A transcranial magnetic stimulation system and a stimulation method thereof

Abstract

The present invention belongs to the technical field of transcranial magnetic stimulation methods and devices, and specifically relates to a transcranial magnetic stimulation system and a stimulation method thereof, including pre-stimulation, prediction of neuronal action potentials and formal stimulation. EEG signals are acquired in advance through trial stimulation, and the neuronal action potential thresholds of the EEG signals during the trial stimulation are calculated and analyzed to obtain the action potential threshold transfer probability, so that the neuronal action potential threshold can be predicted during formal stimulation and the stimulation intensity can be controlled to ensure that the neuronal action potential threshold during each magnetic stimulation can reach the required value. The method provided in the present application can provide a suitable magnetic stimulation intensity in real time according to the adaptability of each patient's state, avoid excessively high or low neuronal action potentials, and thus obtain better therapeutic effects while ensuring the safety of the magnetic stimulation process.

Description

Technical Field

[0001] The present invention belongs to the technical field of transcranial magnetic stimulation methods and devices, and specifically relates to a transcranial magnetic stimulation system and a stimulation method thereof. Background Art

[0002] With the continuous development of brain science, the biological effects of electromagnetic fields are increasingly used in the treatment of brain diseases such as insomnia, depression, and epilepsy. Magnetic stimulation of specific intensity and frequency on specific parts of the human brain can cause changes in the action potential of neurons in the corresponding functional areas, thereby affecting neural electrical activity and having a certain therapeutic effect.

[0003] The action potential threshold of neurons in the brain will change as magnetic stimulation is carried out. Therefore, using magnetic stimulation of a fixed intensity during treatment cannot achieve the desired treatment goal. During transcranial magnetic stimulation treatment, if the intensity of magnetic stimulation is higher than a certain threshold, it will cause harm to the human brain. If the intensity of magnetic stimulation is lower than a certain threshold, the therapeutic effect cannot be achieved. In the prior art, magnetic intervention is generally performed using a preset variable intensity magnetic stimulation. However, the specific brain state of each patient is different, and the preset magnetic stimulation intensity often cannot achieve a good therapeutic effect. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defect in the prior art that the stimulation intensity of the transcranial magnetic stimulation system is difficult to determine, thereby affecting the treatment effect, thereby providing a transcranial magnetic stimulation system and a stimulation method thereof.

[0005] A transcranial magnetic stimulation method comprises the following steps:

[0006] Step S1: using magnetic pulses of fixed frequency and intensity to perform transcranial test stimulation, and collecting EEG signals during the test stimulation process;

[0007] Step S2: discretizing the neuron action potential threshold of the EEG signal during the trial stimulation, and calculating the action potential threshold transition probability;

[0008] Step S3: Control the intensity of magnetic stimulation during formal transcranial stimulation according to the action potential transfer probability.

[0009] Furthermore, in the step S1, when the transcranial trial stimulation is performed, the magnetic pulses include two groups, each group of the magnetic pulses includes 300 pulses, the pulse frequency is 1 Hz, the stimulation intensity is 1.5 T, and the interval between the two groups of magnetic pulses is three minutes.

[0010] Furthermore, the step S2 includes the following steps:

[0011] Step S2.1: Using a fixed time length as the Markov step length, the nearest neighbor method is used to discretize the neuronal action potential threshold of the EEG signal during the trial stimulation process;

[0012] Step S2.2: Calculate the transition probability from one action potential threshold to another action potential threshold;

[0013] Step S2.3: Calculate the state transition probability matrix of all discretized action potential thresholds.

[0014] Furthermore, in step S2.1, the neuron action potential threshold of the EEG signal during the trial stimulation is discretized using the nearest neighbor method with 2S as a Markov step length, so that ,in is the discretized action potential threshold, is the preset action potential threshold.

[0015] Furthermore, in step S2.1, the preset action potential threshold is , four hundred action potential thresholds are distributed from -60mV to -20mV at intervals of 0.1mV.

