CN115238745A - Generation method and system for analog acquisition of electroencephalogram signals - Google Patents

Generation method and system for analog acquisition of electroencephalogram signals Download PDF

Info

Publication number
CN115238745A
CN115238745A CN202210910794.XA CN202210910794A CN115238745A CN 115238745 A CN115238745 A CN 115238745A CN 202210910794 A CN202210910794 A CN 202210910794A CN 115238745 A CN115238745 A CN 115238745A
Authority
CN
China
Prior art keywords
signal
electroencephalogram
noise
noise signal
interest
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210910794.XA
Other languages
Chinese (zh)
Inventor
张家伟
陈超
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sichuan Neosource Biotektronics Ltd
Original Assignee
Sichuan Neosource Biotektronics Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sichuan Neosource Biotektronics Ltd filed Critical Sichuan Neosource Biotektronics Ltd
Priority to CN202210910794.XA priority Critical patent/CN115238745A/en
Publication of CN115238745A publication Critical patent/CN115238745A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/30Input circuits therefor
    • A61B5/307Input circuits therefor specially adapted for particular uses
    • A61B5/31Input circuits therefor specially adapted for particular uses for electroencephalography [EEG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/24Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/316Modalities, i.e. specific diagnostic methods
    • A61B5/369Electroencephalography [EEG]
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/72Signal processing specially adapted for physiological signals or for diagnostic purposes
    • A61B5/7203Signal processing specially adapted for physiological signals or for diagnostic purposes for noise prevention, reduction or removal

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • Veterinary Medicine (AREA)
  • Public Health (AREA)
  • Physics & Mathematics (AREA)
  • General Health & Medical Sciences (AREA)
  • Biophysics (AREA)
  • Pathology (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Medical Informatics (AREA)
  • Molecular Biology (AREA)
  • Signal Processing (AREA)
  • Psychiatry (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Artificial Intelligence (AREA)
  • Physiology (AREA)
  • Psychology (AREA)
  • Measurement And Recording Of Electrical Phenomena And Electrical Characteristics Of The Living Body (AREA)

Abstract

The embodiment of the specification provides a generation method and a system for simulating an acquired electroencephalogram signal, wherein the method comprises the following steps: acquiring an intermediate simulated electroencephalogram signal based on the first preset parameter interval and the basic signal; constructing a loss function based on the intermediate simulated electroencephalogram signal and the reference electroencephalogram signal; iteratively updating the first preset parameter interval based on the loss function until a preset condition is met, and obtaining a first parameter set; obtaining a noise-free simulated electroencephalogram signal based on the basic signal and the first parameter group; obtaining a target noise signal based on the initial noise signal and the second parameter group; and obtaining the target simulated acquisition electroencephalogram signal based on the simulated electroencephalogram signal, the target noise signal, the first weight and the second weight. The simulated brain electrical signal, the target noise signal and the target simulated collected brain electrical signal can be used as the noiseless brain electrical signal in the human body, the noise signal in the collected brain electrical signal and the collected brain electrical signal to participate in the analysis and research of the brain electrical signal.

Description

Generation method and system for analog acquisition of electroencephalogram signals
Description of the cases
The application is a divisional application of Chinese patent application 202210659471.8, which is filed on 13.06.13.2022 and is entitled "a method and a system for generating analog acquisition electroencephalogram signals".
Technical Field
The present disclosure relates to the field of analog electroencephalogram signals, and in particular, to a method and a system for generating analog acquisition electroencephalogram signals.
Background
With the progress of science and the rapid development of biomedical technology, biological signals are applied to research in various fields. For example, electroencephalogram signals can be used to aid in the diagnosis of sleep classification, epilepsy, and depression. However, the amplitude of the brain electrical signal is small, generally only tens to hundreds of microvolts, and the brain electrical signal is interfered by various noise signals in the acquisition process, and most commonly, some noise signals such as ocular artifacts and myoelectrical artifacts are generated. Meanwhile, when electroencephalogram signals of a human body are collected by the electroencephalogram collecting equipment, the electroencephalogram signals and noise signals can be influenced by various factors such as a brain functional area and electrode points in the transmission process when being transmitted to the electrode points in the electroencephalogram collecting equipment from the generation positions of the electroencephalogram signals and the noise signals, the electroencephalogram signals and the noise signals in the collected electroencephalogram signals which are finally collected by the electrode points are different from signals sent by the generation positions of the electroencephalogram signals, and therefore the electroencephalogram signals and the noise signals in the electroencephalogram signals are difficult to distinguish.
At present, a machine learning model can be utilized to carry out denoising processing on the acquired electroencephalogram signals, but due to the limitation of acquisition time and acquisition means, a large amount of training data required by model training is difficult to acquire.
Therefore, it is necessary to provide a method for generating an analog-collected electroencephalogram signal, which can determine the transfer relationship of the signal when the signal propagates in the brain, so that the generated analog-collected electroencephalogram signal is as close to the real collected electroencephalogram signal as possible, so as to obtain a large amount of training data required by model training, so that the trained denoising model has a better generalization effect, and the cost required for collecting the electroencephalogram signal of a human body can be reduced when the electroencephalogram signal is researched.
Disclosure of Invention
One or more embodiments of the present specification provide a method for generating a simulated acquired brain electrical signal, the method comprising: acquiring an intermediate simulated electroencephalogram signal based on the first preset parameter interval and the basic signal; constructing a loss function based on the intermediate simulated electroencephalogram signal and the reference electroencephalogram signal; iteratively updating the first preset parameter interval based on the loss function until a preset condition is met, and obtaining a first parameter set; obtaining a noise-free simulated electroencephalogram signal based on the basic signal and the first parameter group, wherein the simulated electroencephalogram signal is used as a noise-free electroencephalogram signal in a human body to participate in analysis and research of the electroencephalogram signal; obtaining a target noise signal based on the initial noise signal and the second parameter group, wherein the target noise signal is used as a noise signal in the collected electroencephalogram signal of the human body to participate in analysis and research of the electroencephalogram signal; acquiring a first weight of the simulated brain electrical signal and a second weight of the target noise signal; and obtaining a target simulation collection electroencephalogram signal based on the simulation electroencephalogram signal, the target noise signal, the first weight and the second weight, wherein the target simulation collection electroencephalogram signal is used as the collection electroencephalogram signal to participate in analysis and research of the electroencephalogram signal and reduce collection of a real electroencephalogram signal.
One or more embodiments of the present specification provide a generation system for simulating acquisition of an electroencephalogram signal, the system comprising: a first obtaining module to: obtaining an intermediate simulated electroencephalogram signal based on the first preset parameter interval and the basic signal; constructing a loss function based on the intermediate simulated electroencephalogram signal and the reference electroencephalogram signal; iteratively updating the first preset parameter interval based on the loss function until a preset condition is met, and obtaining a first parameter set; obtaining a noise-free simulated electroencephalogram signal based on the basic signal and the first parameter group, wherein the simulated electroencephalogram signal is used as a noise-free electroencephalogram signal in a human body to participate in analysis and research of the electroencephalogram signal; the second acquisition module is used for acquiring a target noise signal based on the initial noise signal and the second parameter group, wherein the target noise signal is used as a noise signal in the collected electroencephalogram signal of the human body to participate in analysis and research of the electroencephalogram signal; the third acquisition module is used for acquiring the first weight of the analog electroencephalogram signal and the second weight of the target noise signal; and the fourth acquisition module is used for acquiring a target simulation acquisition electroencephalogram signal based on the simulation electroencephalogram signal, the target noise signal, the first weight and the second weight, wherein the target simulation acquisition electroencephalogram signal is used as the acquisition electroencephalogram signal to participate in analysis and research of the electroencephalogram signal and reduce acquisition of a real electroencephalogram signal.
