = 4 is represented as HF (respiration), k = 3 as LF (blood pressure), k = 2 as VLF1 (possibly related to the autonomic nerve), and k = 1 as VLF2 (possibly related to the autonomic nerve). For the brain wave band, k = 5 is the δ1 wave, k = 6 is the δ2 wave, k = 7 is the θ wave, k = 8 is the α wave, and so on. Then, the radius in the complex plane becomes the logarithmic amplitude of each frequency band waveform, the energy axis becomes the frequency axis, and the rotation direction around the energy axis corresponds to the phase angle between the pulse wave and the pulse interval waveform in the case of FIG. 23, and the phase angle between the pulse wave and the brain wave in the case of FIG. 24. And a pattern of rotating around the energy axis while being distributed in a Gaussian-like manner on each axis is observed. In this way, an image is obtained as if orbiting around the nucleus like an electron cloud in which electrons at each energy level are represented by the probability of existence. And the Gaussian-like distribution of each frequency band similar to the electron cloud is formed along the 1 / F equal energy surface.

[0079] Therefore, the vibration wave calculation unit 56 of the physiological state control device 50 may use a Gaussian distribution along the 1 / F equal energy surface as a predetermined Gaussian distribution. That is, the vibration wave calculation unit 56 may calculate the vibration wave so that the Gaussian distribution of the acquired waveform information becomes a Gaussian distribution along the 1 / F equal energy surface.

[0080] FIG. 25 shows the measurement result of cerebral blood flow by optical topography technology (NIRS) measured in the frontal lobe. It is a graph exemplifying the relationship between the total hemoglobin concentration (o2hb + hhb) and the frequency. The horizontal axis indicates the frequency, and the vertical axis indicates the total hemoglobin concentration. As shown in FIG. 25, the frequency spectrum of the total hemoglobin concentration (o2hb + hhb) lies on the 1 / f line. Therefore, it is considered that the fluctuation spectrum of blood flow rides on 1 / f.

[0081] When applying vibrations below HF (below 0.4 Hz) to blood vessels, vibrations with larger amplitudes must be applied as the frequency decreases. Therefore, it is impossible to perform such an operation because applying vibrations with such large amplitudes to blood vessels may stop blood flow. To avoid this, when an AM modulation is performed on a vibration waveform in the range of several Hz to about 10 Hz with a vibration waveform of a low frequency and the low-frequency vibration waveform is superimposed, a low-frequency signal can be superimposed on the blood flow of the artery without stopping the blood flow of the artery.

[0082] In addition, the physiological state control system 1 can normalize the autonomic nervous system with respect to the modulation of physiological states such as circadian variation and diurnal variation by expanding to lower frequency bands such as frequencies lower than VLF2, ULF1 (1.5 to 4 mHz), and ULF2 (0.4 to 1.5 mHz) and processing waveform information in the same way as HF, LF, VLF1, and VLF2.

[0083] The physiological state control system 1, for example, sets the amplitude and the center frequency for each frequency band of the pulse wave based on the heartbeat fluctuation, and calculates a vibration wave that rides on a 1 / f spectrum having a Gaussian-like fluctuation. Then, by applying the calculated vibration wave to the carotid bifurcation or the vertebral artery, a pulse pressure vibration of the 1 / f spectrum can be given to the cerebral artery flow. Then, while feeding back the pulse wave and the brain wave, by optimizing the vibration wave, it is possible to assist or support the autonomic nerve or the brain activity so that the adjustment of the autonomic nerve or the brain wave activity is activated.

[0084] (Embodiment 2) Next, the physiological state control system according to Embodiment 2 will be described. The physiological state control system of this embodiment considers only the fluctuations of the autonomic nervous system that are longer than the cardiac cycle as waveform information regarding the living body. Therefore, it does not handle brain wave bands of 0.4 Hz or higher and uses only the pulse wave waveform. The pulse wave waveform may be a photoplethysmogram waveform, a piezoelectric waveform due to pulse pressure, a Doppler effect processing waveform obtained by reflecting ultrasonic waves on the arterial surface, or arterial diameter time series data calculated from an arterial cross-sectional video by ultrasonic tomography. Since signals in the band of 0.4 Hz or lower are generated by the heartbeat fluctuations of the heart under the control of the brainstem, the pulse wave may be acquired anywhere in the body. The photoplethysmogram does not need to use near-infrared light and may be a general green light one. However, it is necessary to use a signal waveform excluding a high-pass filter around 0.1 Hz such as a commercially available pulse wave sensor.

