Method and device for applying electrical stimulation to the vagus nerve that reflects the degree of symptoms measured by biosignal measurement

Abstract

The present invention is a method for applying electrical stimulation to the vagus nerve via electrodes in contact with the skin of a human body, and includes a reference value setting step for measuring a user's biosignal multiple times at intervals of at least a predetermined time while no electrical stimulation is being applied and setting a reference value for the biosignal; an electrical stimulation guideline input step for inputting an electrical stimulation guideline including a numerical value for the electrical stimulation; a stimulation value adjustment step for measuring the user's biosignal and comparing the calculated value with the reference value before applying the electrical stimulation to adjust the electrical stimulation guideline; and an electrical stimulation step for applying the electrical stimulation with the adjusted value. The present invention has the advantage that the effect of electrical stimulation is further improved by applying electrical stimulation in a manner that reflects the current state of the user.

Description

[Technical field]

[0001] The present invention relates to a method and apparatus for applying electrical stimulation to the vagus nerve, and more particularly to a method and apparatus for applying electrical stimulation to the vagus nerve via electrodes in contact with the skin of the human body. [Background technology]

[0002] The vagus nerve is one of the cranial nerves and is the 10th cranial nerve. It is a mixed nerve that includes parasympathetic nerve fibers and is distributed from the brain to the face, chest, and abdomen, and is involved in regulating the parasympathetic nerves that act on the heart, lungs, digestive tract, etc. It has the longest and most complex structure of the 12 pairs of cranial nerves, and includes both sensory and motor nerve fibers.

[0003] It is known that vagus nerve stimulators for epilepsy and depression treatment have been approved by the U.S. Food and Drug Administration (FDA), and these stimulate the cervical branch located in the neck. However, this type of cervical branch electrical stimulation of the vagus nerve requires making an incision directly in the skin to expose the cervical branch of the vagus nerve, and then winding a coil, which is an electrical element, on the outside of the branch and attaching a microchip, so it cannot be used for self-treatment by the general public.

[0004] Meanwhile, in traditional Chinese medicine, a method of treating illnesses through acupuncture is applied to the ear, where the auricular branch of the vagus nerve is distributed, and it is thought to be used for stimulating treatment of the vagus nerve.

[0005] For this reason, a device has been developed that electrically stimulates the vagus nerve in the ear in order to alleviate symptoms, but it is difficult to accurately reflect the user's current condition, so it is not widely used due to the problem that it is not effective enough. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention is intended to solve the problems of the prior art described above, and its object is to provide a method and device for applying electrical stimulation to the vagus nerve that reflects the level of a user's current symptoms and has improved effectiveness. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the method of applying electrical stimulation to the vagus nerve of the present invention is a method of applying electrical stimulation to the vagus nerve via an electrode that contacts the skin of a human body, and includes a reference value setting step of measuring a user's biosignal multiple times at or above a predetermined time interval while no electrical stimulation is being applied to set a reference value for the biosignal, an electrical stimulation guideline input step of inputting an electrical stimulation guideline including a numerical value for the electrical stimulation, a stimulation value adjustment step of measuring the user's biosignal and comparing the calculated value with the reference value before applying the electrical stimulation to adjust the electrical stimulation guideline, and an electrical stimulation step of applying the electrical stimulation with the adjusted value.

[0008] In this case, the measured biological signal may be an electroencephalogram or a heart rate variability.

[0009] In the case where the biosignal of the user to be measured is an electroencephalogram, the reference value setting step includes measuring the biosignal of the user multiple times at a predetermined time interval or more, calculating the FSWR for each signal, and setting a reference value FSWR s In the stimulation value adjustment step, the FSWR calculated by measuring the user's brain waves is set. t and the FSWR s The FSWR is an index reflecting the state of the user's symptoms, and can be characterized by being calculated by dividing the power of a fast wave band having a relatively high frequency in a measured electroencephalogram by the power of a slow wave band having a relatively low frequency.

[0010] It is preferable that the fast wave band is brain waves exceeding 13 Hz, and the slow wave band is brain waves below 13 Hz.

[0011] In the reference value setting step, the FSWR s is preferably the sum of the average FSWR value calculated by measuring the electroencephalogram multiple times and the standard deviation of the FSWR value.

[0012] In the step of adjusting the stimulation value, FSWR t FSWR s It is preferable to adjust the electrical stimulation applied via the electrodes if the electrical stimulation is greater than .

[0013] FSWR t FSWR s It is preferable to increase the duty ratio of the electrical stimulation when the FSWR is larger. t and FSWR s The duty ratio of the electrical stimulation can be increased in proportion to the difference between the

[0014] In addition, in the case where the measured biosignal of the user is heart rate variability, the reference value setting step includes measuring the heart rate variability multiple times at a predetermined time interval or more, calculating an FSBR for each measurement, and setting an FSBR reference value as an FSBR. s In the stimulation value adjustment step, the FSBR calculated by measuring the user's heart rate variability is set. t and the FSBR s The FSBR is an index reflecting a state of a user with respect to symptoms, and can be characterized by being calculated by dividing the power of a high-frequency band having a relatively high frequency in the measured heart rate variability by the power of a low-frequency band having a relatively low frequency.

