A brain electrode module integrating stimulation and testing functions and a control method thereof

Abstract

The present invention relates to the technical field of brain electrode modules, and the present invention discloses a brain electrode module with integrated stimulation and testing functions and a control method thereof. The brain electrode module includes a control chip and brain electrodes, the brain electrodes have multiple channels, and are connected to the welding points of the control chip accordingly. Since the control chip includes a processor and multiple pixel circuits, each pixel circuit corresponds to a channel of the brain electrode, so that the processor can control the opening and closing of the corresponding brain electrode channel by controlling the opening and closing of a single pixel circuit, so as to realize fixed-point signal stimulation or testing. The brain electrode module provided by the present application has the advantages of high integration, high signal stimulation accuracy and high flexibility.

Description

Technical Field

[0001] The present invention relates to the technical field of brain electrode modules, and in particular to a brain electrode module integrating stimulation and testing functions and a control method thereof. Background Art

[0002] Brain-computer interface is a multidisciplinary cross-technology involving neuroscience, signal detection and signal processing, and has important research significance and huge application potential in the fields of biomedicine, neurorehabilitation and intelligent robotics. It establishes a direct communication and control channel between the human brain and a computer or other electronic device, collects EEG signals from the cerebral cortex, and converts them into signals that can be recognized by the computer through amplification, filtering, A / D conversion, etc., then pre-processes the signals, extracts characteristic signals, and then uses these characteristics for pattern recognition, and finally converts them into specific instructions to control external devices, thereby achieving control of external devices.

[0003] Before collecting EEG signals, in order to conduct targeted research on the brain, it is necessary to stimulate brain points. Stimulation can be mainly divided into voltage stimulation and current stimulation according to the mode. Voltage mode stimulation has higher energy efficiency and is relatively simple in design. However, due to changes in tissue impedance, the charge delivered to the tissue cannot be controlled, the homeotropic current between electrodes cannot be well controlled, and the resolution accuracy of the stimulation amplitude is not high. In addition, when the charge injected into the tissue is not cleared in time and continues to accumulate at the electrode-tissue contact surface, irreversible electrochemical reactions will occur, leading to tissue damage and electrode electrolysis. Therefore, charge balancing technology is required to regularly eliminate residual charges. The most commonly used stimulation scheme is bidirectional current stimulation, which is generally composed of two highly matched current sources, a working electrode and a reference electrode. Cathodic stimulation is used to trigger action potentials, and anodic stimulation is used for charge compensation. Highly matched bidirectional currents of equal amplitude and opposite polarity are the key to ensuring that there is no charge accumulation in neural tissue and safe experiments. Although current mode stimulation is relatively more precise, it has higher requirements in terms of electronic hardware design. It is necessary to set up a digital-to-analog converter and a current / voltage conversion module, which increases the complexity of system integration. The stimulation voltage is greatly affected by the electrode impedance. Especially in multi-channel stimulation, the power supply voltage needs to ensure the minimum necessary voltage for various loads to achieve the required power efficiency. Moreover, the EEG electrode device with stimulation function in the prior art can only achieve fixed channel stimulation, which cannot meet the diversified and high-throughput requirements of future stimulation needs. Summary of the invention

[0004] The present invention aims to solve the technical problems in the prior art that the stimulation device has a complex structure, high cost and a single stimulation type.

[0005] To solve the above technical problems, the present application discloses, on one hand, a brain electrode module integrating stimulation and testing functions, which includes a control chip and brain electrodes;

[0006] The brain electrode comprises a contact electrode structure and a pad structure connected thereto, wherein the contact electrode structure is used to contact the scalp layer;

[0007] The pad structure includes N solder joints; N is an integer greater than or equal to 2;

[0008] The contact electrode structure comprises N contact electrodes; the N welding points are connected to the N contact electrodes in a one-to-one correspondence;

[0009] The N contact electrodes include M first contact electrodes and M second contact electrodes; M is an integer greater than or equal to 1; the M first contact electrodes correspond to the M second contact electrodes one by one, and the distance between the corresponding first contact electrodes and the second contact electrodes is less than or equal to a first preset distance;

[0010] The control chip includes a connected processor and N pixel circuits; the N pixel circuits are connected to the N welding points in a one-to-one correspondence;

[0011] The processor is used to control the opening or closing of any one of the N contact electrodes by controlling the conduction or disconnection of any one of the N pixel circuits; and when any one of the pixel circuits is turned on, the processor controls any one of the pixel circuits to output a stimulation signal or a test signal to stimulate the target brain by any one of the contact electrodes or to control the corresponding pixel circuit.

[0012] Optionally, the contact electrode structure further includes a flexible substrate and an insulating layer;

[0013] The N contact electrodes are disposed on the flexible substrate;

[0014] The insulating layer is arranged on the N contact electrodes, and the insulating layer comprises N electrode holes, and the N electrode holes correspond to the N contact electrodes one by one.