[0016] Further, in step S2.2, according to Find the action potential threshold transition probability ,in Indicates the action potential threshold of the neuron during the trial stimulation The number of transformations, Indicates that the action potential threshold of the neuron during the trial stimulation is Transformed into The number of times.

[0017] Furthermore, in step S2.3, the state transition probability matrix of the discretized action potential threshold is ,in The action potential threshold of the neuron during the test stimulation is Transformed into probability.

[0018] Furthermore, in step S3, the method of controlling the intensity of magnetic stimulation during formal transcranial stimulation according to the action potential transition probability is to control the stimulation coil current according to the LIF membrane voltage dynamic equation and the state transition probability matrix.

[0019] Furthermore, in the step S3, during the formal transcranial stimulation, the magnetic pulses include two groups, each group of the magnetic pulses includes three hundred pulses, the pulse frequency is 1 Hz, and the interval between the two groups of magnetic pulses is three minutes.

[0020] A transcranial magnetic stimulation system controls transcranial magnetic stimulation by the above-mentioned transcranial magnetic stimulation method; the transcranial magnetic stimulation system comprises a control module, a signal acquisition module and a stimulation module; the signal acquisition module is used to collect brain electrical signals; the control module is used to control the stimulation module to perform transcranial magnetic stimulation.

[0021] Beneficial effects: The present invention discloses a transcranial magnetic stimulation system and a stimulation method thereof. EEG signals are acquired in advance through trial stimulation, and the neuronal action potential threshold of the EEG signals during the trial stimulation is calculated and analyzed to obtain the action potential threshold transfer probability, thereby being able to predict the neuronal action potential threshold during formal stimulation and control the stimulation intensity, ensuring that the neuronal action potential threshold during each magnetic stimulation can reach the required value; the method provided in the present application can provide appropriate magnetic stimulation intensity in real time according to the adaptability of each patient's state, avoiding excessive or low neuronal action potential, thereby obtaining better therapeutic effects while ensuring the safety of the magnetic stimulation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 is a system structure block diagram of the present invention;

[0024] Figure 2 It is a schematic diagram of the method steps of the present invention. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0026] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0027] Embodiment 1:

[0028] Reference Figure 2 As shown, this embodiment provides a transcranial magnetic stimulation method, comprising the following steps:

[0029] Step S1: using magnetic pulses of fixed frequency and intensity to perform transcranial test stimulation, and collecting EEG signals during the test stimulation process;

[0030] In the step S1, when the transcranial trial stimulation is performed, the magnetic pulses include two groups, each group of the magnetic pulses includes 300 pulses, the pulse frequency is 1 Hz, the stimulation intensity is 1.5 T, and the interval between the two groups of magnetic pulses is three minutes.

[0031] Step S2: discretizing the neuron action potential threshold of the EEG signal during the trial stimulation, and calculating the action potential threshold transition probability;

[0032] The step S2 comprises the following steps:

[0033] Step S2.1: Using a fixed time length as the Markov step length, the nearest neighbor method is used to discretize the neuronal action potential threshold of the EEG signal during the trial stimulation process;

[0034] In step S2.1, the neuron action potential threshold of the EEG signal during the test stimulation is discretized using the nearest neighbor method with 2S as a Markov step length. ,in is the discretized action potential threshold, is the preset action potential threshold.

[0035] As a preferred embodiment of this invention, in step S2.1, the preset action potential threshold is , four hundred action potential thresholds are distributed from -60mV to -20mV at intervals of 0.1mV. Specifically, the preset action potential thresholds are divided into -59.9mV, -59.8mV, -59.7mV, ..., -20.1mV, -20mV. When the action potential threshold of the test stimulus is between two preset values, the larger value is taken.

[0036] Step S2.2: Calculate the transition probability from one action potential threshold to another action potential threshold;

[0037] In step S2.2, according to Find the action potential threshold transition probability ,in Indicates the action potential threshold of the neuron during the trial stimulation The number of transformations, Indicates that the action potential threshold of the neuron during the trial stimulation is Transformed into The number of times.

