Stimulation system, implant device, control device, control method for control device, and program

Abstract

The present invention has an implant device 10 that is embedded in the body of an animal subject including a human and that is communicably connected to a control device 20 that is disposed outside the body of said subject. The implant device 10 is for detecting an electrical signal as a physiological signal at a prescribed site within the subject's body, transmitting detection information that indicates temporal changes of said electrical signal, receiving, from the control device 20, a stimulus instruction indicative of a stimulus to be applied to the subject's body, and applying an electrical stimulus to the prescribed site within the subject's body in accordance with said stimulus instruction.

Description

[Technical Field]

[0001] The present invention relates to a stimulation system, an implant device, a control device, a control method for a control device, and a program. [Background technology]

[0002] Patent Document 1 discloses a neural implant device that includes a circuit configured to receive an input signal and generate an electrical signal based on the received input signal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2019-503809 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional neural implant devices described above have the problem that, because they are not controlled based on physiological signals within the body, they do not necessarily provide stimulation that is appropriate for the subject's condition.

[0005] The present invention has been made in consideration of the above-mentioned situation, and one of its objects is to provide a stimulation system, an implant device, a control device, a control method for a control device, and a program that can provide stimulation according to the condition of a subject. [Means for solving the problem]

[0006] One aspect of the present invention for solving the problems of the above-mentioned conventional examples is an implant device that is implanted in a subject body, which is an animal including a human, and is communicatively connected to a control device located outside the subject body, and that has: detection means for detecting an electrical signal as a physiological signal at a predetermined site within the subject body; transmission / reception means for sending detection information representing a change over time in the detected electrical signal and receiving, from the control device, a stimulation instruction representing a stimulation to be applied to the subject body; and application means for applying an electrical stimulation to the predetermined site within the subject body based on the stimulation instruction received by the transmission / reception means.

[0007] Another aspect of the present invention for solving the problems of the above-mentioned conventional examples is a control device placed outside a subject body which is an animal including a human, and communicatively connected to an implant device, the implant device being implanted in the subject body and detecting an electrical signal as a physiological signal at a predetermined site within the subject body, the control device including: receiving means for receiving detection information indicating the detection result of the electrical signal transmitted by the implant device; determining means for determining the content of the stimulation to be applied to the subject body by the implant device based on the received detection information; and transmitting means for transmitting a stimulation instruction indicating the determined stimulation to the implant device. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a stimulus that is appropriate for the subject's situation. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram illustrating an example of a stimulus providing system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a functional block diagram illustrating an example of a control device according to an embodiment of the present invention. [Figure 3] FIG. 2 is a flowchart illustrating an example of the operation of the stimulus providing system according to the embodiment of the present invention. [Figure 4] FIG. 4 is a functional block diagram illustrating another example of a control device according to an embodiment of the present invention. [Figure 5] 10A and 10B are explanatory diagrams illustrating an example of frequency domain information of detection information detected by the stimulus providing system according to the embodiment of the present invention. [Figure 6] 3 is an explanatory diagram illustrating an example of stimulus setting information used by the stimulus providing system according to the embodiment of the present invention. FIG. [Figure 7] 3A and 3B are explanatory diagrams illustrating examples of signals processed by a stimulus system according to an embodiment of the present invention. [Figure 8] FIG. 4 is another explanatory diagram illustrating an example of a signal processed by a stimulus delivery system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment of the present invention will be described with reference to the drawings. As shown in Fig. 1, a stimulation system 1 according to the embodiment of the present invention includes an implant device 10 that is implanted in a subject body, which is an animal including a human, and a control device 20 that is disposed outside the subject body.

[0011] Here, the implant device 10 includes a transmitter / receiver 11, a power supply unit 12, a stimulation circuit unit 13, a sensor unit 14, and a processor unit 15. The control device 20 includes a transmitter / receiver 21, a control unit 22, a memory unit 23, a communication unit 24, and a power supply unit 25.

[0012] The transmitter / receiver 11 of the implant device 10 transmits data to the control device 20 disposed outside the subject in response to an instruction input from the processor unit 15. The transmitter / receiver 11 also receives data from the control device 20 and outputs the data to the processor unit 15. The data can be transmitted and received using a well-known transmission / reception method such as NFC, Wi-Fi, Bluetooth (registered trademark), or RFID wireless communication standards. Furthermore, in one example of the present embodiment, the transmitter / receiver 11 may receive power wirelessly from the control device 20 and output the power thus received to the power supply unit 12.

[0013] The power supply unit 12 includes a battery B and supplies power to each component of the implant device 10. In one example of the present embodiment, the battery B included in the power supply unit 12 is a secondary battery, and may receive power input from the transmitter / receiver 11 to charge the battery B.

[0014] Under the control of the processor 15, the stimulation circuit unit 13 applies stimulation to the subject via electrodes arranged at predetermined locations within the subject's body (hereinafter referred to as stimulation locations). The stimulation locations where the electrodes are arranged are locations that can stimulate nerves, etc., used in spinal cord stimulation therapy, sacral nerve stimulation therapy, vagus nerve stimulation therapy, deep brain stimulation therapy, etc., and are selected depending on the type of stimulation to be applied to the subject. The arrangement of the electrodes in the stimulation circuit unit 13 can be any of the widely known arrangements used in the various stimulation therapies described above, so a detailed description will be omitted here. The stimulation may be, for example, a periodic electrical signal or a single pulse signal, and its amplitude, frequency, duration, pulse width, etc. are controlled by the processor 15, which will be described later.

[0015] The sensor unit 14 detects an electrical signal representing a physiological signal of the subject (for example, a signal representing the physiological signal of the subject at the detection site as a magnitude of its potential) using electrodes placed at a predetermined site within the subject's body (hereinafter referred to as the detection site). Here, the physiological signal is a signal that serves as a biomarker, such as a membrane potential, nerve action potential, organ pressure, tissue impedance, temperature, or other signal within the subject's body, and may be selected according to predetermined rules depending on the type of stimulation to be applied. Furthermore, the stimulation site and the detection site may be different sites, adjacent (relatively close) sites, or the same site.

[0016] The processor unit 15 is configured to include a program control device such as a CPU and a storage device such as a memory, and transmits detection information representing the electrical signal detected by the sensor unit 14 (for example, if the electrical signal represents a physiological signal of the subject at the detection site by the magnitude of its potential, the information represents the magnitude of the potential) to the control device 20 via the transmitter-receiver unit 11. The processor unit 15 may transmit the detection information representing the detected electrical signal each time it detects the electrical signal, or may store and hold information representing electrical signals detected multiple times in a memory or the like, and then transmit the detection information representing the information stored in the memory to the control device 20 via the transmitter-receiver unit 11 at a predetermined transmission timing thereafter.

[0017] That is, the detection information may include, for example, information representing an electrical signal that is the result of one detection, or may include information representing a plurality of electrical signals that are the result of multiple detections (detection information that represents a change over time in the detected electrical signals). When information representing electrical signals that are the result of multiple detections is included, the processor unit 15 may convert the detected electrical signals into frequency domain information, which is later performed by the control device 20, into the frequency domain information. n Information representing electrical signals resulting from detections performed a number of times (n is a natural number of 1 or more) may be included in the detection information.

[0018] In this case, the processor unit 15 n The sensor unit 14 repeatedly obtains an electrical signal representing a physiological signal at a predetermined site in the subject's body at predetermined timings over a period of two times (n is a natural number of 1 or more), and stores information representing the electrical signal as the detection result. n The detection results of the electrical signal for each batch are sent to the control device 20 as detection information representing the change in the electrical signal over time.

