Transcranial electrical stimulation equipment

Abstract

The invention provides transcranial electrical stimulation equipment, and particularly relates to the technical field of brain-computer interfaces, and the equipment comprises an electrical stimulation electrode array which is used for carrying out transcranial electrical stimulation and electroencephalogram signal collection on a target stimulation object; the electrical stimulation electrode array comprises a plurality of electrodes, and each electrode is provided with an electrode contact; each electrode contact is covered with an interface modification layer, the interface modification layer comprises a first hydrogel layer and a second hydrogel layer which are stacked in sequence, the first hydrogel layer is attached to the electrode contact, and the second hydrogel layer is used for making contact with the target stimulation object; the modulus of the first hydrogel layer is higher than that of the second hydrogel layer; the electrical stimulation control element is connected with the electrical stimulation electrode array and used for controlling current output of the electrical stimulation electrode array according to the electroencephalogram signals collected by the electrical stimulation electrode array. The quality and reliability of the electroencephalogram signals are improved.

Description

Technical Field

[0001] This application relates to the field of brain-computer interface technology, and in particular to a transcranial electrical stimulation device. Background Technology

[0002] Transcranial electrical stimulation (tES), as a non-invasive brain stimulation method, has received widespread attention in recent years. It modulates neural activity in the cerebral cortex by delivering weak electrical currents through electrodes placed on the scalp. Meanwhile, the acquisition and analysis of electroencephalogram (EEG) signals are crucial for understanding brain function and evaluating the effectiveness of electrical stimulation.

[0003] With the growing demand for brain-computer interface technology and personalized medicine, integrated devices combining transcranial electrical stimulation (TCS) and electroencephalogram (EEG) signal acquisition have emerged. These devices not only provide precise electrical stimulation but also monitor changes in brain activity during stimulation in real time, offering valuable feedback for scientific research and clinical practice. However, in practical applications, the EEG signals acquired by these integrated systems face a series of signal transmission quality issues.

[0004] Specifically, due to the attenuation of electrical signals by tissues such as the scalp and skull, as well as the presence of external electromagnetic interference, the raw EEG signals collected from the brain surface are often very weak and easily contaminated by noise. Furthermore, when electrical stimulation and EEG signal acquisition are performed simultaneously, the stimulation current may introduce additional artifacts, further affecting the quality and reliability of the data. These issues limit our depth of understanding of brain response patterns and pose challenges to subsequent processing algorithms based on EEG signal analysis. Summary of the Invention

[0005] To address at least one of the shortcomings of the prior art, this application provides a transcranial electrical stimulation device, comprising:

[0006] An electrical stimulation electrode array is used for transcranial electrical stimulation and electroencephalogram (EEG) signal acquisition on a target object. The array includes multiple electrodes, each with an electrode contact. Each electrode contact is covered with an interface modification layer, which comprises a first hydrogel layer and a second hydrogel layer stacked sequentially. The first hydrogel layer is attached to the electrode contact, and the second hydrogel layer is used to contact the target object. The modulus of the first hydrogel layer is higher than that of the second hydrogel layer.

[0007] An electrical stimulation control element connected to the electrical stimulation electrode array is used to control the current output of the electrical stimulation electrode array according to the electroencephalogram (EEG) signals collected by the electrical stimulation electrode array.

[0008] Optionally, the modulus of the first hydrogel layer is higher than a first preset threshold, the modulus of the second hydrogel layer is lower than a second preset threshold, and the first preset threshold is greater than or equal to the second preset threshold.

[0009] Optionally, a liquid metal layer is disposed between the first hydrogel layer and the second hydrogel layer.

[0010] Optionally, the interface modification layer encloses and forms an electrode groove, the first hydrogel layer constitutes the inner wall of the electrode groove, the second hydrogel layer constitutes the outer wall of the electrode groove, and the electrode contact is embedded in the electrode groove.

[0011] Optionally, the electrode is made of a tungsten-copper alloy.

[0012] Optionally, the transcranial electrical stimulation device further includes an array of digital filters, and the electrical stimulation control element is connected to the electrical stimulation electrode array through the array of digital filters to form an electroencephalogram (EEG) signal acquisition path.