[0015] Optionally, the top of the flexible substrate includes a first side and a second side that are opposite;

[0016] The M first contact electrodes are located on the first side;

[0017] The M second contact electrodes are located on the second side;

[0018] There is a second preset distance between adjacent first contact electrodes; the second preset distance is greater than or equal to the first preset distance;

[0019] There is a second preset distance between adjacent second contact electrodes;

[0020] The processor controls the first pixel circuit among the N pixel circuits to output a first stimulation signal at the current moment, and controls the second pixel circuit among the N pixel circuits to output a second stimulation signal at the next moment; the first stimulation signal is a signal with the same amplitude, phase and shape as the second stimulation signal; the first contact electrode corresponding to the first pixel circuit corresponds to the second contact electrode corresponding to the second pixel circuit.

[0021] Optionally, the top of the flexible substrate includes a first side and a second side that are opposite;

[0022] The N contact electrodes form a contact electrode set;

[0023] The contact electrode set includes a first contact electrode set and a second contact electrode set;

[0024] The first contact electrode set is located at the first side;

[0025] The second contact electrode set is located on the second side;

[0026] The first contact electrodes and the second contact electrodes in the first contact electrode set are alternately arranged along the length direction of the flexible substrate; the sum of the number of the first contact electrodes and the number of the second contact electrodes in the first contact electrode set is equal to M;

[0027] The first contact electrodes and the second contact electrodes in the second contact electrode set are alternately arranged along the length direction of the flexible substrate; the sum of the number of the first contact electrodes and the number of the second contact electrodes in the second contact electrode set is equal to M;

[0028] The processor controls the first pixel circuit among the N pixel circuits to output a first stimulation signal at the current moment, and controls the second pixel circuit among the N pixel circuits to output a second stimulation signal at the next moment; the first stimulation signal is a signal with the same amplitude, phase and shape as the second stimulation signal; the first contact electrode corresponding to the first pixel circuit corresponds to the second contact electrode corresponding to the second pixel circuit.

[0029] Optionally, the arrangement of the contact electrodes in the first contact electrode set is the same as the arrangement of the contact electrodes in the second contact electrode set; or, the arrangement of the contact electrodes in the first contact electrode set is opposite to the arrangement of the contact electrodes in the second contact electrode set.

[0030] Optionally, each pixel circuit of the N pixel circuits includes a first capacitor, a first switch, a second switch, a third switch and a fourth switch;

[0031] The first end of the first capacitor is connected to the signal input line, and the second end of the first capacitor is connected to the first end of the second switch;

[0032] The first end of the first switch is connected to the second end of the first capacitor, and the second end of the first switch is connected to the signal input line; the signal input line is connected to the processor;

[0033] The second end of the second switch is connected to the first end of the third switch, and the third end of the second switch is connected to a horizontal control signal line; the horizontal control signal line is connected to the processor;

[0034] The second end of the third switch is connected to the first end of the fourth switch, and the third end of the third switch is connected to the vertical control signal line; the vertical control signal line is connected to the processor;

[0035] A first end of the fourth switch is connected to the corresponding solder joint, and a second end of the fourth switch is connected to the test signal processing circuit;

[0036] The first switch outputs a stimulation signal or a test signal to the corresponding contact electrode by cooperating with the fourth switch;

[0037] The processor inputs a stimulation signal or a test signal to the pixel circuit through the signal input line;

[0038] The processor controls the opening or closing of the second switch through the horizontal control signal line;

[0039] The processor controls the opening or closing of the third switch through the vertical control signal line.

[0040] Optionally, each pixel circuit further includes a second capacitor and a fifth switch;

[0041] The first end of the second capacitor is connected to the first end of the fourth switch, and the second end of the second capacitor is connected to the corresponding welding point;

[0042] A first end of the fifth switch is connected to the first end of the capacitor, and a second end of the fifth switch is connected to the second end of the capacitor;

[0043] The processor controls the pixel circuit to output direct current or alternating current by controlling the fifth switch to be turned on or off.

[0044] Optionally, the number N includes 64, 240 or 1024.

[0045] Optionally, the signal input line includes three sub-signal input lines, and the phase difference between adjacent sub-signal input lines arranged along a preset direction is 120 degrees.