[0015] It is preferable that the high frequency band is in the range of 0.15 Hz to 0.4 Hz, and the low frequency band is in the range of 0.04 Hz to less than 0.15 Hz.

[0016] In the reference value setting step, the FSBR s is preferably calculated by adding the standard deviation of the FSBR values ​​to the average FSBR values ​​calculated by measuring the heart rate variability multiple times.

[0017] In the step of adjusting the stimulation value, FSBR t FSBR s It is preferable to adjust the electrical stimulation applied via the electrodes if the electrical stimulation is greater than .

[0018] FSBR t FSBR s It is preferable to increase the duty ratio of the electrical stimulation when the FSBR is larger. t and FSBR s The duty ratio of the electrical stimulation can be increased in proportion to the difference between the

[0019] Before performing the stimulation value adjustment step, an initial stimulation value setting step is performed in which an initial stimulation value is derived by adjusting a numerical value included in the electrical stimulation guideline by applying an SPI calculated by applying one or more of a demographic indicator and an environmental indicator, and the stimulation value adjustment step performs an adjustment to the initial stimulation value, and the SPI is an index that quantifies sensitivity to electrical stimulation, the demographic indicator is an indicator that statistically reflects the degree of sensitivity to electrical stimulation, and the environmental indicator is an indicator that reflects environmental factors that affect sensitivity to electrical stimulation.

[0020] The demographic indicators preferably include one or more of the following: age, sex, BMI, medication status, and disease status.

[0021] The environmental indicator preferably includes one or more of the following information: temperature, humidity, light intensity, and discomfort index.

[0022] According to another aspect of the present invention, a device for applying electrical stimulation to the vagus nerve includes electrodes that contact the skin of a human body to apply electrical stimulation, an input unit that receives an electrical stimulation guideline including numerical information for the electrical stimulation, a reference value setting unit that sets a reference value for a biosignal from a user's biosignal measured multiple times at least at a predetermined time interval when no electrical stimulation is applied, and a stimulation value adjustment unit that measures the user's biosignal before applying electrical stimulation, and compares the calculated value with the reference value to adjust the electrical stimulation guideline.

[0023] In this case, the measured biological signal may be an electroencephalogram or a heart rate variability.

[0024] When the measured biological signal is an electroencephalogram, the reference value setting unit calculates an FSWR from each piece of electroencephalogram information of the user measured a plurality of times at a predetermined time interval or more, and sets an FSWR reference value FSWR S The stimulation value adjustment unit sets the FSWR calculated by measuring the user's brain waves before applying the electrical stimulation. t and the FSWR s The electrical stimulation guideline is adjusted by comparing the FSWR with the FSWR, which is an index reflecting the state of the user's symptoms, and the FSWR can be characterized as being calculated by dividing the power of a fast wave band having a relatively high frequency in the measured electroencephalogram by the power of a slow wave band having a relatively low frequency.

[0025] It is preferable that the fast wave band is brain waves exceeding 13 Hz, and the slow wave band is brain waves below 13 Hz.

[0026] FSWR s is preferably the sum of the average FSWR value calculated by measuring the electroencephalogram multiple times and the standard deviation of the FSWR value.

[0027] The stimulus value adjusting unit is a FSWR t FSWR sIf so, it is preferable to adjust the electrical stimulation applied via the electrodes.

[0028] FSWR t FSWR s It is preferable to increase the duty ratio of the electrical stimulation when the FSWR is larger. t and FSWR s The duty ratio of the electrical stimulation can be increased in proportion to the difference between the

[0029] In addition, when the measured biological signal is heart rate variability, the reference value setting unit calculates an FSBR from each piece of heart rate variability information of the user measured multiple times at a predetermined time interval or more, and sets an FSBR reference value FSBR s The stimulation value adjusting unit sets an FSBR calculated by measuring the user's heart rate variability before applying the electrical stimulation. t and the FSBR s and adjusts the electrical stimulation guideline by comparing the FSBR with the FSBR, the FSBR being an index reflecting the state of the user with respect to the symptoms, and the FSBR may be characterized as being calculated by dividing the power of a high-frequency band having a relatively high frequency in the measured heart rate variability by the power of a low-frequency band having a relatively low frequency.

[0030] It is preferable that the high frequency band is in the range of 0.15 Hz to 0.4 Hz, and the low frequency band is in the range of 0.04 Hz to less than 0.15 Hz.

[0031] The FSBR s is preferably calculated by adding the standard deviation of the FSBR values ​​to the average FSBR values ​​calculated by measuring the heart rate variability multiple times.

[0032] The stimulus value adjusting unit is a FSBR. t FSBR s If so, it is preferable to adjust the electrical stimulation applied via the electrodes.

[0033] FSBR t FSBR sIt is preferable to increase the duty ratio of the electrical stimulation when the FSBR is larger. t and FSBR s The duty ratio of the electrical stimulation can be increased in proportion to the difference between the

[0034] The device further includes an initial stimulation value setting unit that derives an initial stimulation value by adjusting a numerical value included in an electrical stimulation guideline by applying an SPI calculated by applying one or more of a demographic indicator and an environmental indicator, the SPI being an index that quantifies sensitivity to electrical stimulation, the demographic indicator being an indicator that statistically reflects the degree of sensitivity to electrical stimulation, and the environmental indicator being an indicator that reflects environmental factors that affect the sensitivity to electrical stimulation, and the stimulation value adjustment unit can adjust the initial stimulation value derived by the initial stimulation value setting unit.