[0019] The processor unit 15 further receives instructions (stimulation instructions) received from the control device 20 via the transmitter / receiver unit 11. In accordance with the stimulation instructions, the processor unit 15 determines parameters such as the frequency, intensity (amplitude), and pulse width (if the electrical signal is a pulse signal) of the electrical signal to be applied to the subject as a stimulus, as well as the timing and duration of the stimulus. The processor unit 15 then controls the stimulation circuit unit 13 to apply a stimulus of an electrical signal specified by the determined parameters. The operation of the processor unit 15 will be described later.

[0020] The control device 20 is placed outside the body of a subject, which is an animal including a human, at a position where wireless communication is possible with the implant device 10. For example, the control device 20 is a wearable device (a so-called wearable device) that is attached to the body surface of the subject.

[0021] The transmitter-receiver 21 receives the detection information transmitted by the implant device 10 and outputs it to the control unit 22. Furthermore, the transmitter-receiver 21 transmits the instructed information to the implant device 10 in accordance with an instruction input from the control unit 22. Furthermore, in one example of the present embodiment, the transmitter-receiver 21 may supply power to the implant device 10 wirelessly.

[0022] The control unit 22 is a program-controlled device such as a CPU, and operates according to a program stored in the storage unit 23. In the example of this embodiment, the control unit 22 receives detection information transmitted by the implant device 10 from the transmitter-receiver 21. Then, based on the received detection information, the control unit 22 determines the content of the stimulation to be applied to the subject by the implant device 10, and instructs the transmitter-receiver 21 to transmit a stimulation instruction representing the determined stimulation to the implant device 10. The operation of the control unit 22 will be described in detail later.

[0023] The storage unit 23 is a memory device or the like, and stores a program executed by the control unit 22. This program may be provided by being stored in a computer-readable, non-transitory recording medium and copied to the storage unit 23. The storage unit 23 also operates as a work memory for the control unit 22.

[0024] The communication unit 24 is a network interface that performs data communication via, for example, a wireless LAN or a mobile phone network, and sends data to a specified destination via a communication means such as a network in accordance with instructions input from the control unit 22. The communication unit 24 also outputs data received via a communication means such as a network to the control unit 22.

[0025] The power supply unit 25 supplies power to each unit of the control device 20. When the transmitter / receiver unit 21 wirelessly supplies power to the implant device 10, the power supply unit 25 also supplies the power.

[0026] Next, a description will be given of an example of the operation of the control unit 22 of the control device 20. In this example of the present embodiment, the control unit 22 executes a program stored in the storage unit 23, thereby realizing a configuration that functionally includes a receiving unit 221, a stimulus determining unit 222, and an instruction sending unit 223, as exemplified in FIG.

[0027] The receiving unit 221 receives detection information that is the detection result of an electrical signal that is a physiological signal of a subject and that is detected by the implant device .

[0028] The stimulus determination unit 222 determines the content of the stimulus to be applied to the subject by the implant device 10 based on the detection information received by the receiving unit 221. Here, the detection information represents the electrical signal detected by the implant device 10 at a predetermined detection site within the subject, as described above. The stimulus determination unit 222 uses this detection information to acquire information related to the time change of the physiological signal at the predetermined site within the subject. For example, if the detection information includes information representing one electrical signal resulting from a single detection, the stimulus determination unit 222 accumulates and stores multiple detection information to acquire information representing the time change of the electrical signal (the physiological signal at the predetermined site within the subject). This information representing the time change is time-domain information. However, due to noise, this time-domain information does not produce the ideal waveform shown in FIG. 7(a). Instead, a signal sequence showing only a rough trend is obtained, as shown in FIG. 7(b), for example, when sampled at 2000 Hz. Therefore, time-domain information alone does not clearly capture changes in the response to stimulation, such as nerve stimulation.

[0029] Therefore, as an example, the stimulus determination unit 222 converts this time domain information, which represents the time change of the physiological signal at a predetermined site in the subject's body, into frequency domain information. By converting it into frequency domain information, changes in the response to the stimulus can be detected relatively easily. A well-known method such as FFT (Fast Fourier Transform) can be used for the conversion into frequency domain information.

[0030] Specifically, Figure 7(c) shows the waveform obtained by converting the signal shown in Figure 7(b) into frequency domain information. Figure 7(c) shows the signal strength between 300 Hz and 400 Hz (the change in signal strength over time in the frequency domain) of the waveform of Figure 7(b) converted sequentially into frequency domain information for 1.024 seconds (2048 samples, i.e., when sampling at 2000 Hz, the number of samples for 1.024 seconds is 2048) using FFT. It can be seen from the envelope in Figure 7(c) that a waveform pattern approximating the ideal signal (Figure 7(a)) appears.

[0031] That is, the stimulation determination unit 222 converts the time change of the electrical signal into information on the signal intensity for each frequency component by using FFT or the like. Specifically, the stimulation determination unit 222 converts the time change of the electrical signal into information on the signal intensity for each frequency component by using a predetermined 2 n If the information represents the detection results of electrical signals less than the number of times (n is a natural number greater than or equal to 1), 2 n The electrical signal detection results are accumulated and stored in the storage unit 23 until the detection results for the number of times are obtained.

[0032] Then, the stimulus determination unit 222 determines whether the stored n The detection results of the electrical signals obtained once are used as information relating to the time change of physiological signals at a predetermined site in the subject's body, and this information relating to the time change of physiological signals is converted into frequency domain information by FFT. The stimulation determination unit 222 determines the content of the stimulation to be applied to the subject by the implant device 10 based on the frequency domain information obtained by the conversion.

[0033] For example, the stimulus determination unit 222 determines the content of the stimulus by referring to stimulus setting information that associates a plurality of different stimulus application conditions with information that indicates the content of the stimulus corresponding to each stimulus application condition, which is stored in advance in the storage unit 23. This stimulus setting information is set in advance by a predetermined method, provided by a personal computer (PC) or the like via wired or wireless connection, and stored in the storage unit 23.

[0034] An example of the stimulus setting information is shown in Fig. 6. The stimulus setting information associates stimulus application conditions (C) with information (S) that indicates the content of the stimulus, and the stimulus application conditions (C) include, for example, information on frequency bands and information on signal strength in the frequency bands.

[0035] The information (S) representing the content of the stimulus includes information such as the frequency of the stimulus (pulse signal) to be applied, the intensity of the stimulus, the pulse width of the stimulus, and the duration of application of the stimulus.

[0036] In the example of Figure 6, for example, a stimulus application condition in which the intensity of a signal F of a predetermined frequency component (for example, a signal between 300 Hz and 400 Hz) exceeds a predetermined first threshold value θ1 and is less than a second threshold value θ2 (where θ2 > θ1) is associated with information indicating the content of the stimulus, such as "apply a relatively weak stimulus of frequency f1 (e.g., with an amplitude of 0.5 mA)" (predetermined, for example, as f1 = 14 Hz).

[0037] In addition, when the intensity of the signal F exceeds the second threshold value θ2 and is less than the third threshold value θ3 (where θ3>θ2), information representing the content of the stimulus, "a moderately strong stimulus of frequency f2 (e.g., amplitude 0.7 mA) is applied" (again, this is predetermined, for example, as f2=20 Hz), is associated with the stimulus application condition.

