A read-write brain-computer interface integrated system and a control method thereof

Abstract

This invention discloses an integrated readable and writable brain-computer interface (BCI) system and its control method, relating to the field of BCI. In this system, a PMUT array vibrates based on a monitored excitation voltage signal to emit a first ultrasonic wave towards the target brain region, thereby achieving acoustic acquisition of blood flow characteristic information of the target brain region. It receives the first ultrasonic echo and generates vibration to feed back a first electrical signal. Based on a modulated excitation voltage signal, it vibrates to emit a second ultrasonic wave, thereby modulating neural activity in the target brain region through acoustic stimulation. When imaging monitoring is activated, the processing module outputs the monitored excitation voltage signal and receives the first electrical signal, thereby reconstructing a functional ultrasound blood flow image and extracting target feature parameters. When modulatory intervention is activated, it outputs a modulatory excitation voltage signal. This scheme constructs a single-modal imaging and modulation integrated closed-loop system based on acoustic monitoring and acoustic modulation, achieving imaging monitoring and modulatory intervention of the target brain region based on the PMUT array, resulting in higher accuracy in system imaging and modulation.

Description

Technical Field

[0001] This invention relates to the field of brain-computer interface technology, and in particular to an integrated system for reading and writing brain-computer interfaces and its control method. Background Technology

[0002] Brain-computer interfaces (BCIs) refer to the creation of a direct connection between the human or animal brain and an external device to enable information exchange. Their core consists of two dimensions: reading and writing. Reading refers to controlling external devices by monitoring and decoding neural activity within the brain through imaging. Writing involves regulating and intervening in the nervous system through external manipulation. Therefore, a readable and writable BCI can achieve both imaging monitoring and regulatory intervention, dynamically adjusting intervention parameters based on real-time imaging monitoring of the target brain region to achieve on-demand control.

[0003] To achieve the above goals, there are currently several implementation methods, such as the electro-acoustic closed-loop control scheme. The corresponding closed-loop system includes an imaging monitoring device and a modulation and intervention device. The imaging monitoring device can monitor and provide feedback on the target brain region in real time using electrical signals. The modulation and intervention device can analyze the feedback to trigger ultrasound modulation and intervention. For example, by implanting EEG electrodes or wireless EEG to monitor the neural activity of the target brain region in real time, when a specific electrical signal (such as epileptiform discharge) is captured, the corresponding modulation and intervention device activates ultrasound modulation and intervention.

[0004] However, this approach has certain technical drawbacks: Firstly, as an electro-acoustic multimodal fusion control scheme, the mechanical effects generated by ultrasound during intervention can easily cause artifact interference on the EEG electrodes, affecting the accuracy of corresponding electrical signal detection. Secondly, in this scheme, imaging monitoring and intervention rely on two separate independent devices, which may lead to spatial alignment errors in practical applications. That is, the brain region aligned by the imaging monitoring device and the brain region aligned by the intervention device are unlikely to be truly consistent in actual space, affecting the accuracy of the imaging system's control. Furthermore, the stacking of independent devices can make the overall brain-computer interface integrated system bulky, limiting its clinical implantation and wearability.

[0005] Therefore, how to provide a more effective integrated solution for reading and writing brain-computer interfaces is an urgent problem to be solved. Summary of the Invention

[0006] In view of this, the present invention provides an integrated brain-computer interface system and its control method, which constructs a single-modal imaging and control integrated closed-loop system of acoustic monitoring and acoustic modulation, and realizes imaging monitoring and control intervention of target brain regions based on PMUT array. The system has higher imaging and control accuracy and lower power consumption.

[0007] To address the aforementioned technical problems, this application provides an integrated read / write brain-computer interface system, including a processing module and a PMUT array based on M PMUT array elements; M is an integer greater than 1. The PMUT array is positioned at a target location inside the brain and is also connected to the processing module. It is used to generate vibrations based on received monitoring excitation voltage signals to emit a first ultrasound wave towards the target brain region. This first ultrasound wave enables acoustic acquisition of blood flow characteristics in the target brain region to receive the corresponding first ultrasound echo. Based on the first ultrasound echo, it generates vibrations to feed back a first electrical signal to the processing module. It also generates vibrations based on received modulation excitation voltage signals to emit a second ultrasound wave towards the target brain region, thereby modulating neural activity in the target brain region through acoustic stimulation. The processing module is used to output the monitoring excitation voltage signal to the PMUT array when imaging monitoring is enabled, and to receive the first electrical signal so as to reconstruct the functional ultrasound blood flow image of the target brain region based on the first electrical signal; to decode and analyze the functional ultrasound blood flow image to extract target feature parameters; and to output the modulation excitation voltage signal to the PMUT array when it is determined to enable modulation intervention based on the target feature parameters.

[0008] Furthermore, the processing module includes a host control module located outside the brain, a transmitting circuit and a receiving circuit deployed on a PCB board; Each PMUT array element is connected to the transmitting circuit and the receiving circuit respectively, and the upper-level control module is connected to the transmitting circuit and the receiving circuit respectively.