[0046] On the other hand, the present application also discloses a control method for a brain electrode module, which is applied to the brain electrode module, the brain electrode module includes a control chip and a brain electrode; the brain electrode includes a connected contact electrode structure and a pad structure, the contact electrode structure contacts the scalp layer; the pad structure includes N solder joints; N is an integer greater than or equal to 2; the contact electrode structure includes N contact electrodes; the N solder joints are connected to the N contact electrodes in a one-to-one correspondence; the N contact electrodes include M first contact electrodes and M second contact electrodes; N is an integer greater than or equal to 1; the M first contact electrodes are in a one-to-one correspondence with the M second contact electrodes, and the distance between the corresponding first contact electrodes and the second contact electrodes is less than or equal to a first preset distance; the control chip includes a connected processor and N pixel circuits; the N pixel circuits are connected to the N solder joints in a one-to-one correspondence, and the control method includes the following steps:

[0047] Obtaining site control signals;

[0048] Controlling the pixel circuit at the corresponding site to be turned on based on the site control signal;

[0049] Receive function control signals;

[0050] Based on the functional control signal, the pixel circuit is controlled to output a stimulation signal or a test signal to achieve stimulation of the target brain by the contact electrode or control of the corresponding pixel circuit.

[0051] By adopting the above technical solution, the brain electrode module provided by this application has the following beneficial effects:

[0052] The brain electrode module disclosed in the present application includes a control chip and brain electrodes. The brain electrodes have multiple channels and are connected to the corresponding solder joints of the control chip. Since the control chip includes a processor and multiple pixel circuits, each pixel circuit corresponds to a channel of the brain electrode, so that the processor can control the opening and closing of the corresponding brain electrode channel by controlling the opening and closing of a single pixel circuit to achieve fixed-point signal stimulation or testing. The pixel circuit is connected to the processor, so that based on the control signal received by the processor, the corresponding switch in the pixel circuit is controlled to be turned on or off, thereby controlling whether the input of the corresponding channel is a stimulation signal or a test signal. The brain electrode module provided by the present application has the advantages of high integration, high signal stimulation accuracy and high flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments 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 creative work.

[0054] Figure 1 This is a schematic diagram of the structure of an optional brain electrode module for this application;

[0055] Figure 2 This is a schematic diagram of the structure of an optional pixel circuit of the present application;

[0056] Figure 3 This is a schematic diagram of the structure of another optional pixel circuit of the present application;

[0057] Figure 4 This is a schematic diagram of the structure of an optional parallel pixel circuit of the present application;

[0058] Figure 5 This is a schematic diagram of the arrangement of the first optional contact electrodes of the present application;

[0059] Figure 6 This is the potential distribution model diagram of the contact electrode structure at time t1;

[0060] Figure 7 This is the potential distribution model diagram of the contact electrode structure at time t2;

[0061] Figure 8 An optional equivalent circuit diagram of the present application when the contact electrode is inserted into the brain tissue in the working state;

[0062] Fig. 9 This is a schematic diagram of the arrangement of the second optional contact electrodes of the present application;

[0063] Fig.10 This is a schematic diagram of the arrangement of the third optional contact electrodes of the present application;

[0064] Fig.11 This is a flow chart of an optional control method of a brain electrode module of the present application.

[0065] The following is a supplementary description of the attached drawings:

[0066] 1-control chip; 2-brain electrode; 21-contact electrode structure; 211-first contact electrode; 212-second contact electrode; 22-pad structure. DETAILED DESCRIPTION

[0067] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0068] The term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present application. In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present application. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may include one or more of the features explicitly or implicitly. Moreover, the terms "first", "second", etc. are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described here can be implemented in an order other than those illustrated or described here.

[0069] For the purpose of the following detailed description, it should be understood that the present invention may adopt various alternative changes and step sequences, unless expressly specified to the contrary. In addition, except in any operating examples, or otherwise indicated, all numbers representing the amount of ingredients used in the specification and claims should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise indicated, the numerical parameters set forth in the following specification and the attached claims are approximate values ​​that vary according to the desired performance to be obtained by the present invention. At least it is not intended to limit the application of the doctrine of equivalents to the scope of the claims, and each numerical parameter should at least be interpreted according to the number of reported significant figures and by applying ordinary rounding techniques.

[0070] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0071] When a numerical range is disclosed herein, the above range is deemed to be continuous and includes the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise indicated, all ranges disclosed herein should be understood to include any and all sub-ranges included therein. For example, a specified range from "1 to 10" should be deemed to include any and all sub-ranges between a minimum of 1 and a maximum of 10. Exemplary sub-ranges of ranges 1 to 10 include, but are not limited to, 1 to 6.1, 3.5 to 7.8, 5.5 to 10, etc.

[0072] See also Figure 1 , Figure 1 This is a schematic diagram of the structure of an optional brain electrode module of the present application. The present application discloses, on one hand, a brain electrode module with integrated stimulation and testing functions, which includes a control chip 1 and a brain electrode 1, wherein the brain electrode 1 includes a contact electrode structure 21 and a pad structure 22 connected, wherein the contact electrode structure 21 is used to contact the scalp layer, and the pad structure 22 includes N solder joints; N is an integer greater than or equal to 2, and the contact electrode structure 21 includes N contact electrodes; the N solder joints are connected to the N contact electrodes in a one-to-one correspondence, and the N contact electrodes include M first contact electrodes 211 and M second contact electrodes 212, where M is an integer greater than or equal to 1; the M first contact electrodes 211 are connected to the M second contact electrodes 212 in a one-to-one correspondence. The control chip 1 includes a connected processor and N pixel circuits; the N pixel circuits are connected to the N solder joints in a one-to-one correspondence, and the processor is used to control the on or off of any one of the N contact electrodes by controlling the on or off of any one of the N pixel circuits; and when any one of the pixel circuits is turned on, the processor controls the any one of the pixel circuits to output a stimulation signal or a test signal to stimulate the target brain by the any one of the contact electrodes or to control the corresponding pixel circuit.