[0035] The demographic indicators preferably include one or more of the following: age, sex, BMI, medication status, and disease status.

[0036] The environmental indicator preferably includes one or more of the following information: temperature, humidity, light intensity, and discomfort index. Effect of the Invention

[0037] The present invention configured as described above has the advantage that the effect of electrical stimulation is further improved by applying electrical stimulation in a manner that reflects the current state of the user.

[0038] In addition, by applying electrical stimulation reflecting the sensitivity to electrical stimulation, it is possible to prevent the user from feeling pain due to electrical stimulation even when adjusting to the current state. [Brief description of the drawings]

[0039] [Figure 1] 1 is a flowchart illustrating a method for applying electrical stimulation to the vagus nerve that reflects the degree of symptoms based on biosignal measurement according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0040] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0041] However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to only the embodiments described below. The shapes and sizes of elements in the drawings may be exaggerated for clearer explanation, and elements represented by the same reference numerals in the drawings are the same elements.

[0042] In addition, throughout the specification, when a part is described as being "connected" to another part, this includes not only the case where the part is "directly connected" to another part, but also the case where the part is "electrically connected" to another part via another element therebetween. In addition, when a part is described as "including" or "comprising" a certain component, this means that the part can further include or comprise the other component, rather than excluding the other component, unless otherwise specified to the contrary.

[0043] In addition, terms such as "first" and "second" are used to distinguish one component from another, and should not be used to limit the scope of rights. For example, the first component can be named the second component, and similarly, the second component can be named the first component.

[0044] FIG. 1 is a flow chart for explaining a method for applying electrical stimulation to the vagus nerve reflecting the degree of symptoms based on biosignal measurement according to the present invention.

[0045] In a first embodiment of the present invention, electrical stimulation is applied to the vagus nerve in accordance with the degree of symptoms determined via electroencephalograms.

[0046] In the method of applying electrical stimulation to the vagus nerve according to the present embodiment, a reference value setting step is first performed.

[0047] The reference value is a value that serves as a reference for determining the user's current state, and in this embodiment, FSWR (Fast-to-Slow Wave Ratio) is used as an index that reflects the user's current state with respect to the symptoms. The FSWR measurement for setting the reference value is a value calculated by dividing the power of a fast wave band with a relatively high frequency by the power of a slow wave band with a relatively low frequency in an electroencephalogram measured in a state where no electrical stimulation is applied. In this case, it is preferable that the fast wave band is an electroencephalogram exceeding 13 Hz, and the slow wave band is an electroencephalogram of 13 Hz or less. Such a change in FSWR means that the user's state with respect to the symptoms changes, and the step of configuring the FSWR standard for confirming that the state has changed is the reference value setting step. Since the reference value is used to set a standard for determining the user's state, it is preferable to use multiple pieces of FSWR information, and in this case, in order to obtain information on the state at normal times rather than information on the state at a specific time, the electroencephalogram is repeatedly measured at a predetermined time interval or more, the FSWR for each is calculated, and the FSWR reference value is set as the FSWR reference value. s For example, it is preferable to use the results of repeatedly measuring the brainwaves at the same time throughout the day, particularly at the same time as the time when the electrical stimulation is to be applied, and more preferably, to calculate the FSWR for each brainwave using brainwave information measured at the same time over a week, and set the FSWR. s It is better to set FSWR. s A specific method for setting the FSWR is preferably to add the standard deviation of the FSWR to the average of the FSWR values ​​calculated by measuring the brainwaves multiple times. The reference value setting step is a process performed before applying electrical stimulation, and the reference value setting step can be repeated to set a new reference value at predetermined intervals, and it is preferable to set a new reference value at weekly intervals. sThe process of setting is performed by a reference value setting unit. The reference value setting unit may include an electroencephalogram measuring device for measuring electroencephalograms to measure FSWR and derive a reference value, and a storage device and a calculation device for storing electroencephalogram data and calculating the average and standard deviation of FSWR.

[0048] FSWR is the standard value s With this set, the electrical stimulation guideline input step is carried out.

[0049] The electrical stimulation guideline includes information on electrical stimulation for vagus nerve stimulation. The electrical stimulation guideline may be determined by a doctor's diagnosis and prescription at a hospital, or may be derived through a separate program or system. The electrical stimulation guideline for vagus nerve stimulation may include information on electrical stimulation current, frequency, duty, stimulation time, etc. Although such an electrical stimulation guideline is determined according to a user's illness or symptoms, a new electrical stimulation guideline is not received every time the electrical stimulation application device is used. Therefore, the electrical stimulation applied according to the electrical stimulation guideline may be ineffective due to the time difference between the time when the electrical stimulation guideline is received and the time when the electrical stimulation is applied. In order to solve such a problem, the present invention is characterized in that the current state of the user is evaluated based on a FSWR reference value obtained in advance through electroencephalography, and the electrical stimulation is adjusted to reflect the evaluation.

[0050] In this way, the electrical stimulation guideline including the information on the predetermined electrical stimulation is inputted through the input unit of the device for applying electrical stimulation to the vagus nerve. The method of inputting the electrical stimulation guideline may be that the information on the electrical stimulation is directly inputted by the user, or may be automatically inputted through a code (barcode or QR code) including the information on the electrical stimulation or an information storage device.