[0038] Similarly, information indicating the content of the stimulus to be applied when each of the plurality of different stimulus application conditions is satisfied is associated with each other. Note that the stimulus application conditions may include a condition related to one of the thresholds, such as when the intensity of the signal F exceeds the N-th threshold θN.

[0039] The stimulus determination unit 222 refers to frequency domain information obtained by FFT. For example, when the stimulus setting information in the example of Figure 6 is determined, it refers to the information on the signal strength between 300 Hz and 400 Hz among the information, and if the signal strength represented by the information exceeds the first threshold value θ1 and is less than the second threshold value θ2, the stimulus application condition in the first column of Figure 6 is satisfied, and therefore determines the content of the stimulus to be applied as "apply a stimulus with a frequency f1 = 14 Hz and an amplitude of 0.5 mA", which is the content of the stimulus determined by the corresponding information.

[0040] When the frequency domain information obtained by FFT does not satisfy any of the stimulus application conditions included in the stimulus setting information, for example, in the example of Figure 6, when the intensity of a signal of a predetermined frequency component (for example, a signal of 300 Hz to 400 Hz) F is less than a predetermined first threshold value θ1, the stimulus determination unit 222 may determine that "no stimulus should be applied" or may determine to apply a stimulus that is predetermined as a default.

[0041] The stimulus determination section 222 outputs information indicating the content of the stimulus determined by the method exemplified here to the instruction sending section 223.

[0042] The instruction sending unit 223 sends a stimulation instruction indicating the content of the stimulation determined by the stimulation determining unit 222 to the implant device 10.

[0043] The stimulation setting information used here may be determined based on the detection result of an electrical signal representing a physiological signal, which is acquired by the implant device 10.

[0044] Specifically, in one example of this embodiment, an information processing device such as a computer communicatively connected to the control device 20 or the implant device 10 acquires information representing time changes in electrical signals representing physiological signals of the subject, which are acquired by the implant device 10 implanted in the subject at predetermined timings (e.g., every 1 / 2000 seconds) within a predetermined period (e.g., 24 hours).The information processing device such as the control device 20 then converts the information acquired from the implant device 10 into information on signal intensity for each frequency component using a method such as FFT.

[0045] The information processing device then extracts signal strength information of a predetermined frequency (e.g., 300 Hz) from the signal strength information for each frequency component obtained by the conversion, and classifies the extracted signal strength information into multiple classes by clustering processing, which can be performed using a widely known method such as the k-means method.

[0046] Here, for example, when the signal intensity information is classified into N classes (N is 3 or more), thresholds θ1, θ2... that distinguish each class are obtained, and stimulus application conditions are set that include a set of thresholds that include any two thresholds selected from these thresholds θ1, θ2... (the set of thresholds is selected so that the ranges defined by each set of thresholds do not overlap with each other).

[0047] Here, the implant device 10 that obtains the detection results that form the basis of the signals to be classified by the clustering process may be implanted in a specific subject (individual) that is fitted with the control device 20 that sets the threshold value, or may be implanted in an individual of the same species as the individual (for example, if the individual is human, it may be implanted in another human, not the individual himself / herself).

[0048] Furthermore, in the explanation so far, the stimulus application conditions are set by comparing the information on the signal strength for each frequency component with a threshold value, but an information processing device such as the control device 20 may use previously obtained information on the signal strength for each frequency component and determine the stimulus application conditions by referring to the time change in the information on the signal strength for each frequency component (for example, the magnitude of change in signal strength per unit time). Also, the control device 20 may refer to information on the signal strength for each frequency component after a stimulus was actually applied in the past, determine the content of the stimulus to be applied, and use this information to set the stimulus setting information.

[0049] Furthermore, this stimulation setting information may be set by a doctor or the like with reference to thresholds or the like determined by the above-mentioned clustering method or the like, or independently of this.

[0050] [Example of operation] Next, a description will be given of the operation of the stimulation system 1 of this embodiment. In the following example, it is assumed that the implant device 10 is implanted in the body of a human subject, and electrodes for providing stimulation are placed at stimulation sites and detection sites used in sacral nerve stimulation therapy.

[0051] The implant device 10 implanted in the human body executes the process illustrated in Fig. 3, for example, once every 30 minutes. In this process, the implant device 10 first detects an electrical signal representing a physiological signal in the human body using an electrode placed at a detection site, and generates detection information representing the detected electrical signal (S11).

[0052] The implant device 10 transmits the generated detection information to the control device 20 placed outside the human body at a predetermined timing (for example, each time detection occurs) (S12). Then, the implant device 10 checks whether or not an instruction has been received from the control device 20 within a predetermined time (S13), and if not (S13: No), returns to step S11 and continues processing.

[0053] On the other hand, the control device 20 receives and stores the detection information sent by the implant device 10 in step S12 (S21).

[0054] The control device 20 is n Step S21 is repeated until detection results of the electrical signal are obtained 2 times (n is a natural number equal to or greater than 1, for example, n=11). n The electrical signals are accumulated and stored (S22). n When the detected information representing the electrical signals is accumulated, 2 n Information representing the time change of the physiological signal at a predetermined site in the subject's body, which is represented by the electrical signal, is converted into information on the signal intensity for each frequency component by FFT (S23).

[0055] The control device 20 determines the content of the stimulus to be applied by referring to the information on the signal strength for each frequency component obtained in step S23 and the predetermined stimulus setting information (S24). In this determination process, as already described, the control device 20 refers to the information on the signal strength for each frequency component, for example, and determines whether the strength of the signal F satisfies the stimulus application condition: (a) The intensity of the signal F of a predetermined frequency component (for example, 300 Hz to 400 Hz, the same applies below) exceeds a first threshold θ1 and is less than a second threshold θ2 (where θ2>θ1). (b) The intensity of the signal F of a predetermined frequency component exceeds a second threshold θ2 and is less than a third threshold θ3 (where θ3>θ2). … It is determined whether any of the following conditions is satisfied.

[0056] Then, for example, when the signal strength information for each referenced frequency component is less than a predetermined first threshold value θ1, and none of the stimulus application conditions included in the stimulus setting information is satisfied, the control device 20 determines that the stimulus to be applied is "no stimulus to be applied."

[0057] Furthermore, when the information on the signal strength for each referenced frequency component satisfies the stimulus application condition that (b) the signal strength of a predetermined frequency component exceeds a first threshold value θ1 and is less than a second threshold value θ2 (where θ2 > θ1), the control device 20 uses information representing the content of the stimulus set in correspondence with the stimulus application condition and determines that the stimulus to be applied is "a stimulus with a frequency of 14 Hz and an amplitude of 0.5 mA."

[0058] Furthermore, when the information on the signal strength for each referenced frequency component satisfies the stimulus application condition that (c) the signal strength of a predetermined frequency component exceeds a second threshold value θ2 and is less than a third threshold value θ3 (where θ3 > θ2), the control device 20 uses information representing the content of the stimulus set in correspondence with the stimulus application condition and determines that the stimulus to be applied is "a stimulus with a frequency of 20 Hz and an amplitude of 0.7 mA."

[0059] The control device 20 sends an instruction indicating the content of the stimulation determined in step S24 to the implant device 10 (S25).

[0060] When the implant device 10 receives an instruction from the control device 20 in step S13 (S13: Yes), it determines parameters such as the frequency and amplitude of the electrical signal to be applied as a stimulus to the target body, that is, the human body in which the implant device 10 is implanted, and controls the current to be flowed to the stimulation site through the electrodes so as to apply the electrical signal stimulus with the determined parameters (S14).