[0009] Furthermore, the processing module includes a host control module and a CMOS circuit; The upper-level control module is connected to the PMUT array through the CMOS circuit, and the upper-level control module is located outside the brain; The CMOS circuitry and the PMUT array are integrated into the same target chip so that the target chip can be positioned at a target location inside the brain.

[0010] Furthermore, the monitoring excitation voltage signal is an AC excitation voltage signal with a frequency located within the first frequency range; The controlled excitation voltage signal is an AC excitation voltage signal with a frequency in the second frequency range, or an AC excitation voltage signal with a frequency in the third frequency range. Wherein, any frequency in the first frequency range is greater than any frequency in the second frequency range, and any frequency in the third frequency range is greater than any frequency in the second frequency range.

[0011] Furthermore, the structural parameter values ​​of each PMUT array element are the same; The M PMUT array elements are arranged on the first substrate according to a first preset layout to obtain the PMUT array.

[0012] Furthermore, the M PMUT array elements include A first PMUT array elements with the target structure parameter terms having the first value, and B second PMUT array elements with the target structure parameter terms having the second value; wherein, A and B are both integers greater than 1 and A+B=M; A first PMUT array elements and B second PMUT array elements are arranged on the second substrate according to a second preset layout to obtain the PMUT array; A first PMUT array element A is used to receive the monitoring excitation voltage signal or the AC excitation voltage signal with a frequency in the third frequency range, and B second PMUT array elements are used to receive the AC excitation voltage signal with a frequency in the second frequency range.

[0013] Furthermore, the target structural parameter is the diameter; The diameter of the first PMUT element is smaller than the diameter of the second PMUT element.

[0014] To address the aforementioned technical problems, this invention also provides a control method for a read / write brain-computer interface integrated system, applied to the processing module of the read / write brain-computer interface integrated system as described above. The control method for the read / write brain-computer interface integrated system includes: When imaging monitoring is activated, a monitoring excitation voltage signal is output to the PMUT array in the integrated brain-computer interface system, so that the PMUT array vibrates based on the monitoring excitation voltage signal and emits a first ultrasound wave towards the target brain region. In this way, the first ultrasound wave is used to achieve acoustic acquisition of blood flow characteristic information of the target brain region in order to receive the corresponding first ultrasound echo and generate vibration based on the first ultrasound echo. The PMUT array receives a first electrical signal fed back based on the vibration generated by the first ultrasound echo, so as to reconstruct a functional ultrasound blood flow image of the target brain region based on the first electrical signal. The functional ultrasound blood flow images are decoded and analyzed to extract target feature parameters; When the intervention is activated based on the target characteristic parameters, the modulation excitation voltage signal is output to the PMUT array so that the PMUT array vibrates based on the modulation excitation voltage signal and emits a second ultrasound wave to the target brain region to regulate the neural activity of the target brain region through acoustic stimulation.

[0015] Furthermore, after outputting the controlled excitation voltage signal to the PMUT array, the method further includes: Reactivate imaging monitoring to determine whether to continue regulatory intervention based on the target characteristic parameters determined by imaging monitoring; If so, the control excitation voltage signal is corrected to output the corrected control excitation voltage signal to the PMUT array.

[0016] Furthermore, determining the activation of regulatory intervention based on the target characteristic parameters includes: Determine whether the target feature parameter has reached the corresponding preset threshold; If so, then regulatory intervention should be initiated.

[0017] The beneficial effects of this invention are as follows: This application provides a readable and writable brain-computer interface integrated system and its control method. The system includes a processing module and a PMUT array based on M PMUT elements. The PMUT array is positioned at a target location inside the brain and is connected to the processing module. The PMUT array is used to generate vibrations based on received monitoring excitation voltage signals to emit a first ultrasound wave towards the target brain region, thereby achieving acoustic acquisition of blood flow characteristic information of the target brain region through the first ultrasound wave to receive the corresponding first ultrasound echo, and generating vibrations based on the first ultrasound echo to feed back a first electrical signal to the processing module; it also generates vibrations based on received modulation excitation voltage signals to emit a second ultrasound wave towards the target brain region to regulate neural activity in the target brain region through acoustic stimulation. The processing module is used to output a monitoring excitation voltage signal to the PMUT array when imaging monitoring is activated, and to receive the first electrical signal to reconstruct a functional ultrasound blood flow image of the target brain region based on the first electrical signal; it decodes and analyzes the functional ultrasound blood flow image to extract target feature parameters, and when it is determined to activate modulation intervention based on the target feature parameters, it outputs a modulation excitation voltage signal to the PMUT array. As can be seen, this scheme constructs a single-modal imaging and control integrated closed-loop system of acoustic monitoring and acoustic modulation. Compared with the electro-acoustic closed-loop control scheme in related technologies, this scheme can fundamentally avoid the artifact interference caused by the mechanical effects of ultrasound on the EEG electrodes, ensuring the purity of the first electrical signal fed back by imaging monitoring. Moreover, based on the same PMUT array, imaging monitoring and control intervention of the target brain region can be achieved. Compared with the separate settings in related technologies, it can completely eliminate the alignment error in physical space and improve the accuracy of system imaging and control. In addition, the PMUT array elements have low power consumption characteristics, reducing the heat generated during operation, making it more suitable for long-term stable operation in the living brain. It is evident that the system is smaller in size, highly integrated, and conducive to clinical implantation and wear, thus facilitating practical applications.