[0013] Optionally, the EEG signal acquisition path includes a sub-path corresponding to each electrode, the array digital filter includes digital filters corresponding one-to-one with the plurality of electrodes, and the electrical stimulation control element is connected to the corresponding electrodes in the electrical stimulation electrode array through the plurality of digital filters to form a sub-path corresponding to each electrode.

[0014] Optionally, a signal amplification element is provided between the array-type digital filter and the electrical stimulation electrode array, the signal amplification element being used to amplify the electroencephalogram (EEG) signals acquired by the electrical stimulation electrode array.

[0015] Optionally, the signal input terminal of the signal amplification element is provided with a gain controller.

[0016] Optionally, the signal output terminal of the signal amplification element is provided with an analog-to-digital converter.

[0017] By adopting the above technical solution, this application has the following beneficial effects:

[0018] This application provides a transcranial electrical stimulation device, including an array of electrical stimulation electrodes and an electrical stimulation control element connected to the array. The array includes multiple electrodes, each with an electrode contact. By providing an interface modification layer, including a first hydrogel layer and a second hydrogel layer, on each electrode contact, this structure significantly improves the contact quality between the electrode and the scalp. The first hydrogel layer, due to its high modulus, provides stable support, while the second hydrogel layer, with its lower modulus, ensures good adhesion to the skin, thereby reducing external interference and motion artifacts, improving the fidelity of the acquired EEG signals, and making the acquired EEG signals purer, providing high-quality basic data for subsequent data analysis. Using a soft and highly elastic hydrogel material as the interface layer in direct contact with the skin not only ensures good electrical connection but also increases comfort during wear and reduces the risk of discomfort or skin damage that may occur with prolonged use. The electrical stimulation control element is used to dynamically adjust the current output of the electrical stimulation electrode array according to the actual acquired EEG signals, realizing personalized customization of stimulation parameters, ensuring the accuracy and safety of the transcranial electrical stimulation device during operation, and also enhancing the system's adaptability and flexibility to cope with the differences in brain response patterns among different individuals.

[0019] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. The same reference numerals usually represent the same components. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the transcranial electrical stimulation device provided in the embodiments of this application;

[0022] Figure 2 This is a schematic diagram of the electrode structure provided in the embodiments of this application;

[0023] Figure 3 This is a schematic diagram of the interface modification layer provided in the embodiments of this application;

[0024] Figure 4 This is a schematic diagram of the electrode groove provided in an embodiment of this application.

[0025] The following is supplementary explanation of the attached figures:

[0026] 1. Electrode; 2. Electrode contact; 3. Interface modification layer; 4. First hydrogel layer; 5. Liquid metal layer; 6. Second hydrogel layer; 7. Electrical stimulation control element; 8. Electrode groove; 9. Arrayed digital filter; 10. Current input circuit; 11. Electrical stimulation modulation circuit; 12. Solenoid valve. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0028] The term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of this application. In the description of this application, it should be understood that the terms "upper," "lower," "top," "bottom," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. 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 such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein.

[0029] refer to Figure 1 This application provides a transcranial electrical stimulation device, comprising:

[0030] An electrical stimulation electrode array is used for transcranial electrical stimulation and electroencephalogram (EEG) signal acquisition on a target subject. It allows the device to monitor and record brain activity simultaneously, providing real-time feedback. The electrical stimulation electrode array comprises multiple electrodes 1. These electrodes 1 are arranged in combination to form the electrical stimulation electrode array. The coordinated work between these electrodes 1 can generate complex stimulation patterns to adapt to different brain regions and neural networks. By configuring the layout of these electrodes 1, uniform stimulation of the cerebral cortex can be achieved while targeted stimulation of specific areas. This master-slave stimulation approach allows the device to flexibly adjust stimulation strategies to meet different needs.