[0061] The stimulus providing system 1 of this embodiment repeats the operations of steps S11 to S14 and steps S21 to S25.

[0062] In this way, in the example of this embodiment, the stimulus to be applied is changed depending on the condition of the target human body or the like, and it is possible to apply a stimulus that suits the condition of the target.

[0063] [Synthesis of frequency domain information] Furthermore, the control device 20 n Instead of determining the content of the stimulation by directly using the information on the signal strength for each frequency component based on the detection information representing the individual electrical signals, steps S21 to S23 of the process illustrated in Figure 3 may be repeatedly executed to obtain the information on the signal strength for each frequency component multiple times.

[0064] In this example, the control device 20 acquires information (2 n The frequency domain information obtained by converting each of the detected electrical signals (information based on the detected electrical signals) using the FFT method may be stored. n The information based on the detection information representing the electrical signals may not overlap with each other, or may include overlapping information. For example, in the first FFT, n Using the detection information representing the detection results up to the 2nd time, the next FFT n +1 to 2 x 2 n It is also possible to use the detection information representing the detection results up to the first FFT...or to allow overlapping and use the first to second FFT. n Using the detection information representing the detection results up to the 2nd time, the next FFT n-1 +1 to 2 n-1 +2 n It is also possible to use detection information representing the detection results up to the first detection time, and so on.

[0065] The control device 20 may then synthesize the frequency domain information from multiple past sessions that it has stored, and determine the content of the stimulation to be applied to the subject by the implant device 10 by referring to the synthesized frequency domain information and the stimulation setting information.

[0066] As a synthesis method, various methods can be used to calculate a predetermined statistical value of the signal strength for each corresponding frequency component, such as accumulating the signal strength for each corresponding frequency component, or accumulating and then dividing by the accumulated number (i.e., calculating the arithmetic mean of the signal strength for each frequency component).

[0067] For example, Figure 8 shows the results of sequentially accumulating every 10 FFT results shown in Figure 7(c). It can be seen that the waveform shown in Figure 8 is closer to the ideal waveform shown in Figure 7(a) than the waveform shown in Figure 7(c). By converting the data into frequency domain information and then calculating averages and other statistical values, changes in physiological signals can be analyzed more clearly and are not affected by temporary noise.

[0068] The control device 20 refers to the synthesis result of the signal intensities of the frequency components (information on the synthesized frequency domain) and the stimulus setting information, and uses the stimulus setting information illustrated in Fig. 6, for example, to determine that the stimulus to be applied is a "stimulus with a frequency of 14 Hz and an amplitude of 0.5 mA" when the arithmetic mean value of the signal intensities of a predetermined frequency component (300 to 400 Hz) obtained multiple times exceeds a first threshold θ1 and is less than a second threshold θ2 (where θ2 > θ1). Also, when the stimulus to be applied is a "stimulus with a frequency of 14 Hz and an amplitude of 0.5 mA" when the arithmetic mean value of the signal intensities of a predetermined frequency component (300 to 400 Hz) obtained multiple times exceeds a second threshold θ2 and is less than a third threshold θ3 (where θ3 > θ2), the control device 20 uses the information representing the content of the stimulus to be applied to determine that the stimulus to be applied is a "stimulus with a frequency of 20 Hz and an amplitude of 0.7 mA" when the stimulus to be applied is a "stimulus with a frequency of 20 Hz and an amplitude of 0.7 mA."

[0069] In this example of the present embodiment, by converting the information into frequency domain information and then calculating statistical values ​​such as averages, it is possible to apply stimuli more appropriately, for example, without being affected by temporary noise being mixed into the signal.

[0070] [Mode of stimulus to be applied] 3, the example shows that the frequency and amplitude of the periodic electrical stimulation are controlled based on the information on the signal strength of each frequency component as the mode of stimulation to be applied, but as already mentioned, this is just one example, and step S24 may further determine the pulse width of the stimulation to be applied, the timing of applying the stimulation, the duration of the stimulation, etc. The mode of stimulation determined based on the signal strength of each frequency component may be determined experimentally.

[0071] In one example of this embodiment, a server device (not shown) communicably connected to control device 20 via a network may determine the content of the stimulus to be applied using the detection information or information on the signal strength for each frequency component obtained based on the detection information. The processing of this server device may be the same as the processing of stimulus determination unit 222 described above.

[0072] In this example, instead of the above-mentioned processing, the control device 20, as processing of the stimulus determination unit 222, sends to the server device the detection information received by the receiving unit 221, or information on the signal strength for each frequency component obtained by converting the information using FFT or the like, and receives information indicating the content of the stimulus to be applied from the server device and outputs it to the instruction sending unit 223.

[0073] [Stimulus trial] Furthermore, the control device 20 according to one example of the present embodiment may transmit, at predetermined timings, test stimulation instructions (trial stimulation instructions) representing a plurality of candidate stimuli, each of which has a different stimulation content, to the implant device 10, and after transmitting the trial stimulation instructions, evaluate the effectiveness of the transmitted trial stimulation instructions using detection information received from the implant device 10. In this example, the control device 20 provides the evaluation result for each stimulation instruction corresponding to the plurality of candidate stimuli to predetermined processing related to determining the stimulation instruction.

[0074] Specifically, the control unit 22 of the control device 20 according to this example realizes a functional configuration including a receiving unit 221, a stimulus determining unit 222′, an instruction sending unit 223, a trial stimulus unit 225, and an evaluating unit 226, as illustrated in Fig. 4. Here, components that perform the same operations as those in the example of Fig. 2 are assigned the same reference numerals, and detailed descriptions thereof will be omitted.

[0075] In this example, the trial stimulation unit 225 sends stimulation instructions representing a plurality of candidate stimuli, each having different stimulation content, at a predetermined timing to the implant device 10. For example, the trial stimulation unit 225 tries stimulation in a predetermined stimulation pattern, as shown in the following example.

[0076] That is, in one example of this embodiment, the trial stimulation unit 225 receives settings, by operation of a doctor or the like, from a personal computer or the like that is communicatively connected via the communication unit 24, for multiple candidate stimuli, which are different from each other in terms of stimulus content, and the timing for sending stimulation instructions representing each candidate stimulus.

[0077] Specifically, (1) Output a stimulus instruction representing a candidate stimulus of 14 Hz, 1.0 mA, and 10 seconds duration. (2)Wait for 30 seconds (3) Output a stimulus instruction representing a candidate stimulus of 15 Hz, 1.0 mA, and 10 seconds duration. (4)Wait for 30 seconds (5) Output a stimulus instruction representing a candidate stimulus of 16 Hz, 1.0 mA, and 10 seconds duration. (6)Wait for 30 seconds … As will be described later, after the trial stimulation unit 225 outputs a stimulation instruction, while it is on standby, the implant device 10 performs electrical stimulation in accordance with the stimulation instruction, and then detects an electrical signal as a physiological signal in the subject's body using the electrode placed at the detection site, and obtains detection information indicating the change in the signal over time.

[0078] In this example, the different stimuli are exemplified by the frequency of the periodic electrical stimuli, but the present embodiment is not limited to this, and may be exemplified by at least one of the amplitude of the periodic electrical stimuli, the duration of the stimuli, the pulse width of the stimuli, and the frequency of the stimuli.Furthermore, in other stimulation modes, for example, when there are multiple (three or more) electrodes of the stimulation circuit unit 13 or when there are multiple stimulation circuit units 13 themselves, that is, when there are multiple candidates for stimulation sites, the stimulation site may be differentiated, and various modifications may be considered as long as different stimuli can be applied to the subject.