[0051] In this embodiment, an initial stimulation value setting step is performed before adjusting the electrical stimulation applied to the user to reflect the user's current state.

[0052] The initial stimulation value is a value that reflects the sensitivity to electrical stimulation and sets the electrical stimulation guideline to an appropriate range of electrical stimulation for the user. Sensitivity to electrical stimulation is a concept based on the fact that pain or discomfort from the same electrical stimulation varies from person to person, and means the degree to which pain or discomfort can be easily felt from electrical stimulation. In the present invention, sensitivity to electrical stimulation reflects not only the sensitivity according to the strength of physical stimulation and the sensitivity that a person recognizes as pain, but also the sensitivity to feel psychological and emotional discomfort or anxiety without feeling pain. If the sensitivity to electrical stimulation is high, the probability of feeling pain or discomfort from the same electrical stimulation is high, and in particular, as the current increases, greater pain or discomfort is felt.

[0053] The present invention applies the Stimulation Perception Index (SPI) as an index that quantifies the sensitivity to electrical stimulation. The SPI of the present invention is calculated by applying demographic indicators and / or environmental indicators. The demographic indicators are indicators that statistically represent the sensitivity to electrical stimulation based on biological information such as age, sex, BMI (body mass index), whether or not one is taking medication, and whether or not one has a disease. For example, children or elderly people are more sensitive to electrical stimulation than young and middle-aged people, women are more sensitive to electrical stimulation than men, and the higher the BMI, the lower the sensitivity to electrical stimulation. The demographic indicators are statistically organized information such as this information that can be applied to the SPI index. The environmental indicators are indicators that statistically represent the sensitivity to electrical stimulation based on surrounding environmental information such as temperature, humidity, illuminance, and discomfort index. For example, when the temperature or humidity is lower than a certain value, the sensitivity to electrical stimulation increases, and when the illuminance is lower, the sensitivity to electrical stimulation increases, and the discomfort index has different sensitivity to electrical stimulation depending on the range. When the sensitivity to electrical stimulation indicated by the SPI index is high, it is the case that the user is likely to feel pain or discomfort from electrical stimulation. Therefore, it is preferable to set the initial stimulation value in a direction to reduce the degree of stimulation so that the user does not feel pain or discomfort, for example, by reducing the intensity of the current. However, the electrical stimulation guideline is provided with a value that can obtain a predetermined effect, and if the intensity of the current is simply reduced, the effect of the application of the electrical stimulation may not be obtained because a sufficient stimulation is not applied. Therefore, compensation is required for the amount of current reduction, and a method of increasing the duty ratio in proportion to the reduction in current can be applied. It is preferable not to change the frequency of the electrical stimulation guideline, and since the user's discomfort increases as the time for applying the electrical stimulation increases, it is preferable to maintain the electrical stimulation application time as well. In this case, it is evaluated that the user is sensitive to electrical stimulation only when the SPI index is greater than a predetermined value, and the initial stimulation value can be set in a direction to reduce the current in proportion to the excess value and increase the duty ratio. Conversely, if the SPI index is equal to or less than a predetermined value, the current and duty ratio of the input electrical stimulation guideline can be applied as the initial stimulation value as they are.In this way, the process of deriving the initial stimulation value from the input electrical stimulation guideline is performed by the initial stimulation value setting unit, which may include a DB for deriving the SPI index, an input device for receiving input of age and gender to apply demographic indicators, and a BMI measuring device for directly measuring and applying BMI. Furthermore, it may include an input device for receiving input of information to apply environmental indicators, and may include a thermometer or hygrometer for directly measuring and reflecting temperature and humidity.

[0054] Next, a stimulation value adjustment step is performed.

[0055] The stimulation value means an electrical stimulation applied to a user through an electrode, and the present invention does not directly apply an electrical stimulation guideline or an initial stimulation value reflecting sensitivity to the electrical stimulation guideline, but adjusts the electrical stimulation guideline or the initial stimulation value to reflect the current state of the user and applies it to the user. Specifically, before applying the electrical stimulation, the FSWR calculated by measuring the user's brainwave is t is the FSWR set in the previous reference value setting step. s Compare with and adjust the electrical stimulation guideline or initial stimulation value. For example, FSWR t FSWR s If the FSWR is greater than 1, the electrical stimulation applied through the electrodes can be adjusted, and more specifically, t FSWR s If the FSWR is greater than 1, it is determined that the user's condition has worsened from the normal state, and the duty ratio of the electrical stimulation included in the electrical stimulation guideline or initial stimulation value is increased to increase the total amount of electrical stimulation applied to the user. t and FSWR sThe duty ratio of the electrical stimulation can be increased in proportion to the difference between the initial stimulation value and the reference value. The electrical stimulation guideline or the initial stimulation value is adjusted by the stimulation value adjustment unit. The stimulation value adjustment unit can include an electroencephalogram measuring device that measures electroencephalograms to calculate FSWR, and a storage device and a calculation device that store electroencephalogram data, calculate FSWR, and compare it with a reference value. Such a stimulation value adjustment unit can use all or some of the elements together with the reference value setting unit.