[0031] Optionally, electrode 1 is made of tungsten-copper alloy. Tungsten-copper alloy is a composite metal material made by combining tungsten powder and copper powder (which has good plasticity and electrical conductivity) through hydrostatic pressing, high-temperature sintering, and refining. Due to its high copper content, tungsten-copper alloy inherits copper's excellent electrical and thermal conductivity, which is crucial for the efficiency and thermal management of electrode 1 during electrical stimulation. Tungsten-copper alloy remains stable at high temperatures, is not easily melted, and has high resistance to arc erosion, which is particularly important for electrode 1, which needs to operate under high pressure or high temperature conditions. The combination of tungsten's high hardness and copper's plasticity makes electrode 1 both robust and durable, suitable for maintaining performance during long-term or repeated use. Tungsten-copper alloy has a low coefficient of thermal expansion and good dimensional stability under temperature changes, which is crucial for maintaining the stability and consistency of electrode 1 in contact with the skin. Tungsten-copper alloy has good biocompatibility, suitable for contact with the human body, reducing the possibility of biological rejection reactions during long-term use. Tungsten-copper alloy can be processed into complex shapes and sizes to meet the specific needs of electrodes in different application scenarios. Therefore, tungsten-copper alloy, as the material of electrode 1, not only provides excellent electrical and thermal properties, but also ensures reliability and durability under long-term and high-pressure working conditions.

[0032] like Figure 2 As shown, each electrode 1 is provided with an electrode contact 2; each electrode contact 2 is covered with an interface modification layer 3. The electrode contact 2 is a metal contact used to transmit electrical stimulation signals and monitor electroencephalogram (EEG) signals. In transcranial electrical stimulation (TCS) devices, the electrode contact 2 is not only responsible for outputting an electrical stimulation current modulated separately by a control signal, but also serves as a feedback electrode to monitor the current when no current is output. The main function of the interface modification layer 3 is to improve the contact quality between the electrode 1 and the skin, thereby improving the efficiency and accuracy of signal transmission. In specific implementations, the interface modification layer 3 can be further functionalized through chemical or physical methods to enhance its adhesion to the skin and its electrical conductivity. For example, its surface properties can be improved by introducing specific functional groups onto the surface or by using plasma treatment.

[0033] like Figure 2As shown, the transcranial electrical stimulation device also includes a solenoid valve 12 disposed on each electrode 1. Each solenoid valve 12 is connected to the electrical stimulation control element 7. The solenoid valve 12 receives a second control signal from the electrical stimulation control element 7 and controls whether the electrode contact 2 of the corresponding electrode 1 acts on the target stimulation object based on the second control signal. Specifically, each electrode 1 is equipped with a corresponding solenoid valve 12 to achieve independent control of each stimulation point. In specific implementation, the solenoid valve 12 can adopt a miniature spring solenoid valve design, which can provide fast response and precise control. The miniature spring solenoid valve uses the elastic force of the spring to assist the opening and closing of the valve core, ensuring rapid valve switching and good sealing. A linear displacement sensor is integrated into the miniature spring solenoid valve to monitor the position of the valve core in real time, ensuring precise control of the solenoid valve 12. The electrical stimulation control element 7 adjusts the parameters of the second control signal according to the feedback signal of the linear displacement sensor to ensure the precise action of the solenoid valve 12. Specifically, in this embodiment, by setting an electromagnetic valve 12 on each electrode 1 and controlling the electromagnetic valve 12 with the electrical stimulation control element 7, it can be ensured that the electrical stimulation is accurately applied to the target area, prevent unnecessary stimulation of non-target areas, reduce potential side effects, and improve the safety of electrical stimulation; thus enabling the transcranial electrical stimulation device to provide a more flexible stimulation mode to adapt to the needs of different target stimulation subjects.

[0034] like Figure 3 As shown, the interface modification layer 3 includes a first hydrogel layer 4 and a second hydrogel layer 6 stacked sequentially. The first hydrogel layer 4 and the second hydrogel layer 6 are made of flexible polymer nanomaterials, such as polymeric hydrogels. These materials, due to their high water content and soft elasticity similar to biological tissues, exhibit good compatibility with surrounding tissues and cells. The modulus of the first hydrogel layer 4 is higher than that of the second hydrogel layer 6. The first hydrogel layer 4 adheres to the electrode contact 2, while the second hydrogel layer 6 is used to contact the target stimulation object. The first hydrogel layer 4 is dense, with small ion channels, possessing strong mechanical properties that maintain structural stability and provide solid support. In contrast, the second hydrogel layer 6 is relatively porous, possessing self-adhesion, strong deformability, and larger ion channels, enabling it to adhere tightly to the tissue surface, facilitating ion shuttle movement, significantly reducing interfacial impedance, and improving the quality of electrode signal transmission. The second hydrogel layer 6 ensures good adhesion to the skin, reducing external interference and motion artifacts, and improving the fidelity of EEG signals.