[0079] In accordance with the accepted settings, the trial stimulation unit 225 (1) outputs a stimulation instruction representing a candidate stimulation of 14 Hz, 1.0 mA, and a duration of 10 seconds to the implant device 10, and then (2) waits for 30 seconds. The trial stimulation unit 225 also outputs information representing the content of the stimulation instruction output to the implant device 10 to the evaluation unit 226.

[0080] At this time, the implant device 10 receives the stimulation instruction from the control device 20 and, in accordance with the stimulation instruction, determines parameters such as the frequency and amplitude of the electrical signal as the stimulation to be applied to the target body, the human body in which the implant device 10 is implanted. Here, as instructed, an electrical stimulation of 14 Hz, 1.0 mA, and a duration of 10 seconds is applied to the stimulation site of the target body.

[0081] While the trial stimulation unit 225 waits for 30 seconds, the implant device 10 detects an electrical signal as a physiological signal in the subject's body using the electrodes placed at the detection site and stores the detected information indicating the change over time.The implant device 10 then sends the stored detected information to the control device 20 at a predetermined timing thereafter (here, the timing is before the trial stimulation unit 225 outputs the next trial instruction).This detected information is processed by the evaluation unit 226, which will be described later.

[0082] After (2) waiting for 30 seconds, the trial stimulation unit 225 (3) outputs a stimulation instruction representing a candidate stimulation of 15 Hz, 1.0 mA, and a duration of 10 seconds. Then, (4) it waits for 30 seconds. The trial stimulation unit 225 also outputs information representing the content of the stimulation instruction output to the implant device 10 to the evaluation unit 226.

[0083] At this time, the implant device 10 also receives the stimulation instruction from the control device 20 and, in accordance with the stimulation instruction, applies electrical stimulation of 15 Hz, 1.0 mA, and for 10 seconds to the stimulation site of the subject. While the trial stimulation unit 225 waits for 30 seconds, the implant device 10 detects electrical signals as physiological signals within the subject using electrodes placed at the detection site and stores detection information indicating their changes over time. The implant device 10 then transmits the stored detection information to the control device 20 at a predetermined timing thereafter (here, the timing is before the trial stimulation unit 225 outputs the next stimulation instruction, as described above).

[0084] Thereafter, the trial stimulation unit 225 repeats the operation of sending a stimulation instruction representing a candidate stimulation to the implant device 10 in accordance with the setting and waiting for a predetermined time. Every time the implant device 10 receives a stimulation instruction representing a candidate stimulation, it applies an electrical stimulation to the stimulation site of the subject body in accordance with the stimulation instruction, and then detects an electrical signal as a physiological signal within the subject body during the subsequent waiting period of the trial stimulation unit 225 to obtain detection information, and then sends the detection information to the control device 20.

[0085] However, the operation (and its setting) of the trial stimulation unit 225 described above is merely an example, and when another operation is set, the trial stimulation unit 225 will perform an operation according to the setting. For example, instead of waiting for a predetermined time as described above, the trial stimulation unit 225 may determine the timing to output the next stimulation instruction as follows.

[0086] That is, in one example of the trial stimulation unit 225, the trial stimulation unit 225 waits after issuing a stimulation instruction, and when the acceptance unit 221 accepts detection information during this waiting period, the trial stimulation unit 225 determines whether to output the next stimulation instruction based on the accepted detection information. Then, when the trial stimulation unit 225 decides to output the next stimulation instruction, it may output a stimulation instruction representing a stimulation candidate to be output next, according to settings.

[0087] As a specific example, in this case, the trial stimulation unit 225 converts the detection information received by the receiving unit 221 into information on the signal strength for each frequency component (information in the frequency domain) using FFT or the like. Then, the trial stimulation unit 225 may refer to the signal strength information and determine to output a stimulation instruction for the corresponding candidate stimulation when the strength of a signal F of a predetermined frequency component (for example, a signal between 300 and 400 Hz) exceeds a predetermined threshold θ.

[0088] The threshold value used here may also be obtained by processing such as clustering based on multiple pieces of detection information obtained over a predetermined period, as in the example already described.

[0089] In this example of the present embodiment, trial stimulation unit 225 waits until the intensity of signal F of the predetermined frequency component in the frequency domain information obtained by converting the detection information received by reception unit 221 exceeds a predetermined threshold θ, and then (1) outputs a stimulation instruction representing a candidate stimulation of 14 Hz, 1.0 mA, and a duration of 10 seconds. Thereafter, it waits until the intensity of signal F of the predetermined frequency component in the frequency domain information obtained by converting the detection information received by reception unit 221 again exceeds the threshold θ, and then (3) outputs a stimulation instruction representing a candidate stimulation of 15 Hz, 1.0 mA, and a duration of 10 seconds.

[0090] Further, instead of waiting for the timing when a set time has elapsed or the timing determined based on the detection information received by the receiving unit 221 to output a stimulus instruction representing a candidate stimulus, the trial stimulus unit 225 may control the timing of outputting a stimulus instruction representing a candidate stimulus by a combination of the timing when a set time has elapsed and the timing determined based on the detection information received by the receiving unit 221, such as waiting for the specified time when the receiving unit 221 determines based on the detection information received that a stimulus instruction representing a candidate stimulus should be output.

[0091] The evaluation unit 226 receives detection information from the implant device 10 after the trial stimulation unit 225 sends out a stimulation instruction, that is, after receiving information indicating the content of the stimulation instruction sent out from the trial stimulation unit 225. Then, based on the detection information, the evaluation unit 226 evaluates whether or not the stimulation instruction sent out by the trial stimulation unit 225 was effective, or the degree of the effect.

[0092] In one example of this embodiment, the evaluation unit 226 converts the detection information, which is time-domain information, into frequency-domain information using FFT. The evaluation unit 226 then evaluates the degree of effectiveness of the stimulation instruction sent by the trial stimulation unit 225 based on the intensity of a signal F of a predetermined frequency component (for example, a 300 Hz signal). For example, the evaluation unit 226 compares the intensity of the signal F of the predetermined frequency component (for example, a 300 Hz signal) in the detection information for multiple different stimulation instructions sent by the trial stimulation unit 225, and identifies the stimulation instruction corresponding to the detection information with the smallest intensity. The evaluation unit 226 then determines that the identified stimulation instruction is the most effective stimulation instruction and outputs the content of the corresponding stimulation instruction to the stimulation determination unit 222′.

[0093] Furthermore, here we have shown an example in which the intensities of the signal of the above-mentioned specified frequency component (for example, a 300 Hz signal) F in the detection information for multiple different stimulation instructions sent out by the trial stimulation unit 225 are compared, and the stimulation instruction corresponding to the detection information with the smallest intensity is identified. However, this is not limited to this example, and the evaluation unit 226 may also examine the change over time in the intensity of the signal of the above-mentioned specified frequency component (for example, a 300 Hz signal) F in the detection information for multiple different stimulation instructions sent out by the trial stimulation unit 225, and determine the most effective stimulation instruction based on the change over time (for example, the magnitude of the rate of decrease per unit time).