[0056] In addition, an electrical stimulation step is performed in which electrical stimulation with an adjusted electrical stimulation guideline or initial stimulation value is applied to the electrodes.

[0057] According to the above process, by adjusting the electrical stimulation guideline to reflect the user's sensitivity, the problem of the user feeling pain is reduced, and the effect of applying electrical stimulation is improved because the electrical stimulation guideline or the initial stimulation value is adjusted to reflect the user's current state. The electrical stimulation guideline or the initial stimulation value can be adjusted to apply to the user via a control device that controls the electrical signal applied to the electrode.

[0058] In a second embodiment of the present invention, electrical stimulation is applied to the vagus nerve in accordance with the degree of symptoms caused by heart rate variability.

[0059] In the method of applying electrical stimulation to the vagus nerve according to the present embodiment, a reference value setting step is first performed. Heart rate variability, which means the degree of variation in heart rate, means minute variations from one cardiac cycle to the next cardiac cycle. Meanwhile, pulses reflect the characteristics of heart rate, although there is a difference in the measurement position, and therefore can be used as the same as heart rate or as a substitute for heart rate. Therefore, in the following, pulse rate variability can be treated as a substitute for heart rate variability or approximately the same, and in this case, the part for measuring heart rate variability can be substituted for measuring pulse rate variability.

[0060] The reference value is a value that serves as a reference for determining the user's current state, and in this embodiment, FSBR (Fast-to-Slow Beat Ratio) is used as an index that reflects the user's current state with respect to the symptoms. The FSBR for setting the reference value is a value calculated by dividing the power of a high-frequency band with a relatively high frequency by the power of a low-frequency band with a relatively low frequency in the heart rate variability measured in a state where no electrical stimulation is applied. In this case, it is preferable that the high-frequency band is in the range of 0.15 Hz to 0.4 Hz, and the low-frequency band is in the range of 0.04 Hz to less than 0.15 Hz. Such a change in FSBR means that the user's state with respect to the symptoms changes, and the step of configuring the FSBR reference for confirming that the state has changed is the reference value setting step. Since the reference is used to set a reference for determining the user's state, it is preferable to use information on a plurality of FSBRs. In this case, in order to obtain information on the state at a normal time, rather than information on the state at a specific time, the heart rate variability is repeatedly measured at a predetermined time interval or more to calculate the FSBR for each, and the FSBR reference value FSBR is set. s For example, it is preferable to use the results of repeatedly measuring the heart rate variability at the same time of day, particularly at the same time of day when the electrical stimulation is to be applied, and more preferably, to calculate each FSBR using heart rate variability information measured at the same time of day over a week, and set the FSBRs. s A specific method for setting the standard deviation of the FSBR is preferably set to a value obtained by adding the standard deviation of the FSBR to the average of the FSBR values ​​calculated by measuring the heart rate variability multiple times. The ... sThe setting process is performed by a reference value setting unit. The reference value setting unit may include an electrocardiogram measuring device for measuring FSBR and measuring heart rate variability to derive a reference value, a storage device and a calculation device for storing electrocardiogram data and calculating the average and standard deviation of FSBR.

[0061] FSBR is the reference value s With this set, the electrical stimulation guideline input step is carried out.

[0062] The electrical stimulation guideline includes information on electrical stimulation for vagus nerve stimulation. The electrical stimulation guideline may be determined by a doctor's diagnosis and prescription at a hospital, or may be derived through a separate program or system. The electrical stimulation guideline for vagus nerve stimulation may include information such as electrical stimulation current, frequency, duty, and stimulation time. Such an electrical stimulation guideline is determined according to the user's illness or symptoms, but since a new electrical stimulation guideline is not received every time the electrical stimulation application device is used, the electrical stimulation applied according to the electrical stimulation guideline may be ineffective due to the time difference between the time when the electrical stimulation guideline is received and the time when the electrical stimulation is applied. In order to solve this problem, the present invention is characterized in that the current state of the user is evaluated based on a FSWR reference value obtained in advance through measurement of heart rate variability, and the electrical stimulation is adjusted to reflect this.

[0063] In this way, the electrical stimulation guideline including the information on the predetermined electrical stimulation is inputted through the input unit of the device for applying electrical stimulation to the vagus nerve. The method of inputting the electrical stimulation guideline may be that the information on the electrical stimulation is directly inputted by the user, or may be automatically inputted through a code (barcode or QR code) including the information on the electrical stimulation or an information storage device.

[0064] In this embodiment, an initial stimulation value setting step is performed before adjusting the electrical stimulation applied to the user to reflect the user's current state.

[0065] The initial stimulation value is a value that reflects the sensitivity to electrical stimulation and sets the electrical stimulation guideline to an appropriate range of electrical stimulation for the user. Sensitivity to electrical stimulation is a concept based on the fact that pain or discomfort from the same electrical stimulation varies from person to person, and means the degree to which pain or discomfort can be easily felt from electrical stimulation. In the present invention, sensitivity to electrical stimulation reflects not only the sensitivity according to the strength of physical stimulation and the sensitivity that a person recognizes as pain, but also the sensitivity to feel psychological and emotional discomfort or anxiety without feeling pain. If the sensitivity to electrical stimulation is high, the probability of feeling pain or discomfort from the same electrical stimulation is high, and in particular, as the current increases, greater pain or discomfort is felt.