[0035] In specific implementation, the modulus of the first hydrogel layer 4 is higher than the first preset threshold, and the modulus of the second hydrogel layer 6 is lower than the second preset threshold. The first preset threshold is greater than or equal to the second preset threshold. For example, the value of the first preset threshold can be 1000 Pa, and the value of the second preset threshold can be 500 Pa. The setting of the interface modification layer 3 helps to reduce external interference and motion artifacts, and improve the fidelity of EEG signals.

[0036] Optionally, a liquid metal layer 5 is disposed between the first hydrogel layer 4 and the second hydrogel layer 6. Specifically, the liquid metal has excellent conductivity, providing a low-impedance conductive channel, resulting in less loss of electrical stimulation current and EEG signals during transmission and higher transmission efficiency. Due to the fluidity of the liquid metal, it can form a continuous conductive layer between the electrode contact 2 and the skin, avoiding current concentration or uneven distribution caused by uneven contact. This uniform current distribution helps reduce the risk of local overheating during stimulation, improving the safety of electrical stimulation, and also making the acquisition of EEG signals more stable and reliable. During EEG signal acquisition, external electromagnetic interference (such as power line interference, radio frequency signal interference, etc.) may generate noise in the EEG signals, affecting the quality and accuracy of the signals. The liquid metal layer 5 can block these external interference signals, reducing their impact on the EEG signals, thereby improving the signal-to-noise ratio and making the acquired EEG signals purer, providing higher-quality basic data for subsequent data analysis and processing. When electrical stimulation and EEG signal acquisition are performed simultaneously, the stimulation current may introduce additional artifacts, interfering with the accuracy of the EEG signals. The electromagnetic shielding effect of the liquid metal layer 5 reduces the generation of artifacts, ensuring the authenticity and reliability of EEG signals. Due to the fluidity and plasticity of the liquid metal, it can adapt to minute changes and irregularities on the skin surface, maintaining a tight interface. Even with movement of the target stimulus or slight electrode movement, the liquid metal layer 5 maintains good contact, reducing signal interruptions or distortions caused by poor contact, thus improving the stability and reliability of the device in practical applications.

[0037] Optional, such as Figure 4 As shown, the interface modification layer 3 encloses and forms the electrode groove 8. The first hydrogel layer 4 forms the inner wall of the electrode groove 8, and the second hydrogel layer 6 forms the outer wall of the electrode groove 8. The electrode contact 2 is embedded in the electrode groove 8. This provides a stable support structure while ensuring good contact between the electrode contact 2 and the skin. In specific implementations, the electrode groove 8 can be formed by injection molding or 3D printing technology to ensure precise fit between the electrode contact 2 and the electrode groove 8, guaranteeing the consistency of the shape and size of the electrode groove 8, thereby improving the reliability and repeatability of the product. To further improve the contact quality between the electrode contact 2 and the skin, its modulus and elasticity can be optimized by adjusting the formulation and crosslinking degree of the second hydrogel layer 6. For example, the modulus of the second hydrogel layer 6 can be adjusted by adding specific crosslinking agents or changing the concentration of polymers to achieve optimal performance. The design of the electrode groove 8 is not only suitable for transcranial electrical stimulation devices, but can also be extended to other devices that require precise electrical stimulation and signal acquisition, such as pacemakers and neuromuscular stimulators, and can be adjusted and optimized according to the needs of different applications.

[0038] The electrical stimulation control element 7, connected to the electrical stimulation electrode array, controls the current output of each electrode contact 2 based on the electroencephalogram (EEG) signals acquired by the array. The control element 7 analyzes the EEG signals in real time and adjusts the stimulation parameters accordingly to adapt to different individual brain activity patterns. The signal amplitude and frequency of electrode 1 can be dynamically modulated by the control element 7, enabling the device to adjust the current output of each electrode contact based on the real-time acquired EEG signals. This dynamic adjustment mechanism allows for personalized customization of stimulation parameters, ensuring the accuracy and safety of transcranial electrical stimulation. The control element 7 constructs a closed-loop feedback control system where real-time EEG data is used to adjust stimulation parameters to quickly respond to changes in brain activity and provide timely and precise stimulation.