One or more embodiments of the present specification provide a generation device for simulating a collected brain electrical signal, which includes a processor, and the processor is configured to execute the method for generating a simulated collected brain electrical signal according to any one of the above embodiments.
One or more embodiments of the present specification provide a computer-readable storage medium, which stores computer instructions, and when the computer instructions in the storage medium are read by a computer, the computer executes the computer to implement the generation method for simulating the acquired brain electrical signals according to any one of the above embodiments.
Drawings
The present description will be further explained by way of exemplary embodiments, which will be described in detail by way of the accompanying drawings. These embodiments are not intended to be limiting, and in these embodiments like numerals are used to indicate like structures, wherein:
FIG. 1 is a schematic diagram of an application scenario of a generation system for simulating acquired brain electrical signals according to some embodiments of the present description;
FIG. 2 is an exemplary block diagram of a generation system for simulating acquired brain electrical signals, shown in accordance with some embodiments herein;
FIG. 3 is a schematic diagram illustrating the generation of an analog acquired brain electrical signal in accordance with some embodiments of the present description;
FIG. 4 is an exemplary flow chart for obtaining a noise-free simulated brain electrical signal according to some embodiments of the present description;
FIG. 5 is an exemplary flow chart illustrating obtaining a target noise signal according to some embodiments of the present description;
FIG. 6 is an exemplary flow diagram illustrating obtaining a first set of parameters according to some embodiments of the present description;
FIG. 7 is an exemplary flow diagram of a method for de-noising acquired electroencephalogram signals, according to some embodiments of the present description;
FIG. 8 is an exemplary flow diagram illustrating obtaining a signal transfer relationship in accordance with some embodiments of the present description;
FIG. 9 is a schematic diagram of a signal transfer model according to some embodiments herein;
FIG. 10 is a schematic diagram of yet another signal transfer model according to some embodiments herein;
fig. 11 is an exemplary flow chart illustrating the determination of a target noise signal according to some embodiments of the present description.
Detailed Description
In order to more clearly illustrate the technical solutions of the embodiments of the present specification, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only examples or embodiments of the present description, and that for a person skilled in the art, without inventive effort, the present description can also be applied to other similar contexts on the basis of these drawings. Unless otherwise apparent from the context, or otherwise indicated, like reference numbers in the figures refer to the same structure or operation.
It should be understood that "system," "device," "unit," and/or "module" as used herein is a method for distinguishing between different components, elements, parts, portions, or assemblies of different levels. However, other words may be substituted by other expressions if they accomplish the same purpose.
As used in this specification and the appended claims, the terms "a," "an," "the," and/or "the" are not to be taken in a singular sense, but rather are to be construed to include a plural sense unless the context clearly dictates otherwise. In general, the terms "comprises" and "comprising" merely indicate that steps and elements are included which are explicitly identified, that the steps and elements do not form an exclusive list, and that a method or apparatus may include other steps or elements.
Flowcharts are used in this specification to illustrate the operations performed by the system according to embodiments of the present specification. It should be understood that the preceding or following operations are not necessarily performed in the exact order in which they are performed. Rather, the steps may be processed in reverse order or simultaneously. Meanwhile, other operations may be added to or removed from these processes.
FIG. 1 is a schematic diagram of an application scenario of a generation system for simulating an acquisition of brain electrical signals according to some embodiments of the present disclosure.
As shown in FIG. 1, an application scenario 100 simulating a generation system for acquiring brain electrical signals may include a server 110, a base signal 120, an initial noise signal 130, a network 140, a storage device 150, and a terminal device 160. Application scenarios of the generation system for simulated acquisition of electroencephalographic signals the simulated acquisition of electroencephalographic signals may be obtained by implementing the methods and/or processes disclosed herein.
Server 110 may communicate with base signal 120, initial noise signal 130, network 140, storage device 150, and terminal device 160 to implement various functions of a generation system for simulating the acquisition of electroencephalograms. In some embodiments, server 110 may receive base signal 120 and initial noise signal 130 via, for example, network 140, and may process them. In some embodiments, server 110 may output relevant data to storage device 150 and terminal device 160 via, for example, network 140. In some embodiments, the server 110 may be a single server or a group of servers. In some embodiments, server 110 may be connected locally to network 140 or remotely from network 140. In some embodiments, the server 110 may be implemented on a cloud platform.
The base signal 120 may be a simple signal. For example, the base signal 120 may be a sine wave. The base signal 120 may be generated by any one or more of a waveform generator, an analog signal generator, a waveform generator, and the like. In some embodiments, the base signal 120 may be transmitted to the server 110, the storage device 150, and the terminal device 160 via the network 140.
The initial noise signal 130 may be a noise signal that has not propagated while the brain electrical signal was acquired. The initial noise signal 130 may be generated by any one or more of a noise generator, an analog signal generator, a noise generator, and the like. In some embodiments, the incipient noise signal 130 may be transmitted to the server 110, the storage device 150, and the terminal device 160 via the network 140.
Network 140 may be used for the transmission of information and/or data. In some embodiments, one or more components (e.g., server 110 and/or storage device 150, etc.) in the application scenario 100 may send information and/or data to another component in the application scenario 100 via the network 140.
Storage device 150 may store data and/or instructions. The data may include data related to the server 110, the terminal device 160, the base signal 120, the initial noise signal 130, and the like. For example, the storage device 150 may store the base signal 120 and the initial noise signal 130. In some embodiments, storage device 150 may store data and/or instructions used by server 110 to perform or use to perform the example methods described in this specification. In some embodiments, a storage device 150 may be connected to the network 140 to communicate with one or more components of the application scenario 100 (e.g., the server 110 and/or the terminal device 160). In some embodiments, the storage device 150 may be part of the server 110. In some embodiments, storage device 150 may include mass storage, removable storage, volatile read-write memory, read-only memory (ROM), etc., or any combination thereof. In some embodiments, the storage device 150 may be implemented on a cloud platform.
Terminal device 160 may refer to one or more terminals or software used by a user. Wherein the user may refer to a researcher. The user can view the relevant data of the respective components in the application scenario 100 through the terminal device 160. In some embodiments, the terminal device 160 may include a mobile device 160-1, a tablet computer 160-2, a laptop computer 160-3, the like, or any combination thereof. In some embodiments, terminal device 160 may be fixed and/or mobile. For example, the terminal device 160 may be directly installed on the server 110, becoming a part of the server 110. As another example, the terminal device 160 may be a mobile device, and a user may carry the terminal device 160 at a remote location with respect to the server 110, the base signal 120, and the initial noise signal 130, and the terminal device 160 may be connected to and/or communicate with the server 110, the storage device 150 via the network 140.