[0085] <Waveform information acquisition step> The waveform information acquisition unit 51 of the physiological state control device 50 acquires the waveform information received by the communication unit 50b from a waveform measuring device such as the pulse wave measuring device 20. The waveform information acquisition unit 51 acquires the pulse wave waveform from the time series data of the pulse wave.

[0086] FIG. 26 is a diagram illustrating the definition of the pulse wave waveform and the pulse interval according to Embodiment 2. FIG. 27 is a diagram illustrating the definition of the pulse interval wave according to Embodiment 2. As shown in FIG. 26, the pulse interval (PPI: Peak-Peak Interval) is calculated from the pulse wave waveform data B(t) using the pulse wave rising edge position detection algorithm presented by Non-Patent Document 1, and the rising time of the pulse wave and the pulse interval are plotted and spline-interpolated, whereby a pulse interval wave R(t) as shown in FIG. 27 is obtained. Therefore, a pulse interval wave as shown in FIG. 27 may be used as waveform information for calculating the vibration wave. That is, the physiological state control device 50 may calculate a vibration wave to be applied to the living body based on the pulse interval wave as waveform information.

[0087] <Filtering step> As frequency bands for filtering the pulse wave form and the pulse interval waveform, for example, VLF2 (0.004 to 0.015 Hz), VLF1 (0.015 to 0.04 Hz), LF (0.04 to 0.15 Hz), and HF (0.15 to 0.4 Hz) are selected. Here, VLF1 and VLF2 are variation bands related to the functions of the autonomic nerves such as body temperature regulation, digestion, excretion, reproduction, and immunity, and HF is a respiratory variation band. Also, LF is a blood pressure variation band.

[0088] When performing the same processing as in Embodiment 1, the instantaneous logarithmic amplitude of Equation (9) and the instantaneous frequency of Equation (10) are obtained from the pulse wave data. Note that the symbols in the equations of Embodiment 2 may have meanings different from those of the symbols in the equations of Embodiment 1.

[0089] a k (t) (9)

[0090] ω k (t)=dψ k (t) / dt (10)

[0091] The instantaneous logarithmic amplitude of Equation (11) and the instantaneous frequency of Equation (12) are obtained from the pulse interval data.

[0092] A k (t) (11)

[0093] Ω k (t)=dΨ k (t) / dt (12)

[0094] As the instantaneous phase difference between the pulse interval waveform and the time series data of the pulse wave, Equation (13) can be obtained. θ k (t)=Ψk(t)-ψk(t) (13)

[0095] In this way, the instantaneous value calculation unit 54 calculates the instantaneous logarithmic amplitude a k (t), A k (t) corresponding to the real part of the exponential part of the complex wave form obtained by Hilbert-transforming the waveform information, and the instantaneous frequency ω k (t), Ωk Calculate the instantaneous value including the phase difference θk(t) between the pulse interval and the pulse wave at time (t).

[0096] <Distribution calculation> Next, the distribution calculation unit 55 of the physiological state control device 50 calculates the distribution of the instantaneous values of the pulse wave and the pulse interval waveform. Specifically, the distribution calculation unit 55 calculates the instantaneous logarithmic amplitude a k (t), A k (t), the instantaneous frequency ω k (t), Ω k (t), and calculates the probability density distribution of the instantaneous phase difference θk(t) between the pulse wave and the pulse interval, fits these probability density distributions to, for example, a Gaussian distribution, obtains the distribution shapes of the respective instantaneous logarithmic amplitude, instantaneous frequency, and instantaneous phase difference, and stores them in the storage unit 50c. Here, since the value of the instantaneous phase difference is limited to the range of -π to +π, for example, the Von Mises distribution is applied.

[0097] <Vibration wave calculation> Next, the physiological state control device 50 examines the differences in the characteristic quantities of the distributions in each frequency band between when autonomic neuropathy appears and when in a normal physiological state, and calculates vibration waves that bring the distribution closer to a normal distribution. For example, assume that due to autonomic neuropathy, the average of the amplitude distribution in a certain frequency band of the pulse wave of VLF2 changes from M0 to M1, the variance changes from S0 to S1, the average of the frequency distribution changes from m0 to m1, and the variance changes from s0 to s1. The variation in the inter-beat interval in the frequency band below 0.4 Hz is caused by the function of the brainstem. Since the brain waves are not monitored, the pulse wave can be measured at the fingertip or the like to calculate the physiological characteristic quantities in each frequency band. While monitoring these numerical values, the vibrator 31 is applied to the left and right vertebral arteries that supply blood to the brainstem or the carotid artery bifurcation that supplies blood to the frontal lobe, temporal lobe, and parietal lobe, so as to make the average of the amplitude distribution approach from M1 to M0, the variance approach from S1 to S0, the average of the frequency approach from m1 to m0, and the variance approach from s1 to s0, thereby improving the autonomic neuropathy symptoms. The reason for not immediately giving the vibration distribution of the normal physiological state is to avoid imposing a load on the living body. The same applies even if the arterial system that flows into the brain and the frequency band that causes modulation are different. The vibration wave may be a superposition for each frequency band (k = 1, 2, 3, 4). The vibration wave calculation unit 56 may calculate the amplitude and center frequency of the vibration wave of a predetermined Gaussian distribution as the amplitude and center frequency of the vibration wave applied to the living body.