[0018] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application, it can be implemented according to the contents of the specification. In order to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 A schematic diagram of the structure of an integrated brain-computer interface system for reading and writing provided by the present invention; Figure 2A schematic diagram of a read / write brain-computer interface integrated system supporting board-level connection settings provided by the present invention; Figure 3 This invention provides a schematic diagram of a read / write brain-computer interface integrated system that supports a single-chip high-integration configuration. Figure 4 A schematic diagram of the dual-frequency characteristics of a PMUT array element provided by the present invention; Figure 5 This invention provides a schematic diagram of the staggered arrangement of PMUT array elements; Figure 6 This invention provides a schematic diagram of the coaxial ring arrangement of PMUT array elements; Figure 7 This invention provides a schematic diagram of the block-based arrangement of each PMUT element region; Figure 8 The flowchart shows a control method for a read / write brain-computer interface integrated system provided by the present invention. Detailed Implementation

[0020] The core of this invention is to provide an integrated brain-computer interface system and its control method that can read and write. It constructs a single-modal imaging and control integrated closed-loop system of acoustic monitoring and acoustic modulation. Based on the PMUT array, it realizes imaging monitoring and control intervention of target brain regions. The system has higher imaging and control accuracy and lower power consumption.

[0021] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0022] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, in this application, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects have an "or" relationship.

[0023] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of an integrated brain-computer interface system for reading and writing provided by the present invention.

[0024] This integrated brain-computer interface system includes a processing module 1 and a PMUT array 2 based on M PMUT array elements; M is an integer greater than 1. PMUT array 2 is positioned at the target location inside brain 3 and is also connected to processing module 1. It is used to generate vibration based on the received monitoring excitation voltage signal to emit a first ultrasound wave to the target brain region, thereby achieving acoustic acquisition of blood flow characteristic information of the target brain region through the first ultrasound wave to receive the corresponding first ultrasound echo, and generating vibration based on the first ultrasound echo to feed back a first electrical signal to processing module 1; it also generates vibration based on the received modulation excitation voltage signal to emit a second ultrasound wave to the target brain region, so as to regulate the neural activity of the target brain region through acoustic stimulation. The processing module 1 is used to output a monitoring excitation voltage signal to the PMUT array 2 when imaging monitoring is turned on, and to receive a first electrical signal so as to reconstruct the functional ultrasound blood flow image of the target brain region based on the first electrical signal; to decode and analyze the functional ultrasound blood flow image to extract target feature parameters; and to output a modulation excitation voltage signal to the PMUT array 2 when it is determined to turn on the modulation intervention based on the target feature parameters.

[0025] This embodiment provides a closed-loop system setup for a long-term readable and writable brain-computer interface, capable of reliably achieving imaging monitoring and regulatory intervention. The system offers high flexibility in hardware configuration, supporting setups ranging from PCB board level to single-chip high integration. Specifically, the system supports board-level connection configurations, such as... Figure 2 As shown, at this point, only PMUT array 2 (Piezoelectric Micromachined Ultrasonic Transducers) is positioned at the target location inside brain 3; alternatively, the system can also support a single-chip highly integrated configuration, such as... Figure 3 As shown, at this time, the target chip 7 is integrated by the PMUT array 2 and the CMOS circuit 6. The target chip 7 is set at the target deployment position inside the brain 3, which will be described in detail in subsequent embodiments and will not be repeated here.

[0026] The PMUT array 2 or the integrated target chip 7 can be invasively or semi-invasively placed at the target location inside the brain 3 to achieve imaging monitoring and regulatory intervention. The invasive method requires penetrating the physical barriers of the skull and scalp, while the semi-invasive method requires minimally invasive surgery to implant the PMUT array 2 or target chip 7 into the skull and outside the cortex of the brain 3. The target placement location is chosen to facilitate the PMUT array 2's transmission of ultrasound waves to the target brain region and the reception of echoes; the specific location can be flexibly determined according to the location of the target brain region to be monitored, and no particular limitation is made here. It should also be noted that, as an application extension of the system provided in this application, the integrated brain-computer interface system can also be placed entirely outside the brain 3 in a non-invasive manner. In this case, the system is only used for regulatory intervention, and because the system is placed outside the body, no imaging monitoring is performed.