It should be noted that the application scenario 100 is provided for illustrative purposes only and is not intended to limit the scope of this specification. It will be apparent to those skilled in the art that various modifications and variations can be made in light of the description herein. For example, the application scenario 100 may also include a database. However, such changes and modifications do not depart from the scope of the present specification.
FIG. 2 is an exemplary block diagram of a generation system for simulating acquired brain electrical signals, shown in accordance with some embodiments of the present description.
As shown in FIG. 2, the system 200 for generating an analog captured brain electrical signal may include a first acquisition module 210, a second acquisition module 220, a third acquisition module 230, and a fourth acquisition module 240.
The first obtaining module 210 may be configured to obtain a noise-free simulated electroencephalogram signal based on the basic signal and the first parameter group, where the simulated electroencephalogram signal is used as a noise-free electroencephalogram signal in a human body to participate in analysis and research of the electroencephalogram signal. For more on the base signal, the first parameter set, and the simulated brain electrical signal, see FIG. 3 and its associated description. In some embodiments, the first obtaining module 210 may be further configured to obtain an initial first parameter set; obtaining an intermediate simulated electroencephalogram signal based on the initial first parameter group and the basic signal; acquiring a reference electroencephalogram signal; constructing a loss function based on the intermediate simulated electroencephalogram signal and the reference electroencephalogram signal; and iteratively updating the parameters of the initial first parameter group based on the loss function until a preset condition is met, and obtaining the first parameter group. For more on the initial first parameter set, the intermediate simulated brain electrical signal, and the reference brain electrical signal, see FIG. 6 and its associated description. In some embodiments, the first parameter set includes a region-of-interest transfer matrix and a signal source transfer matrix, where elements in the region-of-interest transfer matrix represent transfer relationships when signals are transmitted between different regions of interest, and elements in the signal source transfer matrix represent transfer relationships when signals are transmitted between a signal source and an electrode point in the same region of interest, where different regions of interest represent different brain functional regions in a human brain, and the first obtaining module 210 may be further configured to determine, for each signal source in the virtual brain model, a target basic signal of the signal source based on the region-of-interest transfer matrix and a basic signal emitted by the signal source; aiming at each region of interest in the virtual brain model, determining an initial sub-simulated brain electrical signal corresponding to each region of interest based on a target basic signal and a signal source transfer matrix of each signal source in the region of interest; and simulating the electroencephalogram signal based on the initial sub-simulation corresponding to each region of interest to obtain a simulated electroencephalogram signal. See fig. 4 and its associated description for more on the region of interest transfer matrix, the signal source transfer matrix, the target basis signal, and the initial sub-simulated brain electrical signal.
The second obtaining module 220 may be configured to obtain a target noise signal based on the initial noise signal and the second parameter group, where the target noise signal is used as a noise signal in the acquired electroencephalogram signal of the human body to participate in analysis and research of the electroencephalogram signal. For more on the initial noise signal, the second set of parameters, and the target noise signal, see fig. 3 and its associated description. In some embodiments, the initial noise signal includes a simulated brain noise signal and an electrode noise signal, the second parameter set includes an interest region transfer matrix and an electrode transfer matrix, a transfer relationship between an element characterizing signal in the interest region transfer matrix when propagating between different regions of interest, a transfer relationship between an element characterizing signal in the electrode transfer matrix when propagating between different electrode points, and the second obtaining module 220 is further configured to determine the first sub-noise signal based on the interest region transfer matrix and the simulated brain noise signal; determining a second sub-noise signal based on the electrode point transfer matrix and the electrode point noise signal; and obtaining a target noise signal based on the first sub-noise signal and the second sub-noise signal. For more on the simulated brain noise signal, the electrode point transfer matrix, the first sub-noise signal and the second sub-noise signal, refer to fig. 5 and its related description.
In some embodiments, the second obtaining module 220 may include sub-modules such as a first determining module, a second determining module, and a signal processing module. The first determining module is used for determining the signal transfer relation of the measured object. The signal transfer relationship represents the signal change relationship of the initial noise signal when the initial noise signal is transmitted among all positions of the measured object. For more on the initial noise signal, the measured object and the signal transfer relationship, refer to fig. 7 and its related description. In some embodiments, the first determination module may be further configured to input an initial test signal from each location of the subject, wherein the initial test signal is greater in magnitude than the brain electrical signal of the subject; collecting signals from other positions of the object to be tested to obtain collected test signals; based on the initial test signal and the collected test signal, a signal transfer relationship is determined. For more on the initial test signal and the collected test signal, reference may be made to fig. 8 and its associated description. The second determining module is used for determining a target noise signal based on the initial noise signal and the signal transfer relationship. See fig. 7 and its associated description for more on the target noise signal. In some embodiments, the signal transfer relationship comprises a plurality of simple signal transfer relationships, the simple signal transfer relationships characterizing a signal variation relationship of a first simple noise signal as it propagates between the locations of the measurand, wherein the first simple noise signal is obtained by transforming an initial noise signal, and the second determining module is further configured to transform the initial noise signal into the first simple noise signals of a plurality of different frequencies and intensities; processing the first simple noise signal based on a simple signal transfer relationship corresponding to the first simple noise signal for each first simple noise signal, and determining a second simple noise signal corresponding to the first simple noise signal; and synthesizing each second simple noise signal to obtain a target noise signal. For more on the simple signal transfer relationship, the first simple noise signal, and the second simple noise signal, reference may be made to fig. 10 and its associated description. The signal processing module is used for removing a target noise signal from the acquired electroencephalogram signal acquired from the object to be tested to acquire a noiseless target electroencephalogram signal. For more details regarding the acquisition of the brain electrical signal and the target brain electrical signal, reference may be made to fig. 7 and its associated description.
The third obtaining module 230 may be configured to obtain a first weight of the simulated brain electrical signal and a second weight of the target noise signal. See fig. 3 and its associated description for more on the first weight and the second weight.
The fourth obtaining module 240 may be configured to obtain a target-simulated-acquisition electroencephalogram signal based on the simulated electroencephalogram signal, the target noise signal, the first weight, and the second weight, where the target-simulated-acquisition electroencephalogram signal is used as an acquisition electroencephalogram signal to participate in analysis and research of the electroencephalogram signal and reduce acquisition of a real electroencephalogram signal. For more on the target simulation acquisition of the brain electrical signal, refer to fig. 3 and its associated description.
It should be noted that the above description of the generation system 200 for analog acquisition of electroencephalogram signals and the modules thereof is for convenience of description only and should not limit the present specification to the scope of the illustrated embodiments. It will be appreciated by those skilled in the art that, given the teachings of the present system, any combination of modules or sub-system configurations may be used to connect to other modules without departing from such teachings. In some embodiments, the first acquiring module 210, the second acquiring module 220, the third acquiring module 230 and the fourth acquiring module 240 disclosed in fig. 2 may be different modules in one system, or may be one module to implement the functions of two or more modules described above. For example, each module may share one memory module, and each module may have its own memory module. Such variations are within the scope of the present description.
FIG. 3 is a schematic diagram illustrating generation of an analog acquired brain electrical signal according to some embodiments of the present description. In some embodiments, flow 300 may be performed by server 110. As shown in fig. 3, the process 300 may include the following steps:
and step 310, acquiring a noise-free simulated electroencephalogram signal based on the basic signal and the first parameter group. In some embodiments, step 310 may be performed by the first acquisition module 210.