[0039] Specifically, the electrical stimulation control element 7 is responsible for receiving and processing external instructions (such as doctor's operating instructions or preset programs). The electrical stimulation control element 7 includes a DAC (Digital-to-Analog Converter), a bandgap, a power management module, and other necessary control logic. The DAC converts digital signals into analog current signals, and the bandgap provides a stable reference voltage to ensure that the system remains stable under different operating conditions.

[0040] In its implementation, the electrical stimulation control element 7 integrates algorithms and software for analyzing electroencephalogram (EEG) signals and determining stimulation parameters. For example, it integrates machine learning algorithms to predict and adapt to dynamic changes in brain activity. The electrical stimulation control element 7 can not only process signals from the electrical stimulation electrode array but also integrate other modalities of neural monitoring equipment, such as functional magnetic resonance imaging (fMRI) or near-infrared spectroscopy, to provide more comprehensive information on brain activity. The electrical stimulation control element 7 should also include safety measures, such as current and voltage limits, as well as anomaly detection and automatic shutdown functions to prevent overstimulation and potential harm.

[0041] In practice, the electrical stimulation control element 7 is connected to the current input circuit 10. The current input circuit 10 is responsible for converting the external power supply into a stable DC or AC current suitable for transcranial electrical stimulation, providing the necessary power support for the stimulation. The current input circuit 10 may include components such as active filters and current-limiting resistors to protect the system from overload or other abnormal conditions. In addition, the current input circuit 10 may also include safety mechanisms, such as voltage and current limiting, and fault detection functions, to ensure the stability and safety of the system even under extreme conditions.

[0042] Specifically, in this embodiment, the electrical stimulation electrode array has both transcranial electrical stimulation and EEG signal acquisition functions. Furthermore, by setting an interface modification layer 3 on the electrode contact 2 of each electrode 1, a certain level of wearing comfort is ensured, achieving ultra-low interface impedance and high signal fidelity, which can meet the needs of deep electrical stimulation and brain function assessment. The electrical stimulation control element 7 constructs a closed-loop feedback control system, in which real-time data of EEG signals are used to adjust stimulation parameters to quickly respond to changes in brain activity and provide timely and accurate stimulation.

[0043] In one possible implementation, such as Figure 1 As shown, the transcranial electrical stimulation (ECG) device also includes an array of digital filters 9. The electrical stimulation control element 7 is connected to the electrical stimulation electrode array via the array of digital filters 9, forming an EEG signal acquisition path. Specifically, the EEG signal acquisition path includes a sub-path corresponding to each electrode 1. The array of digital filters 9 includes digital filters corresponding one-to-one with multiple electrodes 1. The electrical stimulation control element 7 is connected to the corresponding electrode 1 in the electrical stimulation electrode array via multiple digital filters, forming a sub-path corresponding to each electrode 1. Specifically, the digital filters are used to process the EEG signals acquired through the electrode contacts 2. During EEG signal acquisition, external electromagnetic interference and physiological noise (such as electromyography interference, electrooculography interference, etc.) may affect signal quality. The digital filters can effectively suppress these noises and improve the signal-to-noise ratio. The digital filters can help extract key features from the EEG signals, providing an accurate data foundation for subsequent data analysis and pattern recognition. In multi-channel EEG signal acquisition, the digital filters can ensure synchronous processing of signals from different channels, which helps to compare and analyze the activity patterns of different brain regions.

[0044] In practical implementation, digital filters can be configured to have specific frequency response characteristics to adapt to different EEG signal processing needs. For example, a high-pass filter can be designed to remove low-frequency power supply interference, or a band-pass filter can be designed to extract EEG signals in specific frequency bands. Digital filters can be programmable, allowing users to adjust filtering parameters as needed, enabling the device to adapt to different application scenarios and individual differences. Digital filters can integrate signal processing algorithms, such as adaptive filtering algorithms, to optimize filtering effects in real time and reduce the impact of environmental noise and artifacts. Array-type digital filters can be designed modularly for easy maintenance and upgrades; specifically, each digital filter acts as an independent module, allowing for individual operation when replacement or upgrades are needed.