[0038] Step S2.3: Calculate the state transition probability matrix of all discretized action potential thresholds.

[0039] In step S2.3, the state transition probability matrix of the discretized action potential threshold is: ,in The action potential threshold of the neuron during the test stimulation is Transformed into probability.

[0040] Step S3: Control the intensity of magnetic stimulation during formal transcranial stimulation according to the action potential transfer probability.

[0041] In the step S3, the intensity of magnetic stimulation during the formal transcranial stimulation is controlled according to the action potential transition probability.

[0042] Specifically, according to the state transition probability matrix, we get ,in The action potential threshold of the neuron at time t is The probability of .

[0043] Thus we get .

[0044] When the stimulation coil parameters and neuron parameters are determined, there is a corresponding relationship between the current flowing through the stimulation coil and the neuron potential. Based on this relationship, the stimulation coil current can be controlled to make the neuron potential reach a preset value.

[0045] Specifically, according to the LIF (Leaky integrate and fire) model,

[0046] The dynamic equation of LIF membrane voltage is: , ,

[0047] So the neuronal potential ,

[0048] in, is the neuron input resistance, is the equivalent input current, is the neuron capacitance, is the neuronal membrane time constant.

[0049] In this embodiment, the induced electric field generated by the electromagnetic coil is: ,

[0050] in, is the vacuum permeability, is the distance from the coil element to the fixed point in space, is the coil element, is the electrical conductivity of brain tissue, and A is the neuron area.

[0051] We can get: ,

[0052] and ,

[0053] Here The stimulation coil current needs to be controlled.

[0054] As a preferred embodiment of this embodiment, in step S3, during the formal transcranial stimulation, the magnetic pulses include two groups, each group of magnetic pulses includes 300 pulses, the pulse frequency is 1 Hz, and the interval between the two groups of magnetic pulses is three minutes. The frequency and duration are consistent with those during the trial stimulation, which can ensure the accuracy of the prediction to the greatest extent.

[0055] The present embodiment provides a transcranial magnetic stimulation system and a stimulation method thereof, which obtains EEG signals in advance through trial stimulation, calculates and analyzes the neuronal action potential thresholds of the EEG signals during the trial stimulation, and obtains the action potential threshold transfer probability, so that the neuronal action potential threshold can be predicted during formal stimulation and the stimulation intensity can be controlled to ensure that the neuronal action potential threshold during each magnetic stimulation reaches the required value; the method provided in the present application can provide appropriate magnetic stimulation intensity in real time according to the adaptability of each patient's state, avoid excessively high or low neuronal action potentials, and thus obtain better therapeutic effects while ensuring the safety of the magnetic stimulation process.

[0056] Embodiment 2:

[0057] Reference Figure 1 As shown, this embodiment provides a transcranial magnetic stimulation system, which controls transcranial magnetic stimulation through the above-mentioned transcranial magnetic stimulation method; the transcranial magnetic stimulation system includes a control module, a signal acquisition module and a stimulation module; the signal acquisition module is used to collect EEG signals; the control module is used to control the stimulation module to perform transcranial magnetic stimulation.

[0058] Specifically, the transcranial magnetic stimulation system includes a human-computer interaction module, a first control module, a safety detection module, a power module, a signal acquisition module, a stimulation module, a second control module and a cooling module; the control module includes a first control module and a second control module;

[0059] The first control module is connected to the human-computer interaction module, the safety detection module, the signal acquisition module and the stimulation module respectively; the human-computer interaction module is used for personnel to input control instructions and output and display system status; the safety detection module is connected to the power supply module, and is used to obtain the output current of the current module and feed it back to the first control module. When the current signal is abnormal, the first control module issues a power-off instruction; the signal acquisition module is connected to the stimulation module, and is used to collect EEG signals and feed them back to the first control module and the second control module; the stimulation module is used to implement the stimulation function under the control of the first control module.