[0027] Specifically, a PMUT array element is an ultrasonic sensor fabricated using MEMS (Micro Electro Mechanical Systems) technology. Its core principle is to generate sound wave emission using the inverse piezoelectric effect of a piezoelectric thin film and receive the echo using the direct piezoelectric effect. More specifically, when an AC voltage is applied between the top and bottom electrodes of the PMUT array element, the piezoelectric thin film generates lateral strain, causing the suspended micro-thin film structure to bend and vibrate, thereby emitting ultrasonic waves into the medium. Conversely, the received sound wave pressure causes the thin film to deform, corresponding to the output electrical signal. This application utilizes the above characteristics of the PMUT array element to set up a PMUT array 2 based on M PMUT array elements, so as to realize imaging monitoring and regulatory intervention of a target brain region based on a single PMUT array. It is understood that multiple PMUT arrays 2 can also be set in the system, each PMUT array 2 is used for imaging monitoring and regulatory intervention of a target brain region location, without any special limitation here.

[0028] More specifically, PMUT array elements possess dual-frequency characteristics, meaning that in addition to the lowest-frequency fundamental vibration mode (i.e., the (0,1) mode), they also possess higher-frequency higher-order vibration modes, such as the (0,2) mode and the (1,1) mode; please refer to... Figure 4 , Figure 4 This invention provides a schematic diagram of the dual-frequency characteristics of a PMUT array element, where the vertical axis represents the normalized vibration displacement and the horizontal axis represents the vibration frequency. It can be seen that the PMUT array element exhibits two resonance peaks: the first resonance frequency is a low-frequency 2.9MHz, and the second resonance frequency is a high-frequency 11.8MHz. Figure 4 As shown.

[0029] Corresponding to imaging monitoring, based on functional ultrasound imaging (fUS), the instantaneous changes in local cerebral blood volume caused by neural activity in the target brain region are quantitatively characterized through the propagation of ultrasound waves, thereby achieving monitoring and imaging of the target brain region. Specifically, when imaging monitoring is activated, the processing module 1 outputs a monitoring excitation voltage signal to the PMUT array 2. After the monitoring excitation voltage signal is applied to the PMUT array 2, it causes the PMUT array 2 to vibrate and emit a first ultrasound wave towards the target brain region. This allows for acoustic acquisition of blood flow characteristic information of the target brain region through the first ultrasound wave, and the first ultrasound echo is reflected. The PMUT array 2 vibrates based on the first ultrasound echo and feeds back a first electrical signal to the processing module 1. When the processing module 1 receives the first electrical signal, it reconstructs the functional ultrasound blood flow image of the target brain region based on the first electrical signal. It should be noted that the monitoring excitation voltage signal here is an AC excitation voltage signal with a frequency within the first frequency range, so that the monitoring excitation voltage signal is essentially a high-frequency AC voltage signal, thereby driving the PMUT array 2 to vibrate, capturing hemodynamic changes at the millisecond to hundreds of millisecond levels, and ultimately achieving micron-level high spatial resolution imaging of blood flow. Furthermore, since ultrasound is essentially a mechanical wave, it is not affected by electromagnetic interference. For example, the first frequency range here can be 10 MHz - 20 MHz.

[0030] Corresponding to the regulatory intervention, based on LIFU technology (Low-Intensity Focused Ultrasound), the mechanically sensitive ion channels of neurons are activated through the force, thermal, and cavitation effects of sound waves, thereby achieving the regulation of neural activity in the target brain region. Specifically, the processing module 1 decodes and analyzes functional ultrasound blood flow images to extract target feature parameters, such as local cerebral blood volume, instantaneous rate of change of cerebral blood volume, and blood flow velocity offset. When the regulatory intervention is activated based on the target feature parameters, a regulatory excitation voltage signal is output. After this regulatory excitation voltage signal is applied to the PMUT array 2, it causes the PMUT array 2 to vibrate and emit a second ultrasound wave towards the target brain region, thereby regulating the neural activity of the target brain region through acoustic stimulation. It should be noted that the modulation excitation voltage signal here can be an AC excitation voltage signal with a frequency within the second frequency range, so that the modulation excitation voltage signal is essentially a low-frequency AC voltage signal, in order to ensure the penetration depth and generate sufficient mechanical effect. The modulation excitation voltage signal drives the PMUT array 2 to vibrate, focusing energy on the target brain region, realizing precise modulation of the deep target brain region at the micron to millimeter level resolution. Moreover, ultrasound modulation, as a purely physical intervention method, has higher biological safety. For example, the second frequency range can be 500kHz-3MHz; or, the modulation excitation voltage signal can also be an AC excitation voltage signal with a frequency within the third frequency range, as described in the following embodiments, which will not be repeated here.

[0031] It is understood that the processing module 1 can perform the above-mentioned imaging monitoring according to specific monitoring needs, or continuously perform the above-mentioned imaging monitoring according to a preset monitoring cycle; determine whether to start the control intervention based on the target feature parameters; after the control intervention ends, the imaging monitoring can be restarted to determine the effect of this control, and then determine the subsequent processing steps, i.e., continue the control or maintain the monitoring; in addition, when it is determined that the control intervention is not to be started based on the target feature parameters, the imaging monitoring can be maintained, or the imaging monitoring can be started when an indication signal indicating that the imaging monitoring is started is received.