The base signal may refer to a simple signal of a signal change law. The simulated electroencephalogram signal can be used as a noise-free electroencephalogram signal in a human body to participate in the analysis and research of the electroencephalogram signal. The base signal may include, but is not limited to, a sine signal, a cosine signal, a square wave signal, and the like. The first acquisition module 210 may input the characteristics of the base signal into an analog signal generator to acquire the base signal. The characteristics of the basic signal may include, but are not limited to, the frequency, amplitude, etc. of the basic signal, and the size of the basic signal may be preset, so that the simulated brain electrical signal obtained based on the basic information conforms to the basic characteristics of the real brain electrical signal. For example, the frequency of the basic signal can be set to be less than 100Hz, and the amplitude can be set to range from-200 uV to +200uV.
The first parameter set may refer to a parameter set characterizing the influence of factors such as a region of interest in the virtual brain model, a signal source, and electrode points installed on the virtual brain model on the generation of the base signal when the base signal propagates. In some embodiments, the base signal may be processed by a plurality of different first parameter sets to obtain a plurality of different simulated brain electrical signals. Wherein different regions of interest in the virtual brain model may represent respective functional brain regions in the human brain, respectively. For example, a certain region of interest in the virtual brain model may represent the frontal lobe of the human brain's front that is responsible for related tasks such as concentration, short-term memory tasks, and the like.
It should be understood that when signals are transmitted in the brain of a human body, brain structures of different regions of interest, different signal sources and electrode points for acquiring electroencephalogram signals all affect the signals, so that the signals are changed. In some embodiments of the present description, the influence of the region of interest, the signal source, the electrode point, and the like on the signal may be determined by the first parameter set, so that the obtained simulated electroencephalogram signal is closer to a real electroencephalogram signal without noise.
In some embodiments, the first set of parameters may comprise a varying relationship of the signals as they propagate between different regions of interest of the virtual brain model. The first set of parameters may include a region of interest transfer matrix, which may represent the changing relationship of the underlying signals as they propagate between different regions of interest of the virtual brain model. See fig. 4 and its associated description for more on the region of interest transfer matrix.
In some embodiments, the first parameter set may further include a variation relationship of signals emitted from a signal source in a region of interest in the virtual brain model as they propagate between electrode points in the region of interest. The first parameter set may further include a signal source transfer matrix, which may represent a variation relationship of a basic signal emitted from a signal source in a certain region of interest in the virtual brain model when propagating between electrode points in the region of interest. See fig. 4 and its associated description for further details regarding the signal source transition matrix.
In some embodiments, the elements in the first parameter set may be definite values or interval range values. When the first parameter group is an interval range value, when the basic signal is processed based on the first parameter group, a specific value can be randomly selected from the interval range value to process the basic signal, so as to obtain the simulated electroencephalogram signal. The first parameter sets corresponding to different human bodies or different virtual brain models are different.
In some embodiments, the first set of parameters may be obtained in a variety of ways. For example, the first parameter set may be acquired through a network. For another example, the first parameter set may be obtained by random initialization.
In some embodiments, the first parameter set is obtained based on a first preset parameter interval. The first parameter group may be obtained by setting a first preset parameter interval of the first parameter group and iteratively updating a range of the first preset parameter interval. The first preset parameter interval may refer to a preset interval range of each element in the first parameter set. The first preset parameter interval may be obtained in various ways, for example, may be determined by randomly selecting an initial range. For another example, the extension determination may be made based on a range of an existing first parameter set. The first preset parameter interval corresponding parameter set may be an initial first parameter set. In some embodiments, an intermediate simulated brain electrical signal may be obtained based on the initial first set of parameters and the base signal; constructing a loss function based on the intermediate simulated electroencephalogram signal and the reference electroencephalogram signal; and iteratively updating the initial first parameter group based on the loss function until a preset condition is met, and obtaining the first parameter group. For more on the above embodiment of obtaining the first parameter set, refer to fig. 6 and its related description.
In some embodiments of the present disclosure, by setting a first preset parameter interval of the first parameter group, an approximate range of the first parameter group can be determined, so that the calculation amount for determining the first parameter group is reduced, and the first parameter group is determined more quickly.
The simulated brain electrical signal can refer to the simulated brain electrical signal of human brain. In some embodiments, the basic signal may be processed based on the first parameter set, and the influence of the region of interest in the virtual brain model, the signal source, the electrode points installed on the virtual brain model, and the like on the basic signal when the basic signal is acquired is determined, so as to obtain the simulated electroencephalogram signal. And acquiring a noise-free analog electroencephalogram signal. In some embodiments, for each region of interest in the virtual brain model, determining an initial sub-simulated brain electrical signal corresponding to the region of interest based on the signal source transfer matrix and the base signal; and simulating the electroencephalogram signal based on the region-of-interest transfer matrix and the initial sub-simulation electroencephalogram signals corresponding to the regions of interest to obtain the simulated electroencephalogram signal. See figure 4 and its associated description for more on the above embodiments.
In some embodiments, the acquired simulated electroencephalogram signal can have the basic characteristics of the electroencephalogram signal by emitting basic signals from a plurality of signal sources of the virtual brain model and overlapping the basic signals. The basic features of the electroencephalogram signal may include, but are not limited to, amplitude features (such as an amplitude range), frequency features (such as a frequency range) of the electroencephalogram signal, and the like. For example, the fundamental features of the brain electrical signal may include an amplitude ranging from-200 uV to +200uV, and a frequency less than 100Hz. 3 signal sources in the virtual brain model can send out 3 sinusoidal signals with amplitudes of 10uV, 30uV and 100uV and frequencies of 5Hz, 20Hz and 40Hz respectively, the 3 sinusoidal signals are superposed to obtain a more complex simulated electroencephalogram signal, the amplitude of the simulated electroencephalogram signal is less than 100uV, the frequency of the simulated electroencephalogram signal has 3 components and is less than 100Hz, and therefore the simulated electroencephalogram signal can have the basic characteristics of the electroencephalogram signal.
It should be understood that the simulated electroencephalogram signal is directly obtained by processing the basic signal through the first parameter group, and therefore, the simulated electroencephalogram signal does not contain a noise signal caused by the activity of the acquisition equipment or other parts of the human body when the electroencephalogram signal of the human body is acquired.
In step 320, a target noise signal is obtained based on the initial noise signal and the second parameter set. In some embodiments, step 320 may be performed by the second acquisition module 220.
The initial noise signal may refer to a noise signal that has not been propagated while the electroencephalogram signal is being acquired. The target noise signal can be used as a noise signal in the collected electroencephalogram signal of a human body to participate in the analysis and research of the electroencephalogram signal.
When the electroencephalogram signals are collected, various factors influence the collection, so that the collected electroencephalogram signals contain various noise signals. Accordingly, the initial noise signal may include a variety of noise signals. In some embodiments, the initial noise signal may be determined by acquisition or simulation. See fig. 5 and its associated description for more details regarding the determination of the initial noise signal.