[0094] FIG. 5 shows the trial stimulation unit 225, as in the example above, (1) Output a stimulus instruction representing a candidate stimulus of 14 Hz, 1.0 mA, and 10 seconds duration. (3) Output a stimulus instruction representing a candidate stimulus of 15 Hz, 1.0 mA, and 10 seconds duration. (5) Output a stimulus instruction representing a candidate stimulus of 16 Hz, 1.0 mA, and 10 seconds duration. This is an example of frequency domain information obtained by converting the detection signal obtained after the measurement using FFT, with the horizontal axis representing frequency (Hz) and the vertical axis representing signal strength (arbitrary units).

[0095] 5, the detection signal for (a) the candidate stimulus of 14 Hz, 1.0 mA, and duration 10 seconds has a lower intensity of a signal F of a predetermined frequency component (for example, a 300 Hz signal) than the detection signal for (b) the candidate stimulus of 15 Hz, 1.0 mA, and duration 10 seconds, or the detection signal for (c) the candidate stimulus of 16 Hz, 1.0 mA, and duration 10 seconds. In this case, the evaluation unit 226 determines that the candidate stimulus of (a) 14 Hz, 1.0 mA, and duration 10 seconds, which has the lowest intensity of signal F, is the most effective candidate stimulus.

[0096] Such an operation of the evaluation unit 226 can be realized using widely known processing such as sorting, and therefore further detailed explanation will be omitted here.

[0097] If the intensities of the signals F corresponding to the candidate stimuli determined to be the most effective candidate stimuli based on the determination based on the intensities of the signals F corresponding to the different stimulation instructions are substantially the same, the stimulation instruction with the lower (or higher) frequency (or the stimulation instruction with the smaller or larger amplitude (stimulation intensity)) among the different stimulation instructions may be determined to be the most effective stimulation instruction, and information representing the content of the stimulation instruction may be output. Here, when the intensities of the signals F corresponding to the different stimulation instructions are substantially the same, the determination of which stimulation instruction to select may be made by, for example, selecting a stimulation instruction that is considered to impose a relatively small load on the subject. The stimulation determination unit 222′ performs the same operations as the stimulation determination unit 222 already described, and also receives input of information representing the content of the most effective stimulation instruction output by the evaluation unit 226 and stores the information representing the content of the stimulation instruction.

[0098] Thereafter, similar to the operation of the stimulus determination unit 222 already described, the stimulus determination unit 222′ converts the detection information received by the reception unit 221 into frequency domain information by FFT, and obtains the intensity of a signal F of a predetermined frequency component (for example, a 300 Hz signal). Then, when this intensity is less than a predetermined first threshold θ1, for example, the stimulus determination unit 222′ determines that "no stimulus should be applied." Furthermore, when the intensity of the signal F exceeds the first threshold θ1, the stimulus determination unit 222′ outputs information indicating the content of the stimulus based on the content of the stored stimulus instruction to the instruction sending unit 223.

[0099] Furthermore, the stimulus determination unit 222′ in this example may correct the stored content of the stimulation instruction based on the detection information, for example, based on the intensity of a signal F of a predetermined frequency component (e.g., a 300 Hz signal) obtained by converting the detection information. For example, when the intensity of the signal F exceeds the first threshold θ1 and is less than a second threshold θ2 (where θ2 > θ1), the stimulus determination unit 222′ may correct information representing the amplitude from the stored content of the stimulation instruction, and output information representing the content of the stimulation based on the content of the corrected stimulation instruction to the instruction sending unit 223. Furthermore, when the intensity of the signal F exceeds not only the first threshold θ1 but also the second threshold θ2, the stimulus determination unit 222′ may output information representing the content of the stimulation based on the content of the stimulation instruction to the instruction sending unit 223 without correcting the stored content of the stimulation instruction.

[0100] In this example, when the stored content of the stimulation instruction is “14 Hz, 1.0 mA, duration 10 seconds” as in the above example, and the intensity of the signal F exceeds the first threshold θ1 and is less than the second threshold θ2 (where θ2>θ1), the stimulation determination unit 222′ corrects the stored content of the stimulation instruction to “14 Hz, 0.5 mA, duration 10 seconds,” and outputs information representing the content of the stimulation based on the content of the corrected stimulation instruction to the instruction sending unit 223. On the other hand, when the intensity of the signal F exceeds not only the first threshold θ1 but also the second threshold θ2, the stimulation determination unit 222′ does not correct the stored content of the stimulation instruction, and outputs information representing the content of the stimulation based on the stored stimulation instruction of “14 Hz, 1.0 mA, duration 10 seconds” to the instruction sending unit 223.

[0101] The correction manner described here is an example, and the stimulation determination unit 222′ may correct at least one of the amplitude of the periodic electrical stimulation, the duration of the stimulation, the pulse width of the stimulation, and the frequency of the stimulation based on the detection information.

[0102] In this example, a server device (not shown) that is communicatively connected to the control device 20 via a network may perform processing equivalent to the above-mentioned stimulus determination unit 222' and determine the content of the stimulus to be applied.

[0103] In this case, instead of the above-mentioned processing, the control device 20, as processing of the stimulus determination unit 222′, sends to the server device the detection information received by the receiving unit 221, or information on the signal strength for each frequency component obtained by converting the information using FFT or the like, and information representing the content of the most effective stimulus instruction output by the evaluation unit 226, and receives information representing the content of the stimulus to be given from the server device and outputs it to the instruction sending unit 223.

[0104] [Example of processing on the implant device side] In this embodiment, the implant device 10 may perform the processing executed by the control device 20 inside the body of the subject. In this example, the implant device 10 detects an electrical signal representing a physiological signal inside the human body using an electrode placed at a detection site, and generates detection information representing the detected electrical signal.

[0105] The implant device 10 in this example accumulates and stores the generated detection information in the memory of the processor unit 15. The implant device 10 then accumulates and stores the generated detection information in the memory of the processor unit 15. n The detection of the electrical signal, generation of the detection information, and storage are repeated until the detection results of the electrical signal are obtained two times (n is a natural number of 1 or more, for example, n=11). n Once the electrical signals are accumulated, the implant device 10 n Information representing the time change of the physiological signal at a predetermined site in the subject's body, represented by the electrical signal, is converted into information on the signal intensity for each frequency component, for example, by FFT.

[0106] The implant device 10 determines the content of the stimulation to be applied by referring to the information on the signal strength for each frequency component obtained by this process and predetermined stimulation setting information. In this example of the present embodiment, the implant device 10 stores predetermined stimulation setting information (similar to that illustrated in FIG. 6). Then, the implant device 10 refers to the information on the signal strength for each frequency component, for example, and determines whether the strength of the signal F satisfies any of the stimulation application conditions included in the stored stimulation setting information.

[0107] Here, when none of the stimulation conditions included in the stimulation setting information stored in the implant device 10 are satisfied, the control device 20 determines that the stimulation to be applied is "no stimulation to be applied."

[0108] Furthermore, when the implant device 10 determines that the signal strength information for each referenced frequency component satisfies any of the stimulation conditions included in the stored stimulation setting information, it acquires information on the content of the stimulation associated with the stimulation condition that is satisfied by the signal strength information for each referenced frequency component.

[0109] Based on the content of the acquired stimulation, the implant device 10 determines parameters such as the frequency and amplitude of the electrical signal to be applied as stimulation to the target body, the human body in which the implant device 10 is implanted, and controls the current to be passed through the electrodes to the stimulation site so as to apply the electrical signal stimulation with the determined parameters.