[0073] Optionally, the control chip 1 can be MOKOTO, which includes 128×128 pixel circuits. The control chip 1 includes four signal control lines, each signal control line controls a sub-control line on the north and south sides, and each sub-control line has 128 pixel circuits in parallel. Therefore, only 4 signal inputs can achieve a maximum of 4×2×128=1024 stimulation channels, that is, the above N is 1024.

[0074] It should be noted that in order to isolate and protect adjacent sub-control lines, a separation circuit is provided between adjacent sub-control lines. The above-mentioned N pixel circuits are not necessarily all the solder joints of the control chip, but only correspond to the N contact electrodes. In fact, the control chip may include M pixel circuits, where M is an integer greater than N.

[0075] In a possible embodiment, see Figure 2 , Figure 2 This is a schematic diagram of the structure of an optional pixel circuit of the present application. Each pixel circuit includes a first capacitor C1, a first switch S1, a second switch S2, a third switch S3 and a fourth switch S4, the first end of the first capacitor C1 is connected to the signal input line V0, the second end of the first capacitor C1 is connected to the first end of the second switch S2, the first end of the first switch S1 is connected to the second end of the first capacitor C1, the second end of the first switch S1 is connected to the signal input line V0, the signal input line V0 is connected to the processor, the second end of the second switch S2 is connected to the first end of the third switch S3, and the third end of the second switch S2 is connected to the horizontal control signal line S X[n] Connect the lateral control signal line S X[n] The second end of the third switch S3 is connected to the first end of the fourth switch S4, and the third end of the third switch S3 is connected to the longitudinal control signal line S Y[m] Connect the vertical control signal line S Y[m] The processor inputs a stimulation signal or a test signal to the pixel circuit through the signal input line V0; the processor controls the pixel circuit through the horizontal control signal line S X[n] Control the opening or closing of the second switch S2; the processor controls the vertical signal line S Y[m] Control the opening or closing of the third switch S3.

[0076] Optionally, the two selection signal lines, namely the horizontal control signal line S X[n] and the longitudinal control signal line S Y[m] The register in the processor controls the pixel circuit that needs to be operated, so that the pixel circuit that needs to be operated can be selected from the 128×128 pixel circuits, that is, the horizontal control signal line S X[n] and the longitudinal control signal line S Y[m] You can select the number of stimulation channels you want to achieve and select adjustable stimulation channels. Figure 2 S X[n]Indicates the nth row of horizontal control signal lines; S Y[m] Indicates the m-th column vertical control signal line.

[0077] Optionally, the opening or closing of the first switch S1 and the fourth switch S4 can be controlled based on the user's operation. Since the opening and closing of the first switch S1 and the fourth switch S4 will form different control signals, when the first switch S1 and the fourth switch S4 are closed, "0" will be output, so that the processor controls the voltage signal input to the signal input line V0 from the outside to flow to the output port as a stimulation signal, and then reaches the contact electrode; on the contrary, if the first switch S1 and the fourth switch S4 are closed, "1" will be output, so that the processor controls the voltage signal input to the signal input line V0 from the outside to flow to the amplification circuit as a test signal, and finally outputs the signal through other I / O ports of the chip to an externally connected signal analysis device for observation.

[0078] It should be noted that the test signal mentioned above and below means that when the control chip receives the test signal, it will test the target pixel circuit to determine whether the pixel circuit can operate normally, which can be determined according to different test result signals output by the control chip; in most cases, the control chip mainly collects EEG signals from the target brain. The collected EEG signals can be output by controlling the closing of the fourth switch S4.

[0079] Of course, it is also possible to directly control the first switch S1 and the fourth switch S4 based on an external trigger signal, so that the processor controls the opening or closing of the first switch S1 and the fourth switch S4 based on the trigger signal, thereby realizing the control of the two switches.

[0080] Similarly, other switches in the pixel circuit, such as the second switch S2, the third switch S3 and the fifth switch described below, can be controlled by the above two methods, which are not limited here.