The second parameter set may refer to a parameter set characterizing an influence of factors such as a region of interest in the virtual brain model, a signal source, and an electrode point installed on the virtual brain model on the generation of the initial noise signal when the initial noise signal propagates.
Similar to the first parameter set, the second parameter set may also include a region of interest transfer matrix. In some embodiments, the second parameter set may further include an electrode point transfer matrix, which may represent a relationship of changes in signals as they propagate between electrode points in the virtual brain model. See figure 4 and its associated description for more on the electrode point transfer matrix.
In some embodiments, the second parameter set may be obtained in a variety of ways. For example, the region of interest transfer matrix may be acquired through a network.
In some embodiments, the second parameter set is obtained based on a second preset parameter interval. The second parameter set may be obtained by setting a second preset parameter interval of the second parameter set, and iteratively updating an interval range of the second preset parameter interval. The second preset parameter interval may refer to a preset interval range of an element in the second parameter value, and the second preset parameter interval may be obtained in a variety of ways, for example, may be determined by randomly selecting an initial range. The second preset parameter interval corresponding parameter set may be an initial second parameter set. In some embodiments, the second parameter set may be determined based on the initial second parameter set. See fig. 6 and its associated description for further details regarding determining the second parameter set based on the initial second parameter set.
In some embodiments, an initial test signal can also be input from each electrode point of the measured object, wherein the magnitude of the initial test signal is larger than that of the brain electrical signal of the measured object; collecting signals from other electrode points of the object to be tested to obtain collected test signals; determining a signal transfer relationship between the electrode point and other electrode points based on the initial test signal and the collected test signal; and determining an electrode point transfer matrix based on the signal transfer relationship between each electrode point and other electrode points. For more on the above described embodiment of determining the electrode point transfer matrix, reference is made to fig. 8 and its associated description.
The target noise signal may refer to a noise signal in the analog acquired electroencephalogram signal. In some embodiments, the initial noise signal may be processed based on the second parameter set, and the influence of the region of interest in the virtual brain model, the signal source, the electrode points installed on the virtual brain model, and the like on the initial noise signal when the initial noise signal is acquired may be determined to obtain the target noise signal. In some embodiments, a first sub-noise signal is determined based on the region of interest transfer matrix and the simulated brain noise signal; determining a second sub-noise signal based on the electrode point transfer matrix and the electrode point noise signal; and obtaining a target noise signal based on the first sub-noise signal and the second sub-noise signal. See figure 5 and its associated description for more on the above embodiments.
Step 330, obtain a first weight of the analog electroencephalogram signal and a second weight of the target noise signal. In some embodiments, step 330 may be performed by the third acquisition module 230.
The first weight may refer to a specific gravity of the simulated brain electrical signal in the target simulated acquired brain electrical signal. The second weight may refer to a specific gravity of the target noise signal in the target simulated acquired brain electrical signal. The first weight and the second weight can be predetermined by analyzing the ratio of the electroencephalogram signal to the noise signal in the actually acquired electroencephalogram signal.
And 340, acquiring a target analog acquisition electroencephalogram signal based on the analog electroencephalogram signal, the target noise signal, the first weight and the second weight.
The target analog acquisition of the electroencephalogram signal may refer to an analog acquisition of the electroencephalogram signal. The target simulation collection of the electroencephalogram signals can be used for collecting the electroencephalogram signals to participate in analysis and research of the electroencephalogram signals and reduce the collection of real electroencephalogram signals. The collected electroencephalogram signals comprise electroencephalogram signals and noise signals, and correspondingly, the target simulation collected electroencephalogram signals can also comprise simulation electroencephalogram signals and target noise signals.
In some embodiments, the target simulated acquired brain electrical signal may be determined by equation (1):
x(t)=αx s (t)+βx n (t) (1) wherein x (t) represents the target analog acquisition brain electrical signal, x s (t) represents an analog brain electrical signal, x n (t) represents a target noise signal, and α and β represent a first weight and a second weight, respectively.
Some embodiments of the present description may determine, by setting the first parameter group and the second parameter group, an influence of a region of interest in the virtual brain model, a signal source, an electrode point installed on the virtual brain model, and other factors on the signal, and further may obtain a more real target-simulated acquired electroencephalogram signal. Some embodiments of the present description may use the acquired analog electroencephalogram signal, the target noise signal, and the target acquired electroencephalogram signal for analyzing and researching the electroencephalogram signal, thereby avoiding the problem of lack of research data during analyzing and researching the electroencephalogram signal. Meanwhile, the target acquisition of the electroencephalogram signals can be used for reducing the acquisition of the real electroencephalogram signals, and the acquisition cost of the real electroencephalogram signals in the analysis and research of the electroencephalogram signals is reduced.
FIG. 4 is an exemplary flow chart for obtaining a noise-free simulated brain electrical signal according to some embodiments of the present description. In some embodiments, the flow 400 may be performed by the first obtaining module 210. As shown in fig. 4, the process 400 may include the following steps:
and step 410, determining a target basic signal of each signal source in the virtual brain model based on the region of interest transfer matrix and the basic signal emitted by the signal source.
The target base signal may be a signal obtained by influencing a base signal emitted by a certain signal source by other regions of interest.
In some embodiments, the first set of parameters may include a region of interest transfer matrix. The elements in the region of interest transfer matrix may characterize the transfer relationship of the signal as it propagates between different regions of interest. The region of interest transfer matrix may be a matrix of n x n, where n represents the number of regions of interest. In some embodiments, the elements in the region of interest transfer matrix may be real numbers, which are adjustment parameters between corresponding regions of interest, and may be used to determine a transfer relationship when a signal propagates between corresponding regions of interest. For example, a certain element in the region of interest transfer matrix may be a real number α, and the target basis signal may be obtained based on the following formula:
Figure BDA0003773930820000061
wherein the content of the first and second substances,
Figure BDA0003773930820000062
a target base signal representing the ith signal source in the jth region of interest,
Figure BDA0003773930820000063
represents the basic signal emitted by the signal source, alpha is the adjustment parameter of the signal propagating from the l interested area to the j interested area,
Figure BDA0003773930820000064
representing the base signal from the ith signal source in the ith region of interest.
In some embodiments, the elements in the region of interest transfer matrix may also be transfer functions that characterize the effect of the corresponding region of interest on the signal. The transfer function may be a linear function or a nonlinear function. Reference may be made to fig. 6 and its associated description regarding the manner of obtaining the region of interest transfer matrix.
In some embodiments, the target base signal may be obtained based on the following formula:
Figure BDA0003773930820000065
Figure BDA0003773930820000066
wherein the content of the first and second substances,
Figure BDA0003773930820000067
a target base signal representing the ith signal source in the jth region of interest,
Figure BDA0003773930820000068
representing the underlying signal emitted by the signal source,
Figure BDA0003773930820000069
representing the influence of other interested regions on the signal source, T representing interested region transfer matrix, T l Representing the l-th row in the region of interest transfer matrix,
Figure BDA00037739308200000610
can be the average value of the signals emitted by the m signal sources of the ith region of interest,
Figure BDA00037739308200000611
representing the base signal emitted by the ith signal source in the ith region of interest.
Step 420, for each region of interest in the virtual brain model, determining an initial sub-simulated brain electrical signal corresponding to the region of interest based on the target basic signal of each signal source in the region of interest and the signal source transfer matrix.