[0066] The present invention applies the Stimulation Perception Index (SPI) as an index that quantifies the sensitivity to electrical stimulation. The SPI of the present invention is calculated by applying demographic indicators and / or environmental indicators. The demographic indicators are indicators that statistically represent the sensitivity to electrical stimulation based on biological information such as age, sex, BMI (body mass index), whether or not one is taking medication, and whether or not one has a disease. For example, children or elderly people are more sensitive to electrical stimulation than young and middle-aged people, women are more sensitive to electrical stimulation than men, and the higher the BMI, the lower the sensitivity to electrical stimulation. The demographic indicators are statistically organized information such as this information that can be applied to the SPI index. The environmental indicators are indicators that statistically represent the sensitivity to electrical stimulation based on surrounding environmental information such as temperature, humidity, illuminance, and discomfort index. For example, when the temperature or humidity is lower than a certain value, the sensitivity to electrical stimulation increases, and when the illuminance is lower, the sensitivity to electrical stimulation increases, and the discomfort index has different sensitivity to electrical stimulation depending on the range. When the sensitivity to electrical stimulation indicated by the SPI index is high, it is the case that the user is likely to feel pain or discomfort from electrical stimulation. Therefore, it is preferable to set the initial stimulation value in a direction to reduce the degree of stimulation so that the user does not feel pain or discomfort, for example, by reducing the intensity of the current. However, the electrical stimulation guideline is provided with a value that can obtain a predetermined effect, and if the intensity of the current is simply reduced, the effect of the application of the electrical stimulation may not be obtained because a sufficient stimulation is not applied. Therefore, compensation is required for the amount of current reduction, and a method of increasing the duty ratio in proportion to the reduction in current can be applied. It is preferable not to change the frequency of the electrical stimulation guideline, and since the user's discomfort increases as the time for applying the electrical stimulation increases, it is preferable to maintain the electrical stimulation application time as well. In this case, it is evaluated that the user is sensitive to electrical stimulation only when the SPI index is greater than a predetermined value, and the initial stimulation value can be set in a direction to reduce the current in proportion to the excess value and increase the duty ratio. Conversely, if the SPI index is equal to or less than a predetermined value, the current and duty ratio of the input electrical stimulation guideline can be applied as the initial stimulation value as they are.In this way, the process of deriving the initial stimulation value from the input electrical stimulation guideline is performed by the initial stimulation value setting unit, which may include a DB for deriving the SPI index, an input device for receiving input of age and gender to apply demographic indicators, and a BMI measuring device for directly measuring and applying BMI. Furthermore, it may include an input device for receiving input of information to apply environmental indicators, and may include a thermometer or hygrometer for directly measuring and reflecting temperature and humidity.

[0067] Next, a stimulation value adjustment step is performed.

[0068] The stimulation value means an electrical stimulation applied to a user through an electrode, and the present invention does not directly apply an electrical stimulation guideline or an initial stimulation value reflecting sensitivity to the electrical stimulation guideline, but adjusts the electrical stimulation guideline or the initial stimulation value to reflect the current state of the user and applies it to the user. Specifically, before applying the electrical stimulation, the FSWR calculated by measuring the heart rate variability of the user is applied. t is the FSWR set in the previous reference value setting step. s Compare with and adjust the electrical stimulation guideline or initial stimulation value. For example, FSWR t FSWR s If the FSWR is greater than 1, the electrical stimulation applied through the electrodes can be adjusted, and more specifically, t FSWR s If the FSWR is greater than 1, the user's condition is evaluated as being worse than the normal condition, and the duty ratio of the electrical stimulation included in the electrical stimulation guideline or initial stimulation value is increased to increase the total amount of electrical stimulation applied to the user. t and FSWR sThe duty ratio of the electrical stimulation can be increased in proportion to the difference between the initial stimulation value and the reference value. The electrical stimulation guideline or the initial stimulation value is adjusted by the stimulation value adjustment unit. The stimulation value adjustment unit can include an electrocardiogram measuring device that measures heart rate variability to calculate FSWR, and a storage device and a calculation device that store electrocardiogram data, calculate FSWR, and compare it with a reference value. Such a stimulation value adjustment unit can use all or some of the elements together with the reference value setting unit.

[0069] In addition, an electrical stimulation step is performed in which electrical stimulation with an adjusted electrical stimulation guideline or initial stimulation value is applied to the electrodes.

[0070] According to the above process, by adjusting the electrical stimulation guideline to reflect the user's sensitivity, the problem of the user feeling pain is reduced, and the effect of applying electrical stimulation is improved because the electrical stimulation guideline or the initial stimulation value is adjusted to reflect the user's current state. The electrical stimulation guideline or the initial stimulation value can be adjusted to apply to the user via a control device that controls the electrical signal applied to the electrode.