[0032] It should be noted that the reason why PMUT array 2 is used in this application instead of traditional piezoelectric transducers (such as piezoelectric ceramics) for imaging monitoring and intervention of the target brain region is that the resonant frequency of traditional piezoelectric transducers is determined by the thickness of the ceramic sheet, making it difficult to simultaneously meet the needs of high-frequency monitoring and imaging and low-frequency intervention. In addition, traditional piezoelectric transducers are large in size, which is not conducive to integration, and they are usually driven by 100 volts, resulting in high power consumption, which is difficult to meet the miniaturization and low power consumption requirements of fully implantable closed-loop brain-computer interfaces. In contrast, PMUT array 2 in this application is more conducive to integration, has low power consumption characteristics, and is more conducive to practical applications.

[0033] In summary, this application provides a readable and writable brain-computer interface integrated system. This scheme constructs a single-modal imaging and control integrated closed-loop system of acoustic monitoring and acoustic modulation. Compared with the electro-acoustic closed-loop control scheme in related technologies, this scheme can fundamentally avoid the artifact interference caused by the mechanical effects of ultrasound on the EEG electrodes, ensuring the purity of the first electrical signal feedback from imaging monitoring. Moreover, based on the same PMUT array 2, imaging monitoring and control intervention of the target brain region can be achieved. Compared with the separate settings in related technologies, it can completely eliminate the alignment error in physical space, solve the spatial offset of the imaging and control corresponding areas, and improve the accuracy of system imaging and control. In addition, the PMUT array elements have low power consumption characteristics, reducing the heat generated during operation, making it more suitable for long-term stable operation in a living brain 3. It can be seen that the system is smaller in size, highly integrated, and conducive to clinical implantation and wear, which is beneficial to practical applications.

[0034] Based on the above embodiments: In some embodiments, the processing module 1 includes a host control module 5 disposed outside the brain 3, a transmitting circuit 41 and a receiving circuit 42 disposed on the PCB board 4; Each PMUT array element is connected to the transmitting circuit 41 and the receiving circuit 42 respectively, and the upper control module 5 is connected to the transmitting circuit 41 and the receiving circuit 42 respectively.

[0035] In this embodiment, a system setup scheme supporting PCB board-level connection settings is provided. Specifically, each PMUT element can be set in the target deployment position inside the brain 3 in an invasive or semi-invasive manner. Each PMUT element is also connected to the output terminal of the transmitting circuit 41 via an electrical line, and each PMUT element is also connected to the input terminal of the receiving circuit 42 via an electrical line. The input terminal of the transmitting circuit 41 is connected to the output terminal of the upper control module 5, and the output terminal of the receiving circuit 42 is connected to the input terminal of the upper control module 5.

[0036] The host control module 5 here can be various computer processing devices, such as a host computer. The host control module 5 outputs the monitoring excitation voltage signal or the regulation excitation voltage signal through the transmitting circuit 41, and receives the first electrical signal through the receiving circuit 42 for subsequent processing. The transmitting circuit 41 can be a dual-mode driver or other drivers capable of high-frequency imaging drive and low-frequency regulation drive, and the receiving circuit 42 can be various modules capable of signal acquisition, without any particular limitation.

[0037] In some embodiments, the processing module 1 includes a host control module 5 and a CMOS circuit 6; The upper control module 5 is connected to the PMUT array 2 via the CMOS circuit 6, and the upper control module 5 is located outside the brain 3; The CMOS circuit 6 and the PMUT array 2 are integrated on the same target chip 7 so that the target chip 7 can be placed at the target deployment location inside the brain 3.

[0038] In this embodiment, a system setup scheme supporting high integration of a single chip is provided. Specifically, the upper control module is located outside the brain 3. Based on MEMS technology, the CMOS circuit 6 and the PMUT array 2 are integrated into the same target chip 7. The target chip 7 is set in the target placement position inside the brain 3 in an invasive or semi-invasive manner. Combined with the low power consumption characteristics of the PMUT array 2, the system is conducive to adapting to long-term full implantation application scenarios, such as realizing cranial embedding or subdural full implantation.

[0039] The CMOS circuit 6 may include multiple dual-mode drive transceiver branches, each of which is electrically connected to a PMUT element in the array one-to-one. The host control module 5 can control each dual-mode drive transceiver branch under the CMOS circuit 6 and combine it with each PMUT element under the PMUT array 2 to realize imaging monitoring or control intervention. In addition, the host control module 5 here can be various computer processing devices, such as host computers.

[0040] In some embodiments, the monitored excitation voltage signal is an AC excitation voltage signal with a frequency located in a first frequency range; The excitation voltage signal is either an AC excitation voltage signal with a frequency in the second frequency range or an AC excitation voltage signal with a frequency in the third frequency range. Among them, any frequency in the first frequency range is greater than any frequency in the second frequency range, and any frequency in the third frequency range is greater than any frequency in the second frequency range.