[0098] When applying vibrations below HF (below 0.4 Hz) to the blood vessels, there is a possibility that applying vibrations with a large amplitude may stop the blood flow. To avoid this, a signal obtained by AM modulating the vibration waveform at a low frequency below HF with a vibration waveform of several Hz to about 10 Hz is input to the driving device, and vibrations are externally applied to the vicinity of the vertebral arteries of the left and right cervical vertebrae or the vicinity of the bifurcation of the left and right carotid arteries via the vibrator. Here, since the vertebral artery supplies blood to the brainstem, a great effect can be expected due to autonomic neuropathy.

[0099] When the autonomic neuropathy is relatively mild and the difference from the normal state is small, the vibration waveform in the different band may be made the same as that in the normal physiological state and applied to the vibrator 31 from the beginning.

[0100] In addition, the pulse wave measurement sensor 21 needs to detect information on blood vessels several centimeters deep from the living body surface. Considering the absorption spectra of hemoglobin and water, which are the main light-absorbing substances present in the living body, it utilizes wavelengths in the range of 700 - 2000 nm, which is called the optical window. At the same time, it is necessary to be able to observe from 0.004 Hz, which is the lower limit of the VLF2 frequency, up to 200 Hz, which is twice the upper limit of brain waves, called gamma waves, up to 100 Hz, considering the Nyquist condition.

[0101] In addition, the physiological state control system 1 can normalize the autonomic nervous system with respect to the modulation of physiological states such as diurnal variation and daily variation by also expanding to lower frequency bands such as frequencies lower than VLF2, ULF1 (1.5 - 4 mHz), and ULF2 (0.4 - 1.5 mHz) and processing waveform information in the same way as LF and VLF.

[0102] Note that the present disclosure is not limited to the above embodiments, and can be appropriately changed without departing from the gist. For example, a combination of the configurations of Embodiments 1 and 2 is also included in the scope of the technical idea of this embodiment. Also, the following vibration wave calculation program for causing a computer to execute the calculation of the vibration wave performed by the physiological state control device 50 is included in the scope of the technical idea.

[0103] (Appendix 1) A procedure for acquiring waveform information regarding a living body, A procedure for filtering the acquired waveform information in at least one frequency band, A procedure for Hilbert-transforming the waveform information in the filtered frequency band, A procedure for calculating instantaneous values including at least any one of the instantaneous logarithmic amplitude corresponding to the absolute value of the logarithmic amplitude term of the complex wave form obtained by Hilbert-transforming the waveform information, the instantaneous frequency corresponding to the time differential value of the logarithmic phase term of the complex wave form, and the instantaneous phase corresponding to the logarithmic phase term of the complex wave form, A procedure for calculating the Gaussian distribution of the instantaneous values, A procedure for calculating the vibration wave so that the calculated Gaussian distribution becomes a predetermined Gaussian distribution, A vibration wave calculation program for causing a computer to execute. (Appendix 2) In the filtering procedure, As the frequency band, including at least any one of the bands of 0.004 to 0.015 Hz, 0.015 to 0.04 Hz, 0.04 to 0.15 Hz, 0.15 to 0.4 Hz, 0.4 to 1.5 Hz, 1.5 to 4 Hz, 4 to 15 Hz, and 15 to 40 Hz, The vibration wave calculation program described in Appendix 1. (Appendix 3) In the procedure for calculating the vibration wave, Calculating the vibration wave such that the center frequency of the theta wave band during eyes-open rest is shifted to a lower frequency side than the center frequency of the theta wave band during eyes-closed rest, Calculating the vibration wave such that the center frequency of the alpha wave band during eyes-open rest is shifted to a higher frequency side than the center frequency of the alpha wave band during eyes-closed rest The vibration wave calculation program described in Appendix 1. (Appendix 4) In the procedure for calculating the vibration wave, Based on at least any one of electroencephalogram, pulse wave, and pulse interval wave as the waveform information, calculating the vibration wave applied to the living body, The vibration wave calculation program according to any one of Appendices 1 to 3.