[0071] Although the present invention has been described above through preferred embodiments, the above-mentioned embodiments are merely illustrative of the technical idea of ​​the present invention, and it will be understood by those of ordinary skill in the art that various changes are possible within the scope of the technical idea of ​​the present invention. Therefore, the scope of protection of the present invention should be interpreted not by specific embodiments but by the matters described in the claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

Claims

1. 1. A method for applying electrical stimulation to the vagus nerve via an electrode in contact with the skin of a human body, comprising: a reference value setting step of measuring the user's biosignal multiple times at a predetermined time interval or more in a state where no electrical stimulation is applied, and setting a reference value for the biosignal; An electrical stimulation guideline input step of inputting an electrical stimulation guideline including a numerical value for the electrical stimulation; A stimulation value adjustment step of adjusting an electrical stimulation guideline by measuring a biosignal of the user and comparing the calculated value with the reference value before applying the electrical stimulation; and applying the electrical stimulation at the adjusted value.

2. 2. The method for applying electrical stimulation to the vagus nerve according to claim 1, wherein the measured biosignal of the user is an electroencephalogram or a heart rate variability.

3. The biosignal of the user to be measured is an electroencephalogram; In the reference value setting step, measurements are made multiple times at intervals of a predetermined time or more, an FSWR is calculated for each measurement, and an FSWR reference value FSWR s Set In the stimulation value adjustment step, the FSWR calculated by measuring the user's brain waves is t and the FSWR s Compare with 3. The method of claim 2, wherein the FSWR is an index reflecting a state of the user's symptoms and is calculated by dividing the power of a fast wave band having a relatively high frequency in a measured electroencephalogram by the power of a slow wave band having a relatively low frequency.

4. 4. The method of claim 3, wherein the fast wave band is a brain wave exceeding 13 Hz, and the slow wave band is a brain wave below 13 Hz.

5. In the reference value setting step, The FSWR s 4. The method for applying electrical stimulation to the vagus nerve according to claim 3, wherein the FSWR value is calculated by measuring electroencephalograms multiple times and adding the standard deviation of the FSWR values ​​to the average of the FSWR values.

6. In the stimulation value adjustment step, F.S.W.R. t is FSWR s 4. The method of claim 3, further comprising adjusting the electrical stimulation applied via the electrodes if the electrical stimulation is greater than .

7. F.S.W.R. t is FSWR s 7. The method for applying electrical stimulation to the vagus nerve according to claim 6, further comprising increasing a duty ratio of the electrical stimulation when the electrical stimulation is greater than the predetermined value.

8. F.S.W.R. t and FSWR s 8. The method for applying electrical stimulation to the vagus nerve according to claim 7, further comprising increasing a duty ratio of the electrical stimulation in proportion to a difference between the

9. the measured biosignal of the user is heart rate variability; In the reference value setting step, the FSBR is measured multiple times at a predetermined time interval or more, and the FSBR for each measurement is calculated, and the FSBR reference value FSBR s Set In the stimulation value adjustment step, the FSBR calculated by measuring the user's heart rate variability is t and the above FSBR s Compare with 3. The method of claim 2, wherein the FSBR is an index reflecting a user's condition with respect to symptoms, and is calculated by dividing the power of a high-frequency band having a relatively high frequency in the measured heart rate variability by the power of a low-frequency band having a relatively low frequency.

10. 10. The method for applying electrical stimulation to the vagus nerve according to claim 9, wherein the high frequency band is in the range of 0.15 Hz or more and 0.4 Hz or less, and the low frequency band is in the range of 0.04 Hz or more and less than 0.15 Hz.

11. In the reference value setting step, The FSBR s 10. The method for applying electrical stimulation to the vagus nerve according to claim 9, wherein the FSBR value is calculated by measuring the heart rate variability multiple times and adding the standard deviation of the FSBR value to the average of the FSBR values.

12. In the stimulation value adjustment step, FSB R t is FSBR s 10. The method for applying electrical stimulation to the vagus nerve according to claim 9, further comprising adjusting the electrical stimulation applied via the electrodes if the electrical stimulation is greater than the threshold.

13. FSB R t is FSBR s The method for applying electrical stimulation to the vagus nerve according to claim 12, further comprising increasing a duty ratio of the electrical stimulation when the electrical stimulation is greater than the predetermined value.

14. FSB R t and FSBR s 14. The method for applying electrical stimulation to the vagus nerve according to claim 13, further comprising increasing a duty ratio of the electrical stimulation in proportion to a difference between the

15. Before performing the stimulation value adjustment step, an initial stimulation value setting step is performed to derive an initial stimulation value by adjusting a numerical value included in an electrical stimulation guideline by applying an SPI calculated by applying one or more of a demographic indicator and an environmental indicator; The stimulus value adjustment step performs an adjustment to an initial stimulus value, The SPI is an index that quantifies sensitivity to electrical stimulation, Demographic indicators are indicators that statistically reflect the degree of sensitivity to electrical stimulation.

2. The method for applying electrical stimulation to the vagus nerve according to claim 1, wherein the environmental marker is a marker that reflects an environmental factor that affects sensitivity to electrical stimulation.

16. The method of claim 15, wherein the demographic indicators include one or more of the following information: age, sex, BMI, whether or not the patient is taking medication, and whether or not the patient has a disease.

17. The method of claim 15, wherein the environmental indicator includes one or more of the following information: temperature, humidity, illuminance, and discomfort index.

18. An electrode that contacts the skin of a human body to apply electrical stimulation; an input unit for receiving an input of an electrical stimulation guideline including numerical information for the electrical stimulation; a reference value setting unit that sets a reference value for the biosignal from the biosignal of the user that is measured multiple times at a predetermined time interval or more in a state in which no electrical stimulation is applied; A device for applying electrical stimulation to the vagus nerve, comprising: a stimulation value adjustment unit that adjusts an electrical stimulation guideline by measuring a user's biological signal and comparing the calculated value with the reference value before applying electrical stimulation.