[0041] Specifically, by setting the excitation voltage signal as described above, high-resolution functional ultrasound imaging is facilitated, enabling precise capture of changes in blood flow in blood vessels. By setting the excitation voltage signal to an AC excitation voltage signal with a frequency within the second frequency range, precise regulation of deep brain regions is facilitated. By setting the excitation voltage signal to an AC excitation voltage signal with a frequency within the third frequency range, high-precision regulation of the three outermost layers of the brain is facilitated. It is evident that the above settings achieve a deep integration of imaging monitoring and regulatory intervention.

[0042] It should also be noted that the modulation excitation voltage signal is an AC excitation voltage signal with a frequency within the third frequency range, so that the modulation excitation voltage signal at this time is essentially a high-frequency AC voltage signal, in order to achieve high-precision modulation of the three layers of the brain; the third frequency range here is not specifically limited, and can be flexibly set according to the actual application needs.

[0043] In some embodiments, the structural parameter items of each PMUT element have the same value; M PMUT array elements are arranged on the first substrate according to the first preset layout to obtain PMUT array 2.

[0044] In this embodiment, as described above, based on the dual-frequency characteristics of the PMUT array element, the PMUT array 2 can be constructed from M identical single PMUT array elements. That is, the values ​​of all structural parameter items (such as diameter and thickness) of each PMUT array element are the same, so that each PMUT array element is identical. The M PMUT array elements are arranged on the first substrate according to the first preset arrangement to obtain the PMUT array 2. The first preset arrangement includes, but is not limited to, the equal spacing arrangement. The advantage of this setting is that the geometric dimensions of the PMUT array elements are uniform, the spacing is uniform, and it is conducive to effectively improving the fill factor of the entire PMUT array 2 and suppressing grating lobe artifacts.

[0045] In one alternative implementation, all PMUT array elements can work synchronously, or only a portion of the PMUT array elements can be selected to work, so that the selected array elements can simultaneously achieve imaging monitoring or simultaneous modulation intervention, which is conducive to achieving complete synchronous alignment of imaging and modulation in the brain region space; and the same PMUT array element setting ensures good consistency, significantly reduces crosstalk level, and the impedance and capacitance of the entire PMUT array 2 are unified, enabling time-division multiplexing of dual-frequency modes.

[0046] In another optional implementation, a metal block is provided at the center of J PMUT array elements under M PMUT array elements, so that the PMUT array element with the metal block is used to receive AC excitation voltage signal with frequency in the second frequency range, and the remaining PMUT array elements are used to receive the monitoring excitation voltage signal or AC excitation voltage signal with frequency in the third frequency range; wherein, 1 < J < M and J is an integer.

[0047] It should be noted that in this embodiment, the values ​​of all structural parameters of the M PMUT array elements are still the same; the metal block mentioned here is essentially a metal mass block. By placing the metal block at the center of the J PMUT array elements, the resonant frequency of these PMUT array elements can be significantly reduced, so that these PMUT array elements can be used to receive AC excitation voltage signals with frequencies in the second frequency range; the remaining PMUT array elements other than the J PMUT array elements are used to receive monitoring excitation voltage signals to achieve high-frequency imaging monitoring, or to receive AC excitation voltage signals with frequencies in the third frequency range to achieve high-precision control of the three layers of the brain.

[0048] In another alternative implementation, the top electrodes of the M PMUT array elements are configured such that K PMUT array elements are used to receive AC excitation voltage signals with frequencies in a second frequency range; wherein 1 < K < M and K is an integer; the remaining PMUT array elements are used to receive the monitoring excitation voltage signal or an AC excitation voltage signal with a frequency in a third frequency range.

[0049] It should be noted that in this embodiment, the values ​​of all structural parameters of the M PMUT array elements are still the same; by configuring the top electrodes of the M PMUT array elements, the resonant frequency of the corresponding PMUT array elements can be customized. Different shapes of the top electrodes or the same shape but different sizes can activate different vibration modes; for example, the top electrodes of the M PMUT array elements can be ring electrodes, then the top electrodes of the K PMUT array elements can be small-sized ring electrodes to receive AC excitation voltage signals with frequencies in the second frequency range; the top electrodes of the remaining PMUT array elements can be large-sized ring electrodes to receive monitoring excitation voltage signals to achieve high-frequency imaging monitoring, or to receive AC excitation voltage signals with frequencies in the third frequency range to achieve high-precision control of the three layers of the brain.

[0050] In some embodiments, the M PMUT array elements include A first PMUT array elements with target structure parameter items having a first value, and B second PMUT array elements with target structure parameter items having a second value; wherein, A and B are both integers greater than 1 and A+B=M; A first PMUT array elements and B second PMUT array elements are arranged on the second substrate according to the second preset layout to obtain PMUT array 2; A first PMUT array element A is used to receive the monitoring excitation voltage signal or the AC excitation voltage signal with a frequency in the third frequency range, and B second PMUT array element B is used to receive the AC excitation voltage signal with a frequency in the second frequency range.