[0081] In a possible embodiment, see Figure 3 , Figure 3This is a schematic diagram of the structure of an optional pixel circuit of the present application. To achieve more stimulation types and meet the analysis of neural signals under diversified stimulation. Each pixel circuit also includes a second capacitor and a fifth switch; the first end of the second capacitor is connected to the first end of the fourth switch S4, and the second end of the second capacitor is connected to the corresponding solder joint; the first end of the fifth switch is connected to the first end of the capacitor, and the second end of the fifth switch is connected to the second end of the capacitor; the processor controls the pixel circuit to output DC or AC by controlling the opening or closing of the fifth switch. In other words, whether the second capacitor is short-circuited can be controlled by controlling the opening or closing of the fifth switch. It can be set that when the fifth switch is disconnected, the output is "0", and the signal input line V0 will input AC, otherwise, when the fifth switch is closed, the second capacitor is short-circuited, and the output is "1", then the signal input line V0 will input DC.

[0082] Optional, see Figure 4 , Figure 4 This is a schematic diagram of the structure of an optional parallel pixel circuit of the present application. Figure 4 The two parallel pixel circuits shown belong to the same row, so they can be controlled by the same horizontal control signal line S X[n] The vertical control signal line of the first pixel circuit is S Y[m] , the vertical control signal line of the second pixel circuit is S Y[m+1] When multiple pixel units are connected in parallel, the same applies, including multiple vertical control signal lines S Y[m] Controlled pixel unit.

[0083] In a feasible embodiment, the contact electrode structure 21 also includes a flexible substrate and an insulating layer, N contact electrodes are arranged on the flexible substrate, the insulating layer is arranged on the N contact electrodes, and the insulating layer includes N electrode holes, and the N electrode holes correspond one-to-one to the N contact electrodes.

[0084] It should be noted that when different pixel circuits correspond to contact electrodes with different arrangements, since the contact electrodes may be located in different areas of the brain tissue and at different distances from the brain tissue, adjusting the correspondence between the contact electrodes and the pixel circuits will affect the area of ​​the stimulated tissue, the number of stimulation channels, the form of stimulation, and the intensity of stimulation, etc.; for example, when the contact electrode is far away from the corresponding site of the brain tissue, in order to achieve the required stimulation energy, it is necessary to increase the intensity of the stimulation voltage / current, and conversely, it is necessary to reduce the intensity of the stimulation voltage / current.

[0085] In order to achieve charge balance, reduce the complexity of external integrated circuits, and reduce the circuit area. Figure 5 , Figure 5This is a schematic diagram of the arrangement of the first optional contact electrode of the present application. The top of the flexible substrate includes a first side and a second side relative to each other, the M first contact electrodes 211 are located on the first side, the M second contact electrodes 212 are located on the second side, and there is a second preset distance between adjacent first contact electrodes 211; the second preset distance is greater than or equal to the first preset distance, and there is the second preset distance between adjacent second contact electrodes 212. The first contact electrode 211 will subsequently input a first stimulation signal, and the second contact electrode 212 will input a second stimulation signal, and the first stimulation signal is a signal with the same amplitude, phase and shape as the second stimulation signal, so as to achieve charge balance in the corresponding brain tissue area.

[0086] It should be noted that the above-mentioned first stimulation signal and second stimulation signal are not instantaneous signals, but signals with equal amplitude, phase and shape formed in a relatively short period of time; the signals formed at time t1 and time t2 below are also signals with equal amplitude, phase and shape.

[0087] The following will be based on Figure 4 The principle of achieving charge balance with the contact electrode structure 21 is described below:

[0088] Figure 4 The contact electrode structure 21 includes 24 pairs of contact electrodes, each of which includes a first contact electrode 211 located on the first side and a second contact electrode 212 located on the second side; it should be understood that when the contact electrode receives a stimulation signal, the brain tissue it contacts will be injected with electric charge, so the surrounding electric potential will also change. Assuming that at time t0, there is no voltage signal input to the first signal input line V1 connected to the first contact electrode 211 and the second signal input line V2 connected to the second contact electrode 212, then the electric potential of the tissue connected to the contact electrode is equal everywhere and is in a relatively balanced state. Figure 6 , Figure 6 is a potential distribution model diagram of the contact electrode structure 21 at time t1. When at time t1, the first signal input line V1 inputs a signal with an amplitude of "1", and the second signal input line V2 inputs a signal with an amplitude of "0", the first contact electrode 211 on the first side forms a high potential due to the injection of charges, and the second contact electrode 212 on the second side forms a relatively low potential, and a potential difference is formed between the adjacent first contact electrode 211 and the second contact electrode 212, so there is I sti From the first contact electrode 211 to the second contact electrode 212, Figure 6 See Figure 7 , Figure 7t2 is a potential distribution model diagram of the contact electrode structure 21. At time t2, the first signal input line V1 inputs a signal with an amplitude of "0", and the second signal input line V2 inputs a signal with an amplitude of "1". The first contact electrode 211 on the first side is at a low potential, and the second contact electrode 212 on the second side is at a high potential. sti From the second contact electrode 212 to the first contact electrode 211. Since the actual distance between the paired first contact electrodes 211 and the second contact electrodes 212 is very close, the current formed by the potential difference can be considered to flow only between the two electrodes and hardly diffuse outward. The equivalent schematic diagram of the loop formed by the first contact electrode 211-tissue-tissue-second contact electrode 212 is as follows: Figure 8 As shown, Figure 8 This is an optional equivalent circuit diagram of the present application when the contact electrode is inserted into the brain tissue. In a very short time, it can be considered that I with equal magnitude and opposite direction is generated at time t1 and time t2. sti Therefore, after time t2, the charges injected into the brain tissue due to stimulation are offset by each other, achieving charge balance. The present application not only solves the charge balance problem by alternately inputting stimulation through two signal lines, avoiding brain tissue damage and electrode electrolysis, but also improves integration and simplifies the external circuit.