[0060] The system also includes a cooling module, which is connected to the stimulation module and is used to cool the stimulation module. The power supply module provides power supply for the system. The second control module is used to receive EEG signals, calculate and analyze and control the intensity of magnetic stimulation.

[0061] The stimulation module includes an electrical stimulation module, a magnetic stimulation module and a physical stimulation module, so that the system can achieve multi-mode stimulation, including a single electrical stimulation mode, a single magnetic stimulation mode, a single physical stimulation mode, and a parallel stimulation mode of electrical and physical stimulation.

[0062] In the single electrical stimulation mode, the first control module controls the electrical stimulation module to operate.

[0063] In the single magnetic stimulation mode, the first control module controls the magnetic stimulation module to work. The system completes the stimulation work according to the method steps in the first embodiment, and controls the intensity of the magnetic stimulation through the second control module.

[0064] In the single physical stimulation mode, the first control module controls the physical stimulation module to operate.

[0065] In the electrical stimulation and physical stimulation parallel stimulation mode, the first control module controls the electrical stimulation module and the physical stimulation module to work.

[0066] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A transcranial magnetic stimulation system, characterized in that: The transcranial magnetic stimulation system includes a control module, a signal acquisition module and a stimulation module; the signal acquisition module is used to collect EEG signals; the control module is used to control the stimulation module to perform transcranial magnetic stimulation; The transcranial magnetic stimulation system is used to control transcranial magnetic stimulation by the following method: Step S1: using magnetic pulses of fixed frequency and intensity to perform transcranial trial stimulation, and collecting EEG signals during the trial stimulation process; Step S2: discretizing the neuron action potential threshold of the EEG signal during the trial stimulation, and calculating the action potential threshold transition probability; Step S3: controlling the intensity of magnetic stimulation during formal transcranial stimulation according to the action potential transfer probability; The step S2 comprises the following steps: Step S2.1: Using a fixed time length as the Markov step length, the nearest neighbor method is used to discretize the neuronal action potential threshold of the EEG signal during the trial stimulation process; Step S2.2: Calculate the transition probability from one action potential threshold to another action potential threshold; Step S2.3: Calculate the state transition probability matrix of all discretized action potential thresholds; In step S2.1, the neuron action potential threshold of the EEG signal during the test stimulation is discretized using the nearest neighbor method with 2S as a Markov step length. ,in is the discretized action potential threshold, is the preset action potential threshold; In step S2.2, according to Find the action potential threshold transition probability ,in Indicates the action potential threshold of the neuron during the trial stimulation The number of transformations, Indicates that the action potential threshold of the neuron during the trial stimulation is Transformed into The number of times.

2. A transcranial magnetic stimulation system according to claim 1, characterized in that: In the step S1, when the transcranial trial stimulation is performed, the magnetic pulses include two groups, each group of the magnetic pulses includes 300 pulses, the pulse frequency is 1 Hz, the stimulation intensity is 1.5 T, and the interval between the two groups of magnetic pulses is three minutes.

3. A transcranial magnetic stimulation system according to claim 1, characterized in that: In step S2.1, the preset action potential threshold is , four hundred action potential thresholds are distributed from -60mV to -20mV at intervals of 0.1mV.

4. A transcranial magnetic stimulation system according to claim 1, characterized in that: In step S2.3, the state transition probability matrix of the discretized action potential threshold is: ,in The action potential threshold of the neuron during the test stimulation is Transformed into probability.

5. A transcranial magnetic stimulation system according to claim 1, characterized in that: In step S3, the method for controlling the intensity of magnetic stimulation during formal transcranial stimulation according to the action potential transition probability is to control the stimulation coil current according to the LIF membrane voltage dynamic equation and the state transition probability matrix.

6. A transcranial magnetic stimulation system according to claim 1, characterized in that: In the step S3, during the formal transcranial stimulation, the magnetic pulses include two groups, each group of magnetic pulses includes 300 pulses, the pulse frequency is 1 Hz, and the interval between the two groups of magnetic pulses is three minutes.

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