[0051] Specifically, A first PMUT array element is used to receive monitoring excitation voltage signals to achieve high-frequency imaging monitoring, or to receive AC excitation voltage signals with frequencies in the third frequency range to achieve high-precision regulation of the three superficial layers of the brain; B second PMUT array element is used to receive AC excitation voltage signals with frequencies in the second frequency range to achieve precise regulation of deep brain regions.

[0052] More specifically, in some embodiments, the target structural parameter is the diameter; The diameter of the first PMUT element is smaller than the diameter of the second PMUT element.

[0053] It can be seen that by taking different values ​​for the target structural parameter of diameter, the first PMUT element with a smaller diameter is used to achieve high-frequency imaging monitoring or high-precision control of the three superficial layers of the brain; while the second PMUT element with a larger diameter is used to achieve precise control of deep brain regions.

[0054] Furthermore, the second preset layout method here includes, but is not limited to, staggered layout, coaxial ring layout, or area-divided layout. Please refer to [the relevant documentation]. Figure 5 , Figure 6 and Figure 7 , Figure 5 This is a schematic diagram of the staggered arrangement of PMUT array elements provided by the present invention. Figure 6 This invention provides a schematic diagram of the coaxial ring arrangement of PMUT array elements. Figure 7 This is a schematic diagram of a block-based arrangement of PMUT array elements provided by the present invention. The first PMUT element 21, with a larger diameter, can correspond to a frequency of 1.8 MHz, while the second PMUT element 22, with a smaller diameter, can correspond to a frequency of 13 MHz, thus realizing the multi-frequency characteristics of the PMUT array 2.

[0055] Please refer to Figure 8 , Figure 8 The flowchart shows a control method for a read / write brain-computer interface integrated system provided by the present invention.

[0056] The control method for the read / write brain-computer interface integrated system is applied to the processing module 1 in the read / write brain-computer interface integrated system as described above. The control method for the read / write brain-computer interface integrated system includes: S11: When imaging monitoring is enabled, a monitoring excitation voltage signal is output to the PMUT array 2 in the integrated brain-computer interface system so that the PMUT array 2 vibrates based on the monitoring excitation voltage signal and emits a first ultrasound wave to the target brain region. In this way, the first ultrasound wave is used to achieve acoustic acquisition of blood flow characteristic information of the target brain region so as to receive the corresponding first ultrasound echo and generate vibration based on the first ultrasound echo. S12: Receive the first electrical signal fed back by the PMUT array 2 based on the vibration generated by the first ultrasound echo, so as to reconstruct the functional ultrasound blood flow image of the target brain region based on the first electrical signal; S13: Decode and analyze functional ultrasound blood flow images to extract target feature parameters; S14: When the control intervention is activated based on the target characteristic parameters, a control excitation voltage signal is output to the PMUT array 2 so that the PMUT array 2 can generate vibration based on the control excitation voltage signal and emit a second ultrasound wave to the target brain region to regulate the neural activity of the target brain region through acoustic stimulation.

[0057] For a description of the control method of the readable and writable brain-computer interface integrated system provided in this application, please refer to the above-described embodiment of the readable and writable brain-computer interface integrated system, which will not be repeated here.

[0058] In some embodiments, after outputting the modulated excitation voltage signal to the PMUT array 2, the method further includes: Reactivate imaging monitoring to determine whether to continue regulatory intervention based on the target characteristic parameters determined by imaging monitoring; If so, the control excitation voltage signal is corrected to output the corrected control excitation voltage signal to the PMUT array 2.

[0059] In this embodiment, after one modulation intervention, the system immediately switches back to the imaging monitoring stage. Based on the new target feature parameters determined by the imaging monitoring, it is determined whether to continue the modulation intervention. For example, the differences between functional ultrasound blood flow images before and after modulation can be compared. Specifically, the effect of neuromodulation can be quantitatively evaluated based on the differences between the target feature parameters. If it is determined to continue the modulation intervention, the parameters of the modulation excitation voltage signal can be corrected, such as the sound pressure intensity, duty cycle, and focusing depth, so as to output the corrected modulation excitation voltage signal to the PMUT array 2.

[0060] In some embodiments, determining to initiate regulatory intervention based on target characteristic parameters includes: Determine whether the target feature parameters have reached the corresponding preset threshold; If so, then regulatory intervention should be initiated.

[0061] Specifically, the target feature parameters can be local cerebral blood volume, instantaneous rate of change of cerebral blood volume, blood flow velocity offset, etc. When the target feature parameters are determined to reach the corresponding preset threshold, the regulatory intervention is activated. The preset threshold here corresponds to a specific functional area activation mode, which can be set according to the actual application needs. No special limit is placed on its value here.