Explanation of Signs

[0104] 1 Physiological state control system 10 Electroencephalograph 11 Sensor 12 Main body part 20 Pulse wave meter 21 Sensor 22 Main body part 30 Driving device 31 Vibrator 32 Main body part 50 Physiological state control device 50a Control part 50b Communication part 50c Storage part 50d Interface section 51 Waveform information acquisition section 52 Filtering section 53 Conversion section 54 Instantaneous value calculation section 55 Distribution calculation section 56 Vibration wave calculation section

Claims

1. A waveform measuring device that acquires waveform information related to a living body, a physiological state control device that calculates a vibration wave to be applied to the living body based on the waveform information acquired by the waveform measuring device, and a driving device that applies the calculated vibration wave from the outside of the living body to at least any one of the left carotid artery bifurcation part, the right carotid artery bifurcation part, the vertebral artery branching from the left subclavian artery, and the vertebral artery branching from the right subclavian artery of the living body. A physiological state control system comprising the above.

2. The waveform information includes first waveform information and second waveform information, and the physiological state control device filters the acquired first waveform information and second waveform information in at least one frequency band, performs a Hilbert transform on the first waveform information and the second waveform information in the filtered frequency band, calculates instantaneous values including at least any one of the instantaneous logarithmic amplitude corresponding to the real part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the first waveform information, the instantaneous logarithmic amplitude corresponding to the real part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the second waveform information, the instantaneous frequency corresponding to the time differential value of the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the first waveform information, the instantaneous frequency corresponding to the time differential value of the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the second waveform information, and the instantaneous phase difference corresponding to the difference between the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the first waveform information and the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the second waveform information, calculates the probability density distribution of the instantaneous values in a predetermined period that can be regarded as a physiologically steady state, approximates the calculated probability density distribution as a predetermined distribution, and stores the average value and variance value of the approximated predetermined distribution as characteristic quantities of the physiological state. The physiological state control system according to Claim 1.

3. The first waveform information is a pulse wave, the second waveform information is an electroencephalogram, or the first waveform information is a pulse wave, and the second waveform information is a waveform obtained by interpolating and resampling the pulse interval data calculated from the pulse wave at a desired frequency. The physiological state control system according to Claim 2.

4. The physiological state control device includes, as the frequency band, at least any one of the bands of 0.004 to 0.015 Hz, 0.015 to 0.04 Hz, 0.04 to 0.15 Hz, 0.15 to 0.4 Hz, 0.4 to 1.5 Hz, 1.5 to 4 Hz, 4 to 8 Hz, 8 to 13 Hz, 13 to 30 Hz, and 30 to Hz. The physiological state control system according to claim 2.

5. When the probability density distribution of the instantaneous frequency becomes a multimodal distribution, the frequency band is divided into a plurality of bands so that the probability density distribution becomes unimodal. The physiological state control system according to claim 4.

6. The physiological state control device calculates the characteristic quantity of the physiological state in a physiologically normal state and a physiologically abnormal state different from the normal state, compares them to detect differences, reduces the differences between the two, and calculates the vibration wave that gradually brings the latter characteristic quantity closer to the former characteristic quantity. The physiological state control system according to claim 2.

7. Based on at least any one of electroencephalogram, pulse wave, the phase difference between electroencephalogram and pulse wave, and the phase difference between pulse wave and pulse interval waveform as the waveform information, the physiological state control device detects the difference between a physiologically normal state and a physiologically abnormal state different from the normal state. The physiological state control system according to claim 6.

8. The vibration wave is input to the driving device, and the calculated vibration wave is applied to at least any one of the left carotid artery bifurcation, the right carotid artery bifurcation, the left vertebral artery, and the right vertebral artery via the vibrator. The physiological state control system according to claim 1.

9. The physiological state control system according to claim 7, wherein when applying the vibration wave, it is monitored that the characteristic quantity is approaching the physiologically normal state.

10. In a frequency band lower than 0.4 Hz, a vibration wave obtained by performing AM modulation using a vibration wave in the range of 2 Hz to 13 Hz is input to the driving device, and the vibration wave is applied to at least any one of the left carotid artery bifurcation, the right carotid artery bifurcation, the left vertebral artery, and the right vertebral artery via the vibrator. The physiological state control system according to claim 8.