19. 19. The device for applying electrical stimulation to the vagus nerve according to claim 18, wherein the biological signal to be measured is an electroencephalogram or a heart rate variability.

20. The biosignal being measured is an electroencephalogram, The reference value setting unit calculates an FSWR from each of the user's electroencephalogram information measured a plurality of times at a predetermined time interval or more, and sets an FSWR reference value FSWR s Set The stimulation value adjusting unit is configured to adjust the stimulation value based on the FSWR calculated by measuring the user's brain waves before applying the electrical stimulation. t and the FSWR s Compare and adjust the electrical stimulation guidelines.

20. The device for applying electrical stimulation to the vagus nerve of claim 19, wherein the FSWR is an index reflecting a state of a user's symptoms, and the FSWR is calculated by dividing the power of a fast wave band having a relatively high frequency in a measured electroencephalogram by the power of a slow wave band having a relatively low frequency.

21. 21. The device for applying electrical stimulation to the vagus nerve according to claim 20, wherein the fast wave band is an electroencephalogram exceeding 13 Hz, and the slow wave band is an electroencephalogram below 13 Hz.

22. The FSWR s 21. The device for applying electrical stimulation to the vagus nerve as described in claim 20, wherein the FSWR value is obtained by adding the standard deviation of the FSWR value to an average FSWR value calculated by measuring electroencephalograms multiple times.

23. The stimulation value adjustment unit is F.S.W.R. t is FSWR s The device for applying electrical stimulation to the vagus nerve as described in claim 20, characterized in that if the electrical stimulation is greater than the predetermined value, the electrical stimulation applied via the electrodes is adjusted.

24. F.S.W.R. t is FSWR s 24. The device for applying electrical stimulation to the vagus nerve as described in claim 23, characterized in that when the electrical stimulation is greater than the electrical stimulation voltage, a duty ratio of the electrical stimulation is increased.

25. F.S.W.R. t and FSWR s 25. The device for applying electrical stimulation to the vagus nerve according to claim 24, wherein a duty ratio of the electrical stimulation is increased in proportion to a difference between

26. the biosignal being measured is heart rate variability; the reference value setting unit calculates an FSBR from each of the user's heart rate variability information measured a plurality of times at least at a predetermined time interval, and sets an FSBRs that is an FSBR reference value; The stimulation value adjusting unit is configured to adjust the stimulation value based on the FSBR calculated by measuring the heart rate variability of the user before applying the electrical stimulation. t and the above FSBR s The electrical stimulation guidelines are adjusted based on the comparison.

20. The device for applying electrical stimulation to the vagus nerve of claim 19, wherein the FSBR is an index reflecting a state of the user with respect to symptoms, and the FSBR is calculated by dividing the power of a high-frequency band having a relatively high frequency in the measured heart rate variability by the power of a low-frequency band having a relatively low frequency.

27. 27. The device for applying electrical stimulation to the vagus nerve according to claim 26, wherein the high frequency band is in the range of 0.15 Hz or more and 0.4 Hz or less, and the low frequency band is in the range of 0.04 Hz or more and less than 0.15 Hz.

28. The FSBR s 27. The device for applying electrical stimulation to the vagus nerve according to claim 26, wherein the FSBR value is calculated by measuring the heart rate variability multiple times and adding the standard deviation of the FSBR value to the average of the FSBR values.

29. The stimulation value adjustment unit is FSB R t is FSBR s 27. The device for applying electrical stimulation to the vagus nerve as described in claim 26, characterized in that if the electrical stimulation applied via the electrodes is greater, the electrical stimulation is adjusted.

30. FSB R t is FSBR s 30. The device for applying electrical stimulation to the vagus nerve as described in claim 29, characterized in that when the abscissa is greater than the ordinate, a duty ratio of the electrical stimulation is increased.

31. FSB R t and FSBR s 31. The device for applying electrical stimulation to the vagus nerve according to claim 30, wherein the duty ratio of the electrical stimulation is increased in proportion to the difference between

32. The method further includes an initial stimulation value setting unit that derives an initial stimulation value by adjusting a numerical value included in the electrical stimulation guideline by applying the SPI calculated by applying one or more of a demographic indicator and an environmental indicator, The SPI is an index that quantifies sensitivity to electrical stimulation, the demographic indicator is an indicator that statistically reflects the degree of sensitivity to electrical stimulation, and the environmental indicator is an indicator that reflects environmental factors that affect the sensitivity to electrical stimulation. The device for applying electrical stimulation to the vagus nerve according to claim 18 , wherein the stimulation value adjusting unit adjusts the initial stimulation value derived by the initial stimulation value setting unit.

33. The device for applying electrical stimulation to the vagus nerve according to claim 32, wherein the demographic indicators include one or more of the following information: age, sex, BMI, whether or not the patient is taking medication, and whether or not the patient has a disease.

34. 33. The device for applying electrical stimulation to the vagus nerve according to claim 32, wherein the environmental indicator includes one or more pieces of information of temperature, humidity, illuminance, and discomfort index.

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