[0045] Specifically, in this embodiment, the application of the array-type digital filter 9 can significantly improve the quality of EEG signals, reduce noise and artifacts, and make the acquired signals clearer and more accurate. Each electrode 1 is equipped with an independent digital filter, enabling the system to perform individual digital signal processing on the EEG signals acquired by each electrode 1, thereby enhancing the overall signal processing capability and improving signal quality and reliability.

[0046] In one possible implementation, a signal amplification element is disposed between the array-type digital filter 9 and the electrostimulation electrode array. This signal amplification element amplifies the EEG signals acquired by the electrostimulation electrode array. Specifically, EEG signals are inherently very weak, typically only a few microvolts or even lower. During signal transmission, especially after passing through electrodes and wires, the signal may further attenuate. The signal amplification element effectively amplifies these weak EEG signals, bringing them to the level range required for subsequent processing by the array-type digital filter 9. While amplifying the signal, the signal amplification element can also suppress noise to some extent. By selecting appropriate amplification circuit design and parameters, noise can be filtered out or suppressed while amplifying the signal, thereby improving the signal-to-noise ratio of the EEG signal. The signal amplification element and the array-type digital filter 9 work together to optimize the filtering effect. After the signal amplification element amplifies the signal to a suitable level, the array-type digital filter 9 can perform filtering more effectively, suppressing noise and artifacts and extracting useful signal components.

[0047] Specifically, the signal amplification element includes a gain controller. The gain controller adjusts the gain of the signal amplification element, thereby controlling the amplification factor of the EEG signal. Since the intensity of EEG signals may vary depending on the target stimulus, or the amplitude of the EEG signal may change under different experimental conditions, the gain controller can flexibly adjust the amplification level according to actual needs. For example, when the signal is weak, the gain can be increased to achieve a suitable amplitude for subsequent processing; while when the signal is strong, the gain can be decreased to avoid signal saturation or distortion. By appropriately setting the gain, the gain controller can optimize the quality of the EEG signal. During signal amplification, if the gain is too high, noise may be introduced, leading to signal distortion; while if the gain is too low, useful information in the signal may not be effectively extracted. The gain controller can select an appropriate gain value based on the signal characteristics and noise level, so that the amplified signal has a high signal-to-noise ratio and good dynamic range, providing a high-quality foundation for subsequent digital filtering and data analysis. The gain controller can also achieve personalized gain adjustment for different electrode channels. Since the EEG signals acquired by each electrode 1 in the electrical stimulation electrode array may differ, the gain controller can independently set the gain for each electrode channel to meet the specific needs of signal processing for different channels.

[0048] Specifically, signal amplification components also include analog-to-digital converters (ADCs). ADCs convert amplified analog EEG signals into digital signals. Through processes such as sampling and quantization, ADCs discretize continuous analog signals into digital signals, enabling subsequent digital filtering, feature extraction, and data analysis to be performed in the digital domain. This not only improves the accuracy and efficiency of signal processing but also facilitates further signal analysis and applications. The resolution of the ADC directly affects the accuracy of the digital signal. High-resolution ADCs can more accurately represent subtle changes in analog signals, retaining more detailed signal information. This is crucial for analyzing complex EEG signal characteristics, such as the frequency components and phase relationships of brain waves. High-precision digital signals help improve the accuracy of subsequent data analysis, thereby better revealing the patterns and mechanisms of brain activity.

[0049] Specifically, in the embodiments of this application, after the signal amplification element amplifies the signal to a suitable level, the array-type digital filter 9 can perform filtering more effectively, suppress noise and artifacts, and extract useful signal components, thereby making the entire signal processing link more efficient and accurate, and better meeting the signal processing requirements of transcranial electrical stimulation devices.