[0089] It should be noted that Figure 8 Re is the contact electrode resistance, R and Ci are the equivalent resistance and capacitance in the brain tissue, and Rs is the resistance between the two contact electrode paths.

[0090] In a possible embodiment, see Fig. 9 , Fig. 9 This is a schematic diagram of the arrangement of the second optional contact electrodes of the present application. The N contact electrodes form a contact electrode set, which includes a first contact electrode set and a second contact electrode set, the first contact electrode set is located on the first side, the second contact electrode set is located on the second side, the first contact electrodes 211 and the second contact electrodes 212 in the first contact electrode set are staggered along the length direction of the flexible substrate, the sum of the number of the first contact electrodes 211 and the number of the second contact electrodes 212 in the first contact electrode set is equal to M, the first contact electrodes 211 and the second contact electrodes 212 in the second contact electrode set are staggered along the length direction of the flexible substrate, the sum of the number of the first contact electrodes 211 and the number of the second contact electrodes 212 in the second contact electrode 212 is equal to M, wherein the arrangement of the contact electrodes in the first contact electrode set is the same as the arrangement of the contact electrodes in the second contact electrode 212.

[0091] In another possible embodiment, see Fig.10 , Fig.10This is a schematic diagram of a third optional arrangement of contact electrodes in the present application. The arrangement of the contact electrodes in the first contact electrode set is opposite to the arrangement of the contact electrodes in the second contact electrode 212 .

[0092] It should be noted that the above-mentioned brain electrode module can select the voltage control mode when stimulating brain tissue, and can achieve charge-balanced electrical stimulation by generating a balanced bidirectional voltage pulse in the external circuit and inputting it into the signal input line V0. This method can achieve a total of 1024-channel stimulation with 4 different stimulation waveforms.

[0093] In a feasible embodiment, the number of N includes 64, 240 or 1024.

[0094] In a feasible embodiment, the signal input line V0 includes three sub-signal input lines V0, and the phase difference between adjacent sub-signal input lines V0 arranged along a preset direction is 120 degrees. That is to say, when the electrode position controlled by the three signal lines just forms an angle of 120°, and the three external signal input ports give an initial stimulation with a phase difference of 120°, it is possible to form autonomous power generation, that is, there is no need to supply the stimulation signal from an external voltage generator, but to use the phase difference to make the signal continue. Similarly, using four signal lines to form a phase difference of 90° can also form a four-phase generator, which is an excellent development point in future wireless, sustainable, and energy-saving designs.

[0095] Optionally, when the control chip 1 is a MOKOTO chip and the brain electrode 1 is a 2640-channel device, the pad structure 22 of the brain electrode 1 is a 30×88 solder point array; the distance between adjacent solder points is 200 microns, and the distance between adjacent pixel circuit units in the MOKOTO chip is 100 microns, so the two can be flip-chip welded, thereby improving the integration and ensuring the signal quality; since the distance between adjacent solder points of the brain electrode 1 is twice the distance between adjacent pixel units, the adjacent solder points can be connected to the spaced pixel units, so that the number of solder points that can be connected to the pixel units of MOKOTO is 30×64, and since the MOKOTO chip has only 8 rows of arrays with corresponding signal lines, only 30×8=240 channels can be used for the stimulation part.

[0096] In summary, in the brain electrode module provided by this application, since the control chip 1 includes multiple pixel circuits, corresponding to multiple contact electrodes of the brain electrode 1, it is possible to control the opening of different stimulation channels, realize the stimulation of adjustable sites, and configurable bipolar voltage stimulation to achieve charge balance, reduce the complexity of external integrated circuits, and reduce the circuit area; and the optional DC / AC stimulation can adapt to specific experimental scenarios. This application not only realizes high-channel stimulation, further fills the gap in high-channel stimulation on the market, but also can adapt to changes in different needs in the biomedical field, has higher flexibility, reduces R&D costs, and shortens the experimental cycle.