[0062] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section. Relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0063] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A readable and writable brain-computer interface integrated system, characterized in that, It includes a processing module and a PMUT array based on M PMUT array elements; M is an integer greater than 1; The PMUT array is positioned at a target location inside the brain and is also connected to the processing module. It is used to generate vibrations based on received monitoring excitation voltage signals to emit a first ultrasound wave towards the target brain region. This first ultrasound wave enables acoustic acquisition of blood flow characteristics in the target brain region to receive the corresponding first ultrasound echo. Based on the first ultrasound echo, it generates vibrations to feed back a first electrical signal to the processing module. It also generates vibrations based on received modulation excitation voltage signals to emit a second ultrasound wave towards the target brain region, thereby modulating neural activity in the target brain region through acoustic stimulation. The processing module is used to output the monitoring excitation voltage signal to the PMUT array when imaging monitoring is enabled, and to receive the first electrical signal so as to reconstruct the functional ultrasound blood flow image of the target brain region based on the first electrical signal; to decode and analyze the functional ultrasound blood flow image to extract target feature parameters; and to output the modulation excitation voltage signal to the PMUT array when it is determined to enable modulation intervention based on the target feature parameters.

2. The readable and writable brain-computer interface integrated system as described in claim 1, characterized in that, The processing module includes a higher-level control module located outside the brain, a transmitting circuit and a receiving circuit deployed on a PCB board; Each PMUT array element is connected to the transmitting circuit and the receiving circuit respectively, and the upper-level control module is connected to the transmitting circuit and the receiving circuit respectively.

3. The readable and writable brain-computer interface integrated system as described in claim 1, characterized in that, The processing module includes a host control module and a CMOS circuit. The upper-level control module is connected to the PMUT array through the CMOS circuit, and the upper-level control module is located outside the brain; The CMOS circuitry and the PMUT array are integrated into the same target chip so that the target chip can be positioned at a target location inside the brain.

4. The readable and writable brain-computer interface integrated system as described in claim 1, characterized in that, The monitoring excitation voltage signal is an AC excitation voltage signal with a frequency within the first frequency range; The controlled excitation voltage signal is an AC excitation voltage signal with a frequency in the second frequency range, or an AC excitation voltage signal with a frequency in the third frequency range. Wherein, any frequency in the first frequency range is greater than any frequency in the second frequency range, and any frequency in the third frequency range is greater than any frequency in the second frequency range.

5. The readable and writable brain-computer interface integrated system as described in any one of claims 1 to 4, characterized in that, The structural parameter values ​​of each PMUT array element are the same; The M PMUT array elements are arranged on the first substrate according to a first preset layout to obtain the PMUT array.

6. The readable and writable brain-computer interface integrated system as described in any one of claims 1 to 4, characterized in that, The M PMUT array elements include A first PMUT array elements with the target structure parameter having the first value, and B second PMUT array elements with the target structure parameter having the second value; wherein, A and B are both integers greater than 1 and A+B=M; A first PMUT array elements and B second PMUT array elements are arranged on the second substrate according to a second preset layout to obtain the PMUT array; A first PMUT array element A is used to receive the monitoring excitation voltage signal or the AC excitation voltage signal with a frequency in the third frequency range, and B second PMUT array elements are used to receive the AC excitation voltage signal with a frequency in the second frequency range.

7. The readable and writable brain-computer interface integrated system as described in claim 6, characterized in that, The target structural parameter is the diameter; The diameter of the first PMUT element is smaller than the diameter of the second PMUT element.

8. A control method for a read / write brain-computer interface integrated system, characterized in that, A processing module applied to a read / write brain-computer interface integrated system as described in any one of claims 1 to 7, wherein the control method of the read / write brain-computer interface integrated system comprises: When imaging monitoring is activated, a monitoring excitation voltage signal is output to the PMUT array in the integrated brain-computer interface system, so that the PMUT array vibrates based on the monitoring excitation voltage signal and emits a first ultrasound wave towards the target brain region. In this way, the first ultrasound wave is used to achieve acoustic acquisition of blood flow characteristic information of the target brain region in order to receive the corresponding first ultrasound echo and generate vibration based on the first ultrasound echo. The PMUT array receives a first electrical signal fed back based on the vibration generated by the first ultrasound echo, so as to reconstruct a functional ultrasound blood flow image of the target brain region based on the first electrical signal. The functional ultrasound blood flow images are decoded and analyzed to extract target feature parameters; When the intervention is activated based on the target characteristic parameters, the modulation excitation voltage signal is output to the PMUT array so that the PMUT array vibrates based on the modulation excitation voltage signal and emits a second ultrasound wave to the target brain region to regulate the neural activity of the target brain region through acoustic stimulation.

9. The control method for the readable and writable brain-computer interface integrated system as described in claim 8, characterized in that, After outputting the controlled excitation voltage signal to the PMUT array, the method further includes: Reactivate imaging monitoring to determine whether to continue regulatory intervention based on the target characteristic parameters determined by imaging monitoring; If so, the control excitation voltage signal is corrected to output the corrected control excitation voltage signal to the PMUT array.

10. The control method for the readable and writable brain-computer interface integrated system as described in claim 8, characterized in that, Determining to initiate regulatory intervention based on the target characteristic parameters includes: Determine whether the target feature parameter has reached the corresponding preset threshold; If so, then regulatory intervention should be initiated.

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