[0050] In summary, the transcranial electrical stimulation device of this application includes an electrical stimulation electrode array and an electrical stimulation control element connected to the electrical stimulation electrode array. The electrical stimulation electrode array includes multiple electrodes, each of which has an electrode contact. By providing an interface modification layer, including a first hydrogel layer and a second hydrogel layer, on each electrode contact, this structure significantly improves the contact quality between the electrode and the scalp. The first hydrogel layer, due to its high modulus, provides stable support, while the second hydrogel layer, with its lower modulus, ensures good adhesion to the skin, thereby reducing external interference and motion artifacts, improving the fidelity of the acquired EEG signals, and making the acquired EEG signals purer, providing high-quality basic data for subsequent data analysis. Using a soft and highly elastic hydrogel material as the interface layer in direct contact with the skin not only ensures good electrical connection but also increases comfort during wear and reduces the risk of discomfort or skin damage that may occur with prolonged use. The electrical stimulation control element is used to dynamically adjust the current output of the electrical stimulation electrode array according to the actual acquired EEG signals, realizing personalized customization of stimulation parameters, ensuring the accuracy and safety of the transcranial electrical stimulation device during operation, and also enhancing the system's adaptability and flexibility to cope with the differences in brain response patterns among different individuals.

[0051] In this application, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the connection within two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0052] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, while this specification describes specific embodiments, other embodiments are also within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in the order shown in different embodiments and still achieve the desired results. Additionally, the processes depicted in the drawings do not necessarily require a specific order or sequence of connections to achieve the desired results; in some implementations, parallel processing of multiple tasks is possible or may be advantageous.

[0053] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. The focus of each embodiment is to describe the differences from other embodiments.

[0054] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A transcranial electrical stimulation device, characterized in that, include: An electrical stimulation electrode array, wherein the electrical stimulation electrode array is used to perform transcranial electrical stimulation and acquire electroencephalogram (EEG) signals on a target stimulation object; The electrical stimulation electrode array includes multiple electrodes, each of which has an electrode contact. Each electrode contact is covered with an interface modification layer, which includes a first hydrogel layer and a second hydrogel layer stacked sequentially. The first hydrogel layer is attached to the electrode contact, and the second hydrogel layer is used to contact the target stimulation object. The modulus of the first hydrogel layer is higher than that of the second hydrogel layer. An electrical stimulation control element connected to the electrical stimulation electrode array is used to control the current output of the electrical stimulation electrode array according to the electroencephalogram (EEG) signals collected by the electrical stimulation electrode array.

2. The transcranial electrical stimulation device according to claim 1, characterized in that, The modulus of the first hydrogel layer is higher than the first preset threshold, the modulus of the second hydrogel layer is lower than the second preset threshold, and the first preset threshold is greater than or equal to the second preset threshold.

3. The transcranial electrical stimulation device according to claim 2, characterized in that, A liquid metal layer is disposed between the first hydrogel layer and the second hydrogel layer.

4. The transcranial electrical stimulation device according to any one of claims 1 to 3, characterized in that, The interface modification layer encloses and forms an electrode groove, the first hydrogel layer constitutes the inner wall of the electrode groove, the second hydrogel layer constitutes the outer wall of the electrode groove, and the electrode contact is embedded in the electrode groove.

5. The transcranial electrical stimulation device according to claim 4, characterized in that, The electrode is made of tungsten-copper alloy.

6. The transcranial electrical stimulation device according to claim 5, characterized in that, It also includes an array of digital filters, and the electrical stimulation control element is connected to the electrical stimulation electrode array through the array of digital filters to form an EEG signal acquisition path.

7. The transcranial electrical stimulation device according to claim 6, characterized in that, The EEG signal acquisition path includes a sub-path corresponding to each electrode, the array digital filter includes digital filters that correspond one-to-one with the plurality of electrodes, and the electrical stimulation control element is connected to the corresponding electrodes in the electrical stimulation electrode array through the plurality of digital filters to form a sub-path corresponding to each electrode.

8. The transcranial electrical stimulation device according to claim 5, characterized in that, A signal amplification element is provided between the array-type digital filter and the electrostimulation electrode array, and the signal amplification element is used to amplify the electroencephalogram (EEG) signals collected by the electrostimulation electrode array.

9. The transcranial electrical stimulation device according to claim 8, characterized in that, The signal input terminal of the signal amplification element is equipped with a gain controller.

10. The transcranial electrical stimulation device according to claim 9, characterized in that, The signal output terminal of the signal amplification element is equipped with an analog-to-digital converter.

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