The initial sub-simulated brain electrical signal can be a signal emitted from a certain region of interest in the virtual brain model. The initial sub-analog electroencephalogram signal can be a signal formed by superposing target basic signals of a plurality of signal sources in the region of interest under the influence of the electrode points.
In some embodiments, the first set of parameters may further include a signal source transition matrix. The elements in the signal source transfer matrix can represent the transfer relation between the signal source and the electrode points in the same region of interest during transmission. The signal source transfer matrix may be a matrix of m x k, where m represents the number of signal sources in the region of interest and k represents the number of electrode points in the virtual brain model. Similar to the region-of-interest transfer matrix, the elements in the signal source transfer matrix may be real numbers, which are adjustment parameters between the corresponding signal source and the electrode points, and may be used to determine a transfer relationship when a signal propagates between the corresponding signal source and the electrode points. The elements in the signal source transfer matrix may also be transfer functions that may characterize the effect of the corresponding electrode point on the target basis signal of the corresponding signal source. For the acquisition manner of the signal source transition matrix, reference may be made to fig. 6 and its related description.
In some embodiments, the initial sub-simulated brain electrical signals may be obtained based on the following formula:
Figure BDA0003773930820000071
wherein the content of the first and second substances,
Figure BDA0003773930820000072
an initial sub-simulated brain electrical signal representing the jth region of interest,
Figure BDA0003773930820000073
representing the target base signal of the ith signal source in the jth region of interest, a representing the signal source transfer matrix,
Figure BDA0003773930820000074
representing the ith row in the signal source transfer matrix and m representing the number of signal sources in the region of interest.
And 430, simulating the electroencephalogram signal based on the initial sub-simulation corresponding to each region of interest to obtain a simulated electroencephalogram signal.
In some embodiments, the simulated electroencephalogram signals can be obtained by performing superposition processing based on the initial sub-simulated electroencephalogram signals corresponding to the respective regions of interest. The simulated brain electrical signal may be obtained based on the following formula:
Figure BDA0003773930820000075
wherein X s (t) represents the simulated brain electrical signal,
Figure BDA0003773930820000076
the initial sub-simulated brain electrical signals representing the jth region of interest, n representing the number of regions of interest.
Fig. 5 is an exemplary flow chart illustrating obtaining a target noise signal according to some embodiments of the present description. In some embodiments, the flow 500 may be performed by the second obtaining module 220. As shown in fig. 5, the process 500 may include the following steps:
step 510, determining a first sub-noise signal based on the region of interest transfer matrix and the simulated brain noise signal.
The initial noise signal may include a simulated brain noise signal and an electrode point noise signal. The analog brain noise signal can refer to a noise signal in a human brain in the analog collected human brain electrical signals, and the electrode point noise signal can refer to a noise signal brought by an electrode point in the collected human brain electrical signals. The simulated brain noise signal may include a background noise signal and a pink noise signal. The background noise signal and the pink noise signal may be obtained from historical data or from a network.
In some embodiments, the second set of parameters may also include a region of interest transfer matrix.
The first sub-noise signal may be a noise signal determined based on the background noise signal and the pink noise signal. The first sub-noise signal may be determined based on the following equation:
Figure BDA0003773930820000077
Figure BDA0003773930820000078
Figure BDA0003773930820000079
wherein the content of the first and second substances,
Figure BDA00037739308200000710
representing the noise signal due to the background noise signal in the first sub-noise signal, a representing the signal source transfer matrix,
Figure BDA00037739308200000711
represents the ith row in the signal source transfer matrix, m represents the number of signal sources in the region of interest, n represents the number of regions of interest in the virtual brain model,
Figure BDA00037739308200000712
representing the background noise signal emitted by the ith signal source in the jth region of interest; x is the number of 1/f (t) represents a noise signal due to a pink noise signal in the first sub-noise signal, f represents a frequency of the pink noise signal,
Figure BDA00037739308200000713
representing a pink noise signal emitted by an ith signal source in a jth region of interest; x is a radical of a fluorine atom 1 (t) represents a first sub-noise signal, θ 0 、θ 1 The weighting parameters respectively representing the noise signals caused by the background noise signal and the pink noise signal in the first sub-noise signal can be determined according to the preset setting.
And step 520, determining a second sub-noise signal based on the electrode point transfer matrix and the electrode point noise signal.
In some embodiments, the second set of parameters may include an electrode point transfer matrix. The elements in the electrode point transfer matrix can represent the transfer relation of signals when the signals are transmitted between different electrode points. The electrode point transfer matrix may be a matrix of k x k, where k is the number of electrode points in the virtual brain model. Similar to the region of interest transfer matrix, the elements in the electrode point transfer matrix may be real numbers, which are adjustment parameters between corresponding electrode points, and may be used to determine a transfer relationship when a signal propagates between corresponding electrode points. The elements in the electrode point transfer matrix may also be transfer functions that characterize the effect of the corresponding electrode point on the electrode point noise signal.
Each element of the matrix may be a transfer function that characterizes the effect of the corresponding motor point on the electrode point noise signal generated by the electrode point. It should be understood that the element located at the diagonal position of the electrode point transfer matrix may be 1, indicating that the electrode point has no effect on itself. For more on the acquisition of the electrode point transfer matrix, reference may be made to fig. 8 and its associated description.
The second sub-noise signal may be a noise signal determined based on the electrode point noise signal. In some embodiments, the second sub-noise signal may be determined according to the following equation:
Figure BDA0003773930820000081
x 2 (t)=θ 2 ε (t) (11) represents the noise signal due to the electrode point noise signal in the second sub-noise signal, σ p (t) represents the noise signal of the electrode point of the p-th electrode point, H represents the electrode point transfer matrix, H p Represents the p-th row in the electrode point transfer matrix, and k represents the number of electrode points; x is a radical of a fluorine atom 2 (t) represents a second sub-noise signal, θ 2 The weighting parameter indicating the noise signal due to the electrode point noise signal in the second sub-noise signal can be determined by setting in advance.
In step 530, a target noise signal is obtained based on the first sub-noise signal and the second sub-noise signal.
In some embodiments, the target noise signal may be determined according to the following equation:
x n (t)=x 1 (t)+x 2 (t) (12) wherein x n (t) represents a target noise signal, x 1 (t) denotes a first sub-noise signal, x 2 (t) represents the second sub-noise signal.
Some embodiments of the present disclosure can determine the influence of the signal source, the region of interest, the electrode point, and other factors on the signal by setting the region of interest transfer matrix, the signal source transfer matrix, and the electrode point transfer matrix, the acquired simulated electroencephalogram signal and the target noise signal are more real and more accord with the acquired electroencephalogram signal which is actually acquired.
It is worth to be noted that, in the modern technology, the collected electroencephalogram signals can be subjected to denoising processing based on a machine learning model, namely a denoising model, so that noiseless electroencephalogram signals are obtained. At this time, when a large amount of training data is needed to train the denoising model, the training data includes the acquired electroencephalogram signal and the acquired electroencephalogram signal after denoising. However, the existing data for acquiring the electroencephalogram signals are few, the acquisition cost is high, and because the electroencephalogram signals originally existing in the human body are unknown, the noise signals in the acquired electroencephalogram signals are also unknown, so that the acquired electroencephalogram signals cannot be subjected to denoising processing, and therefore, the training data are difficult to acquire in practice. Some embodiments of this description can generate a large amount of target simulation collection brain electrical signals and noiseless simulation brain electrical signals in order to simulate collection brain electrical signals and collection brain electrical signals after removing noise respectively to can train the model of removing noise as training data, make the model of removing noise after the training have better generalization effect, the output of the model of removing noise is more accurate.