[0110] The operation of the implant device 10 may be performed, for example, when communication with the control device 20 is unavailable for a period longer than a predetermined period. Furthermore, the stimulation setting information used by the implant device 10 in the above operation may be the same as or different from the stimulation setting information used by the control device 20. For example, the stimulation setting information used by the implant device 10 may be a subset of the stimulation setting information used by the control device 20 (including information indicating some stimulation conditions and the associated stimulation contents).

[0111] Furthermore, when the implant device 10 performs processing such as FFT, the implant device 10 also performs processing such as FFT. n Rather than determining the content of the stimulation by directly using the information on the signal strength for each frequency component based on the detection information representing the individual electrical signals, the detection of the electrical signals, the generation and storage of the detection information, and the process of obtaining the information on the signal strength for each frequency component may be repeatedly performed to obtain the information on the signal strength for each frequency component (information in the frequency domain) multiple times.

[0112] In this example, the implant device 10 acquires information (2 n The frequency domain information obtained by converting each of the detected electrical signals (information based on the detected electrical signals) using the FFT method is stored. n The information based on the detection information representing the electrical signals may not overlap with each other, or may include overlapping information. For example, in the first FFT, n Using the detection information representing the detection results up to the 2nd time, the next FFT n +1 to 2 x 2 n It is also possible to use the detection information representing the detection results up to the first FFT...or to allow overlapping and use the first to second FFT. n Using the detection information representing the detection results up to the 2nd time, the next FFT n-1 +1 to 2 n-1 +2 nIt is also possible to use detection information representing the detection results up to the first detection time, and so on.

[0113] Then, the implant device 10 synthesizes the frequency domain information from the past multiple times that it has stored, and determines the content of the stimulation to be applied to the target body by referring to the synthesized frequency domain information and the stimulation setting information.

[0114] In this example, various methods can be used to combine frequency domain information, such as accumulating the signal strength for each corresponding frequency component, or accumulating and then dividing by the accumulated number (i.e., calculating the arithmetic mean of the signal strength for each frequency component), to find a predetermined statistical value of the signal strength for each corresponding frequency component.

[0115] [Example of using machine learning] In the explanation up to this point, for example, the content of the stimulus instruction output by the stimulus determination section 222 has been assumed to be predetermined, but the embodiment of the present invention is not limited to this.

[0116] For example, for the same species as the subject (human, pig, etc.), a machine learning model may be generated by prior experimentation to learn the relationship between the frequency components (frequency domain information after transformation using FFT, etc.) of the detected information before stimulation is applied (pre-stimulation state) and the content (frequency, amplitude, etc.) of stimulation judged by, for example, a doctor to be effective in improving the pre-stimulation state, and the control device 20 may then perform processing using this machine learning model.

[0117] In this case, the stimulus determination unit 222 receives the detection information and converts the time change of the electrical signal into information on the signal intensity for each frequency component using FFT or the like. Then, in the processing of step S14 illustrated in FIG. 3, the converted information is input to the machine learning model and the content of the stimulus to be applied as the output is determined.

[0118] The processing of the stimulus determination unit 222 in this example may also be executed by a server device communicably connected to the control device 20, as in the example already described.

[0119] [Real-time monitoring function] In addition, in one example of this embodiment, the implant device 10 sequentially transmits detection information representing the electrical signals of the detection results, and the control device 20 then transfers the electrical signals representing the detection information to an external personal computer, smartphone, etc., for display or analysis, thereby enabling real-time monitoring of physiological signals.

[0120] [Application example] The stimulation system 1 of this embodiment can be used, for example, to treat overactive bladder (OAB), fecal incontinence, pain management, epilepsy, Alzheimer's disease, and other symptoms.

[0121] [Effects of the embodiment] As described above, in the embodiment of the present invention, the subject has the implant device 10 implanted in his or her body, and the control device 20 is attached to a position outside the subject's body where it can communicate wirelessly with the implant device 10.

[0122] This control device 20 sequentially receives wirelessly from the implant device 10 implanted in the subject's body, detection information obtained by the implant device 10 detecting electrical signals representing physiological signals at stimulation sites within the subject's body.

[0123] At this time, for the later Fast Fourier Transform (FFT) processing, (1) The implant device 10 accumulates detection information representing electrical signals of a predetermined number of detection results that is a power of 2 (for example, 2048), and then transmits the detection information of the number of detection results that is a power of 2 to the control device 20, or (2) The implant device 10 sends out detection information representing the electrical signal of the detection result less than a predetermined power of 2 (e.g., 2048), for example, one at a time, and the control device 20 accumulates and stores the detection information for the predetermined power of 2 times.

[0124] According to the latter example (2), the implant device 10 may transmit the detection result for each detection without storing the information. In this way, for example, when the detection is performed once every 1 / 2000 seconds (i.e., at a sample rate of 2000 Hz), the implant device 10 does not need to be provided with a high-speed memory with high power consumption in order to shorten the time required for storing the information, or with a large-capacity memory for storing a large amount of information.

[0125] Furthermore, because the detection information is sent sequentially, if a sufficient number of detection results are experimentally obtained to obtain the necessary frequency domain information, the necessary stimulation content can be determined from fewer detection results. For example, if the necessary and sufficient results are obtained from 2048 detection results, it takes about 1 second (when the sample rate is 2000 Hz) to obtain all 2048 detection results. Therefore, even if the following processing is performed, the time from detection to stimulation application can be shortened.

[0126] The control device 20 performs an FFT operation on the obtained detection information (which is information representing the time change of the physiological signal detected at predetermined timings for a number of times that is a power of 2) and obtains the signal strength for each frequency domain of the physiological signal.

[0127] In this case, since the number of data points actually detected is a power of 2, the FFT calculation can be performed without adding missing data using methods such as padding. This not only ensures that the FFT calculation results reflect the actual detection results, but also improves calculation efficiency.

[0128] The control device 20 (3) The above process of obtaining detection information for a power of two times and performing FFT calculations may be repeated multiple times, and the results of each FFT calculation may be combined. Here, the combination may be performed by, for example, accumulation or averaging. In this way, the accuracy of the FFT calculation results can be improved.

[0129] In addition, in this embodiment, stimulus setting information is set in advance in the control device 20, which associates a plurality of different stimulus providing conditions with information representing the content of the stimulus corresponding to each stimulus providing condition.

[0130] The contents of the stimuli to be applied, associated with the different stimulus application conditions, are as follows: the amplitude of the stimulus, the duration of the stimulus, the pulse width of the stimulus, The frequency of the stimulus At least one of them is different from each other.

[0131] The control device 20 then refers to the result of the FFT calculation (or the result of the synthesis if synthesis is performed) and the multiple stimulus providing conditions included in the stimulus setting information, and searches for a stimulus providing condition that is satisfied by the result of the FFT calculation.

[0132] If the stimulation setting information does not include a stimulation condition satisfied by the result of the FFT calculation, the control device 20 may not apply a stimulation. On the other hand, when a stimulation condition satisfied by the result of the FFT calculation is found, the control device 20 obtains information on the content of the stimulation to be applied that is associated with the found stimulation condition, and wirelessly transmits to the implant device 20 an instruction to apply the stimulation represented by the information.

[0133] When the implant device 20 receives an instruction to apply stimulation from the control device 20, it applies stimulation to a predetermined stimulation site in accordance with the instruction.