11. A step of acquiring waveform information regarding a living body; A step of calculating a vibration wave to be applied to the living body based on the acquired waveform information; A step of applying the calculated vibration wave from the outside of the living body to at least any one of the carotid artery bifurcation on the left side of the living body, the carotid artery bifurcation on the right side of the living body, the vertebral artery branching from the left subclavian artery, and the vertebral artery branching from the right subclavian artery; A physiological state control method comprising the above.

12. The step of calculating the vibration wave includes: A step of filtering the acquired waveform information in at least one frequency band; A step of performing a Hilbert transform on the filtered waveform information in the frequency band; Calculating an instantaneous value including at least any one of the instantaneous logarithmic amplitude corresponding to the real part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the waveform information, and the instantaneous frequency corresponding to the time differential value of the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the waveform information; A step of calculating the probability density distribution of the instantaneous value in a predetermined period that can be regarded as a physiologically steady state; A step of approximating the calculated probability density distribution to a Gaussian distribution; The physiological state control method according to claim 11, further comprising a step of calculating the vibration wave such that the probability density distribution becomes a predetermined Gaussian distribution.

13. The physiological state control method according to claim 12, wherein the probability density distribution is a unimodal distribution including a Gaussian distribution.

14. The step of acquiring waveform information regarding the living body includes: Acquiring a pulse wave and an electroencephalogram as the waveform information; The step of calculating the vibration wave includes: A step of filtering the acquired pulse wave, electroencephalogram, and pulse interval waveform in at least one frequency band; A step of performing a Hilbert transform on the filtered pulse wave, electroencephalogram, and pulse interval waveform in the frequency band; The instantaneous logarithmic amplitude which is the real part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the pulse wave, electroencephalogram, and pulse interval waveform, the instantaneous frequency which is the time differential value of the phase which is the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the pulse wave, electroencephalogram, and pulse interval waveform, the instantaneous phase difference corresponding to the difference between the phase which is the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the electroencephalogram and the phase which is the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the pulse wave, and the instantaneous phase difference corresponding to the difference between the phase which is the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the pulse interval waveform and the phase which is the imaginary part of the logarithm of the complex wave form obtained by performing a Hilbert transform on the pulse wave, and calculating an instantaneous value including at least any one of them. A step of calculating a probability density distribution of the instantaneous value in a predetermined period that can be regarded as a physiological steady state; A step of calculating the vibration wave so that the calculated probability density distribution becomes a predetermined distribution, The physiological state control method according to claim 12.

15. The step of acquiring waveform information regarding the living body, The pulse wave is acquired by a photoplethysmograph that measures the pulse wave flowing into the brain, The wavelength of the light used is 700 to 2000 nm, and the frequency bandwidth is in the range of 0.004 Hz to 200 Hz. The physiological state control method according to claim 12.

16. A procedure for acquiring waveform information regarding a living body, A procedure for filtering the acquired waveform information in at least one frequency band, A procedure for performing a Hilbert transform on the waveform information in the filtered frequency band, An instantaneous value including at least one of the instantaneous logarithmic amplitude corresponding to the absolute value of the logarithmic amplitude term of the complex wave form obtained by performing a Hilbert transform on the waveform information, the instantaneous frequency corresponding to the time differential value of the logarithmic phase term of the complex wave form, and the instantaneous phase corresponding to the logarithmic phase term of the complex wave form is calculated. Procedure, A procedure for calculating a Gaussian distribution of the instantaneous value, A procedure for calculating a vibration wave so that the calculated Gaussian distribution becomes the predetermined Gaussian distribution, A vibration wave calculation program that causes a computer to execute.

17. In the procedure of filtering, As the frequency band, at least one of the bands of 0.004 to 0.015 Hz, 0.015 to 0.04 Hz, 0.04 to 0.15 Hz, 0.15 to 0.4 Hz, 0.4 to 1.5 Hz, 1.5 to 4 Hz, 4 to 15 Hz, and 15 to 40 Hz is included. The vibration wave calculation program according to claim 16.

18. In the procedure of calculating the vibration wave, Calculate the vibration wave that shifts the center frequency of the θ wave band during eyes-open rest to a lower frequency side than the center frequency of the θ wave band during eyes-closed rest, Calculate the vibration wave that shifts the center frequency of the α wave band during eyes-open rest to a higher frequency side than the center frequency of the α wave band during eyes-closed rest. The vibration wave calculation program according to appended claim 16.

19. In the procedure of calculating the vibration wave, Based on at least one of electroencephalogram, pulse wave, and pulse interval wave as the waveform information, calculate the vibration wave applied to the living body. The vibration wave calculation program according to claim 16.

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