FIG. 6 is an exemplary flow diagram illustrating obtaining a first parameter set according to some embodiments of the present description. In some embodiments, the flow 600 may be performed by the server 110 or the first obtaining module 210. As shown in fig. 6, the process 600 may include the following steps:
at step 610, an initial first parameter set is obtained.
The initial first parameter set may refer to a parameter set corresponding to the first preset parameter interval. When the first preset parameter interval is determined, the corresponding initial first parameter set may be determined. In some embodiments, the first parameter set may include a region of interest transfer matrix and a signal source transfer matrix, and correspondingly, the initial first parameter set may include an initial region of interest transfer matrix and an initial signal source transfer matrix.
Step 620, obtaining an intermediate simulated electroencephalogram signal based on the initial first parameter set and the basic signal.
The intermediate electroencephalogram signal can be a simulated human electroencephalogram signal obtained by processing the basic signal through the initial first parameter set. In some embodiments, the base signal may be processed based on the initial first parameter set to obtain an intermediate brain electrical signal. The method for processing the basic signal based on the initial first parameter group may refer to a part of the description where the basic signal is processed based on the first parameter group to obtain the simulated electroencephalogram signal. For example, the method for processing the basic signal based on the initial first parameter set may refer to formulas (2) to (5) in fig. 4, replace the region-of-interest transfer matrix in the formulas with the initial region-of-interest transfer matrix, replace the signal source transfer matrix with the initial signal source transfer matrix, and obtain the final signal which may be the intermediate simulated electroencephalogram signal.
Step 630, acquiring a reference electroencephalogram signal.
The reference brain electrical signal may refer to a noiseless brain electrical signal in a human body. The reference brain electrical signal can be acquired through a human body brain electrical signal collected historically or through a network.
And step 640, constructing a loss function based on the intermediate simulated brain electrical signal and the reference brain electrical signal.
And step 650, iteratively updating the parameters of the initial first parameter set based on the loss function until a preset condition is met, and obtaining the first parameter set.
In some embodiments, the parameters of the initial first set of parameters may be iteratively updated based on a loss function. And when the initial first parameter group and the loss function of the reference electroencephalogram signal meet the preset condition, obtaining the first parameter group. The preset condition may be that the difference between the intermediate analog signal and the reference electroencephalogram signal is smaller than a threshold. The preset condition may also be other conditions, such as a loss function convergence, a threshold number of iterations, etc. The method of updating the parameters of the initial first set of parameters may be a gradient descent method. In some embodiments, a regularization term may also be added to the loss function to improve iteration efficiency and speed up the convergence of the loss function.
In some embodiments, an intermediate simulated electroencephalogram signal can be obtained based on an initial region-of-interest transfer matrix, an initial signal source transfer matrix and a basic signal, a loss function is constructed based on the intermediate simulated electroencephalogram signal and a reference electroencephalogram signal, parameters of the initial region-of-interest transfer matrix and the initial signal source transfer matrix are updated iteratively based on the loss function, and when the loss function meets a preset condition, specific parameters in the region-of-interest transfer matrix and the signal source transfer matrix can be determined.
In some embodiments, the loss function may include a first loss term and a second loss term. The first loss item can reflect the relation between the initial region of interest transfer matrix and the basic signal emitted by the signal source, and the second loss item can reflect the relation between the initial signal source transfer matrix and the target basic signal of each signal source in the region of interest. The first loss term and the second loss term may be combined in various ways. For example, a weighted sum may set different weights for the first loss term and the second loss term to reflect different influences of different factors on the brain electrical signal.
Some embodiments of the present description may preset a larger parameter interval range, that is, a first preset parameter interval, for the initial parameter set, so as to avoid more calculation amounts, and perform iterative update based on the parameter interval, so as to obtain an iterative calculation result more quickly, thereby obtaining the first parameter set.
The second parameter set may be acquired based on a second preset parameter interval, similar to the acquisition of the first parameter set based on the first preset parameter interval. That is, an initial second parameter group corresponding to a second preset parameter interval may be acquired, and an intermediate noise signal may be acquired based on the initial second parameter group and the initial noise signal; acquiring a reference noise signal; constructing a loss function based on the intermediate noise signal participating in the reference noise signal; and iteratively updating the initial second parameter group based on the loss function until a preset condition is met, and obtaining a second parameter group. The intermediate noise signal may refer to a noise signal in the acquired simulated acquired electroencephalogram signal obtained by processing the initial noise signal through the initial second parameter set, and the reference noise signal may refer to a noise signal in the actual acquired electroencephalogram signal. Further details regarding the above-described embodiments may be found in relation to fig. 6.
The signal transfer relationship can be used to represent the transfer relationship of a signal as it propagates between different electrode points. In some embodiments, the signal transfer relationship may include an electrode point transfer matrix, also referred to as a signal transfer matrix. The signal transfer relationships may also include signal transfer models. In some embodiments, the acquired electroencephalogram signals may be denoised based on a signal transfer relationship.
FIG. 7 is an exemplary flow chart of a method for de-noising acquired electroencephalogram signals according to some embodiments presented herein. In some embodiments, flow 700 may be performed by server 110. As shown in fig. 7, the process 700 may include the following steps:
and step 710, determining a signal transfer relationship of the measured object, wherein the signal transfer relationship represents a signal change relationship of the initial noise signal when the initial noise signal propagates among the positions of the measured object. In some embodiments, step 710 may be performed by the first determining module.
The measured object may refer to an object for which a signal transfer relationship needs to be determined. The object to be measured may be a living body, for example, a head region of a human body. The subject may also be a non-biological object, such as a virtual head model.
The initial noise signal may refer to a signal before the noise signal in the acquired electroencephalogram signal is propagated. The collected electroencephalogram signals can refer to electroencephalogram signals of a measured object collected through the electrode points.
It should be understood that, when the electroencephalogram signal of the object to be tested is collected, there are various factors (for example, the operation of the electroencephalogram collecting device or the physiological activities of the object to be tested) that affect the collection process, so that the collected electroencephalogram signal contains various noise signals. Noise signals commonly found in the acquired electroencephalogram signals can include non-biological artifact signals and biological artifact signals. The non-biological artifact signal may be a noise signal brought by an external environment, a device, or the like, and may include, but is not limited to, a noise signal brought by an electroencephalogram acquisition device, a noise signal brought by mains interference, or the like. The non-biological artifact signal can be obtained by querying relevant data. For example, the noise signal brought by the electroencephalogram acquisition device of the model can be determined through a network. The biological artifact signal may be a noise signal caused by the physiological activity of the object to be measured, and may include but is not limited to an electrocardiographic signal caused by the heartbeat, an electromyographic signal caused by the muscle activity, an electrooculogram signal caused by the eyeball rotation, and the like. The biological artifact signal can be acquired by the related acquisition equipment. Due to the difference of biological individuals, the biological artifact signals corresponding to different detected objects are different.