[0134] In this way, in this embodiment, it is possible to divide the state of the detected physiological signal into a plurality of patterns and to apply different stimuli for each pattern. [Explanation of symbols]

[0135] 1 Stimulation system, 10 implant device, 11 transmitter / receiver unit, 12 power supply unit, 13 stimulation circuit unit, 14 sensor unit, 15 processor unit, 20 control device, 21 transmitter / receiver unit, 22 control unit, 23 memory unit, 24 communication unit, 25 power supply unit, 221 reception unit, 222, 222' stimulation determination unit, 223 instruction transmission unit, 225 trial stimulation unit, 226 evaluation unit.

Claims

1. A control device disposed outside the body of a subject, which is an animal including a human, at a position capable of wirelessly communicating with an implant device implanted in the body of the subject, the implant device repeatedly detects an electrical signal as a physiological signal at a predetermined site in the subject body at predetermined timings and wirelessly transmits detection information representing the detected electrical signal; The control device a receiving means for receiving the detection information transmitted by the implant device; a determination means for obtaining information relating to a time change of a physiological signal at a predetermined site in the subject's body using the received detection information, and determining the content of a stimulus to be applied to the subject by the implant device based on the information relating to the time change; a sending means for sending a stimulation instruction representing the determined stimulation to the implant device; storing stimulus setting information that associates a plurality of different stimulus application conditions with information that represents the content of the stimulus corresponding to each stimulus application condition; the stimulus application condition includes a condition related to information in the frequency domain; The determination means is a control device that uses the received detection information to acquire information related to time changes in physiological signals at a specified location within the subject's body, and determines the content of the stimulation to be applied to the subject by the implant device by referring to frequency domain information obtained by converting the acquired information and the stimulation setting information.

2. 10. The control device of claim 1, the information relating to the time change is information in the time domain that represents a time change of the electrical signal detected by the implant device, The determination means is a control device that converts the acquired information related to the time change into information in the frequency domain and determines the content of the stimulation to be applied to the subject by the implant device based on the information in the frequency domain.

3. 3. The control device of claim 2, The determining means is a control device that converts the acquired information relating to the time change into information in the frequency domain by fast Fourier transform.

4. 10. The control device of claim 1, trial stimulation means for transmitting stimulation instructions representing a plurality of candidate stimuli, each of which has a different stimulation content, to the implant device at a predetermined timing; and an evaluation means for evaluating an effect of the transmitted stimulation instruction by using detection information received from the implant device after the transmission of the stimulation instruction by the trial stimulation means, A control device that provides the evaluation results for each of the stimulus instructions corresponding to the plurality of candidate stimuli to a predetermined process related to determining the stimulus instruction.

5. 5. The control device of claim 4, each of the plurality of candidate stimuli is a stimulus based on a periodic electrical signal; - the amplitude of the stimulus, - the duration of the stimulus; - the pulse width of the stimulus; - The frequency of the stimulus A control device in which at least one of the candidate stimuli is different from each other.

6. 10. The control device of claim 1, the implant device repeatedly detects an electrical signal representing a physiological signal at a predetermined site within the subject body at predetermined timings, and wirelessly transmits detection information representing the detected electrical signal each time the implant device detects the electrical signal; The determination means of the control device accumulates and stores the detection information received from the implant device until 2n detection results of electrical signals are obtained, converts the stored 2n detection results of electrical signals as information related to time changes in physiological signals at a specified site within the subject's body into frequency domain information using a fast Fourier transform method, and determines the content of the stimulation to be applied to the subject by the implant device based on the frequency domain information.

7. 7. The control device of claim 6, The determination means is a control device that converts information related to time changes in physiological signals at a specified site within the subject's body, which has been acquired multiple times in the past, into frequency domain information using a fast Fourier transform method, combines the frequency domain information from the multiple past times, and determines the content of the stimulation to be applied to the subject by the implant device based on the combined frequency domain information.

8. A control device according to any one of claims 1 to 7, The determination means is a control device that converts information relating to time changes in physiological signals at a specified site within the subject's body, which has been acquired multiple times in the past, into frequency domain information using a fast Fourier transform method, combines the frequency domain information from the multiple past times, and determines the content of the stimulation to be applied to the subject by the implant device by referring to the combined frequency domain information and the stimulation setting information.

9. an implant device to be implanted into a subject, which is an animal, including a human; a control device disposed outside the subject's body at a position capable of wirelessly communicating with the implant device; A stimulus delivery system comprising: The implant device includes: a detection means for repeatedly detecting an electrical signal representing a physiological signal at a predetermined site in the subject's body at predetermined timings; a transmitting / receiving means for transmitting detection information representing the detected electrical signal and receiving a stimulation instruction representing a stimulation to be applied to the subject from the control device; and applying means for applying electrical stimulation to a predetermined site within the subject body based on the stimulation instruction received by the transmitting / receiving means, The control device a receiving means for receiving detection information transmitted by the implant device; a determination means for obtaining information relating to a time change of a physiological signal at a predetermined site in the subject's body using the received detection information, and determining the content of a stimulus to be applied to the subject by the implant device based on the information relating to the time change; a sending means for sending a stimulation instruction representing the determined stimulation to the implant device; storing stimulus setting information that associates a plurality of different stimulus application conditions with information that represents the content of the stimulus corresponding to each stimulus application condition; the stimulus application condition includes a condition related to information in the frequency domain; The determination means uses the received detection information to acquire information relating to time changes in physiological signals at a predetermined site within the subject's body, and determines the content of the stimulation to be applied to the subject by the implant device by referring to frequency domain information obtained by converting the acquired information and the stimulation setting information.

10. A control method for a control device that is implanted in a subject's body, which is an animal including a human, and is communicatively connected to an implant device that repeatedly detects an electrical signal representing a physiological signal at a predetermined site in the subject's body at predetermined timings, and that is located outside the subject's body at a position where it can wirelessly communicate with the implant device implanted in the subject's body, comprising: The control device holds stimulus setting information that associates a plurality of different stimulus application conditions with information that represents the content of the stimulus corresponding to each stimulus application condition; the stimulus application condition includes a condition related to information in the frequency domain; a receiving means for receiving detection information representing a detection result of the electrical signal transmitted by the implant device; a determination means, using the received detection information, to acquire information relating to time changes of physiological signals at a predetermined site in the subject's body, and referring to frequency domain information obtained by converting the acquired information and the stimulation setting information, determines content of the stimulation to be applied to the subject by the implant device based on the information relating to the time changes; A control method for a control device, wherein a sending means sends a stimulation instruction representing the determined stimulation to the implant device.

11. a control device that is implanted in a subject's body, which is an animal including a human, and is communicatively connected to an implant device that repeatedly detects an electrical signal representing a physiological signal at a predetermined site in the subject's body at predetermined timings, and that is disposed outside the subject's body at a position where it can wirelessly communicate with the implant device implanted in the subject's body, and that holds stimulation setting information that associates a plurality of different stimulation conditions with information representing the content of the stimulation corresponding to each of the stimulation conditions, and the stimulation conditions include conditions related to information in the frequency domain; a receiving means for receiving detection information representing a detection result of the electrical signal transmitted by the implant device; a determination means for obtaining information relating to a time change of a physiological signal at a predetermined site in the subject's body using the received detection information, and determining the content of a stimulus to be applied to the subject by the implant device based on the information relating to the time change; a sending means for sending a stimulation instruction representing the determined stimulation to the implant device; It functions as When functioning as the determination means, the program causes the control device to use the received detection information to acquire information relating to time changes in physiological signals at a specified site within the subject's body, and to determine the content of the stimulation to be applied to the subject by the implant device by referring to frequency domain information obtained by converting the acquired information and the stimulation setting information.

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