[0097] See also Fig.11 , Fig.11 This is a flow chart of an optional control method of a brain electrode module of the present application. In another aspect, the present application also discloses a control method of a brain electrode module, which is applied to the above-mentioned brain electrode module, and the control method comprises the following steps:

[0098] S1101: Acquire a site control signal.

[0099] S1102: Controlling the pixel circuit at the corresponding site to be turned on based on the site control signal.

[0100] As described above, the horizontal control signal line S can be controlled by controlling the number of rows. X[n] The number of vertical control signal lines S Y[m] , thereby controlling the opening and closing of the corresponding second switch S2 and the third switch S3 to achieve the conduction of the corresponding pixel circuit as a whole.

[0101] S1103: Receive a function control signal.

[0102] Optionally, the functional control signal may include two types, one is a control signal for controlling the pixel circuit to output a stimulation / test signal; the other is a control signal for controlling the pixel circuit to output a direct current / alternating current.

[0103] S1104: Based on the functional control signal, the pixel circuit is controlled to output a stimulation signal or a test signal to achieve stimulation of the target brain by the contact electrode or control of the corresponding pixel circuit.

[0104] Referring to the above description, the input stimulation signal or test signal can be realized by the signals generated by the opening and closing of the first switch S1 and the fourth switch S4. When it is a stimulation signal, it is input into the brain tissue through the output port, and when it is a test signal, it is input into the amplifier circuit.

[0105] It is also possible to determine whether the stimulation signal input into the pixel circuit is AC or DC by controlling the fifth switch to be turned on or off. The specific implementation method is described above and will not be repeated here.

[0106] The above description is only an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A brain electrode module with integrated stimulation and testing functions, characterized in that: It comprises a control chip (1) and brain electrodes (2); The brain electrode (2) comprises a connected contact electrode structure (21) and a pad structure (22), wherein the contact electrode structure (21) is used to contact the scalp layer; The pad structure (22) includes N solder joints; N is an integer greater than or equal to 2; The contact electrode structure (21) comprises N contact electrodes; the N welding points are connected to the N contact electrodes in a one-to-one correspondence; The N contact electrodes include M first contact electrodes (211) and M second contact electrodes (212); M is an integer greater than or equal to 1; the M first contact electrodes (211) correspond to the M second contact electrodes (212) one by one, and the distance between the corresponding first contact electrodes (211) and the second contact electrodes (212) is less than or equal to a first preset distance; The control chip (1) comprises a connected processor and N pixel circuits; the N pixel circuits are connected to the N welding points in a one-to-one correspondence; The processor is used to control the on or off of any one of the N contact electrodes by controlling the on or off of any one of the N pixel circuits; and when any one of the pixel circuits is on, the processor controls any one of the pixel circuits to output a stimulation signal or a test signal to control the stimulation of the target brain by any one of the contact electrodes or the test of the corresponding pixel circuit; The N contact electrodes constitute a contact electrode set; the contact electrode structure (21) comprises a first side and a second side opposite to each other; the contact electrode set comprises a first contact electrode set and a second contact electrode set, the first contact electrode set is located on the first side, and the second contact electrode set is located on the second side; the first contact electrode (211) and the second contact electrode (212) in the first contact electrode set are arranged in a staggered manner along the length direction of the contact electrode structure, and the second contact electrode set is arranged in the same or opposite manner as the first contact electrode (211) and the second contact electrode (212) in the first contact electrode set, or the first contact electrode set arranges a plurality of first contact electrodes (211) at intervals along the length direction of the contact electrode structure, and the second contact electrode set arranges a plurality of second contact electrodes (212) at intervals along the length direction of the contact electrode structure; the first contact electrode is connected to a first signal input line, and the second contact electrode is connected to a second signal input line; the processor is capable of controlling the first signal input line and the second signal input line to input stimulation signals in an alternating manner to achieve charge balance in the corresponding brain tissue area.

2. The brain electrode module according to claim 1, characterized in that: The contact electrode structure (21) also includes a flexible substrate and an insulating layer; The N contact electrodes are disposed on the flexible substrate; The insulating layer is disposed on the N contact electrodes, and the insulating layer includes N electrode holes, and the N electrode holes correspond to the N contact electrodes one by one.

3. The brain electrode module according to claim 2, characterized in that: The top portion of the flexible substrate includes opposing first and second sides; The M first contact electrodes (211) are located on the first side; The M second contact electrodes (212) are located on the second side; There is a second preset distance between adjacent first contact electrodes (211); the second preset distance is greater than or equal to the first preset distance; The second preset distance exists between adjacent second contact electrodes (212); The processor controls a first pixel circuit among the N pixel circuits to output a first stimulation signal at a current moment, and controls a second pixel circuit among the N pixel circuits to output a second stimulation signal at a next moment; the first stimulation signal is a signal having the same amplitude, phase and shape as the second stimulation signal; and a first contact electrode (211) corresponding to the first pixel circuit corresponds to a second contact electrode (212) corresponding to the second pixel circuit.

4. The brain electrode module according to claim 2, characterized in that: The top portion of the flexible substrate includes opposing first and second sides; The N contact electrodes form a contact electrode set; The contact electrode set includes a first contact electrode set and a second contact electrode set; The first contact electrode set is located on the first side; The second contact electrode set is located at the second side; The first contact electrodes (211) and the second contact electrodes (212) in the first contact electrode set are arranged alternately along the length direction of the flexible substrate; the sum of the number of the first contact electrodes (211) and the number of the second contact electrodes (212) in the first contact electrode set is equal to M; The first contact electrodes (211) and the second contact electrodes (212) in the second contact electrode set are arranged alternately along the length direction of the flexible substrate; the sum of the number of the first contact electrodes (211) and the number of the second contact electrodes (212) in the second contact electrodes (212) is equal to M; The processor controls a first pixel circuit among the N pixel circuits to output a first stimulation signal at a current moment, and controls a second pixel circuit among the N pixel circuits to output a second stimulation signal at a next moment; the first stimulation signal is a signal having the same amplitude, phase and shape as the second stimulation signal; and a first contact electrode (211) corresponding to the first pixel circuit corresponds to a second contact electrode (212) corresponding to the second pixel circuit.

5. The brain electrode module according to claim 4, characterized in that: The arrangement of the contact electrodes in the first contact electrode set is the same as the arrangement of the contact electrodes in the second contact electrode (212); or, the arrangement of the contact electrodes in the first contact electrode set is opposite to the arrangement of the contact electrodes in the second contact electrode (212).

6. The brain electrode module according to claim 1, characterized in that: Each of the N pixel circuits includes a first capacitor, a first switch, a second switch, a third switch and a fourth switch; A first end of the first capacitor is connected to a signal input line, and a second end of the first capacitor is connected to a first end of the second switch; The first end of the first switch is connected to the second end of the first capacitor, and the second end of the first switch is connected to the signal input line; the signal input line is connected to the processor; The second end of the second switch is connected to the first end of the third switch, and the third end of the second switch is connected to a horizontal control signal line; the horizontal control signal line is connected to the processor; The second end of the third switch is connected to the first end of the fourth switch, and the third end of the third switch is connected to the vertical control signal line; the vertical control signal line is connected to the processor; A first end of the fourth switch is connected to the corresponding solder joint, and a second end of the fourth switch is connected to the test signal processing circuit; The first switch outputs a stimulation signal or a test signal to the corresponding contact electrode by cooperating with the fourth switch; The processor inputs a stimulation signal or a test signal to the pixel circuit through the signal input line; The processor controls the second switch to be turned on or off via the horizontal control signal line; The processor controls the opening or closing of the third switch through the vertical control signal line.

7. The brain electrode module according to claim 6, characterized in that: Each pixel circuit further includes a second capacitor and a fifth switch; The first end of the second capacitor is connected to the first end of the fourth switch, and the second end of the second capacitor is connected to the corresponding welding point; A first end of the fifth switch is connected to a first end of the capacitor, and a second end of the fifth switch is connected to a second end of the capacitor; The processor controls the pixel circuit to output direct current or alternating current by controlling the fifth switch to be turned on or off.

8. The brain electrode module according to claim 1, characterized in that: The number of N includes 64, 240 or 1024.

9. The brain electrode module according to claim 6, characterized in that: The signal input line includes three sub-signal input lines, and the phase difference between adjacent sub-signal input lines arranged along a preset direction is 120 degrees.

10. A control method for a brain electrode module, characterized in that: Applicable to a brain electrode module as claimed in any one of claims 1 to 9, the brain electrode module comprises a control chip (1) and a brain electrode (2); the brain electrode (2) comprises a connected contact electrode structure (21) and a pad structure (22), the contact electrode structure (21) contacts the scalp layer; the pad structure (22) comprises N solder joints; N is an integer greater than or equal to 2; the contact electrode structure (21) comprises N contact electrodes; the N solder joints are connected to the N contact electrodes in a one-to-one correspondence; the N contact electrodes comprise M first contact electrodes (211) and M second contact electrodes (212); N is an integer greater than or equal to 1; the M first contact electrodes (211) correspond one-to-one to the M second contact electrodes (212), and the distance between the corresponding first contact electrodes (211) and the second contact electrodes (212) is less than or equal to a first preset distance; the control chip (1) comprises a connected processor and N pixel circuits; the N pixel circuits are connected one-to-one to the N solder joints, and the method comprises the following steps: Obtaining site control signals; Controlling the activation of the pixel circuit at the corresponding site based on the site control signal; Receive function control signals; Based on the functional control signal, the pixel circuit is controlled to output a stimulation signal or a test signal to achieve stimulation of the target brain by the contact electrode or control of the corresponding pixel circuit.

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