The signal transfer relationship may be used to determine the variation of the initial noise signal as it propagates between the various locations of the object under test. In some embodiments, the change of the measured object when the signal at one position propagates to another position can be determined based on the signal transfer relation. For example, based on the signal transfer relationship, the position O from the object to be measured can be determined i A certain signal S is transmitted i Position O of propagation to the object to be measured j After that, change to the signal S j . In some embodiments, the signal transfer relationship is different for different subjects due to different physiological conditions and different brain structures. For example, the signal transfer relationships between elderly people and children are different. For another example, a 26 year old female may have a different signal transfer relationship with a 26 year old male.
In some embodiments, the signal transfer relationship may be characterized as a signal transfer matrix of N × N, where N is the number of electrodes of the measurand, each electrode may represent a different location of the measurand. Each element in the signal transfer matrix may be a transfer function between corresponding two locations of the measurand. It should be understood that the transfer function between a location in the signal transfer matrix and the location itself may be 1 to indicate that the signal itself does not change when it is not propagating. In some embodiments, reference may be made to fig. 4 and its associated description for more information on obtaining a signal transfer matrix.
In some embodiments, the signal transfer relationship may also be characterized as a signal transfer model. The initial noise signal may be processed based on a signal transfer model to obtain a target noise signal. For more on the signal transition model, see fig. 5 and its associated description.
In some embodiments, when the measured object is a virtual head model, the attenuation relationship of each position in the virtual head model can be determined based on the material and shape of the virtual head model, so as to determine the signal transfer relationship of the virtual head model.
In some embodiments, an initial test signal may also be input from a first location of the subject, wherein the magnitude of the initial test signal is greater than the magnitude of the brain electrical signal of the subject; collecting a signal from a second position of the object to be tested to obtain a collected test signal; based on the initial test signal and the collected test signal, a signal transfer relationship is determined. For more on the above embodiments, reference is made to fig. 4 and its associated description.
In step 720, a target noise signal is determined based on the initial noise signal and the signal transfer relationship. In some embodiments, step 720 may be performed by the second determination module.
The target noise signal may refer to a noise signal in the acquired electroencephalogram signal. In some embodiments, the target noise signal may be a noise set of noise signals acquired at various locations of the object under test.
In some embodiments, after the initial noise signals are determined, the corresponding underlying features of each initial noise signal may be determined. The corresponding basic characteristics of the initial noise signal may include, but are not limited to, the amplitude, variance, etc. of the signal. For each electrode point of the plurality of electrode points, when electroencephalogram signals are collected, signals collected by the electrode points can be dynamically evaluated, and whether initial noise signals exist in the signals collected by the electrode points or not is judged by comparing the basic characteristics of the collected signals with the basic characteristics corresponding to the initial noise signals. When the initial noise signal exists in the signals acquired by the electrode points, the initial noise signal can be determined as a target noise signal in the electroencephalogram signals acquired by the electrode points correspondingly. Meanwhile, the propagated initial noise signals collected by other electrode points can be determined through a signal transfer relation, and the propagated initial noise signals are determined as target noise signals in the collected electroencephalogram signals collected by other electrode points.
Step 730, removing the target noise signal from the acquired electroencephalogram signal acquired from the object to be tested, and acquiring a noiseless target electroencephalogram signal. In some embodiments, step 730 may be performed by a signal processing module.
The target EEG signal can be the noiseless EEG signal of the object to be tested. The target brain electrical signal can be used for analyzing and diagnosing the brain diseases of the tested object.
In some embodiments, when the target noise signal collected by an electrode point is an initial noise signal that is not propagated at the electrode point, the initial noise signal may be directly removed from the collected electroencephalogram signal collected by the electrode point, so as to obtain the target electroencephalogram signal of the electrode point.
In some embodiments, when the target noise signal collected at a certain electrode point is the propagated initial noise signal, the target electroencephalogram signal of the electrode point can be determined based on the following formula:
Figure BDA0003773930820000101
wherein S is clean Target EEG signal for electrode point with position j, S obs For the acquisition of the EEG signal of the electrode point, h is a signal transfer matrix, h ij Representing the transfer function of a signal propagating from position i to position j in a signal transfer matrix, S i Is the initial noise signal originating from the electrode point with position i, and k is the number of initial noise signals.
In some embodiments, the initial noise signal at a certain position may be processed based on a signal transfer model to obtain a target noise signal in the acquired electroencephalogram signals at other positions. And removing target noise signals in the acquired electroencephalogram signals at other positions to obtain target electroencephalogram signals at corresponding positions.
In some embodiments of the present description, a signal transfer relationship when a signal is transmitted between different positions is determined, so that a target noise signal after transmission can be accurately and quickly determined based on an initial noise signal and the signal transfer relationship, and thus the target noise signal in an acquired electroencephalogram signal can be removed to obtain a noise-free target electroencephalogram signal. Compared with the existing method for denoising the acquired electroencephalogram signals, the method has the advantage that the cost is greatly reduced. Meanwhile, the corresponding signal transfer relationship is determined based on each measured object, so that the determined signal transfer relationship is more accurate and accords with the actual condition of the measured object, and the target electroencephalogram signal cannot be removed on the basis of accurately and completely removing the target noise signal in the acquired electroencephalogram signal.
Fig. 8 is an exemplary flow diagram illustrating obtaining a signal transfer relationship in accordance with some embodiments of the present description. In some embodiments, the flow 800 may be performed by a first determination module. As shown in fig. 8, the process 800 may include the following steps:
step 810, aiming at each position of the tested object, inputting an initial test signal from the position, wherein the magnitude of the initial test signal is larger than that of the electroencephalogram signal of the tested object.
The initial test signal may refer to a test signal input to the object to be tested, and the initial test signal may be used for a change relationship when the test signal propagates between different electrode points. In some embodiments, the initial test signal is an order of magnitude greater than the brain electrical signal of the human body. For example, the magnitude of the electroencephalogram signal of the human body is μ V, the magnitude of the initial test signal may be 3 magnitudes larger than the electroencephalogram signal of the human body, that is, the magnitude of the selected initial test signal may be mV. In some embodiments, the initial test signal may comprise a plurality of different frequency, different strength signals. In some embodiments, the initial test signal may be determined by a preset. For example, the initial test signal may be a preset pulse signal having an order of magnitude larger than that of the brain electrical signal of the object to be tested. Each position of the object to be measured may refer to each electrode point of the object to be measured, and the initial test signal may be input at one electrode point of the object to be measured.
It should be understood that, because the magnitude of the initial test signal is greater than that of the electroencephalogram signal of the tested object, when the signal is collected, the collected signal is less affected by the electroencephalogram signal, and the accuracy of the test result can be ensured. Meanwhile, the initial test signal should be not higher than the order of magnitude of the signal that the human body can bear to ensure the safety of the tested object, for example, the amplitude range of the initial test signal may be 20mV to 200mV.
And step 820, collecting signals from other positions of the tested object to obtain a collected test signal.
Collecting the test signal may refer to collecting a propagated signal of the initial test signal input at the position at another position. Other locations may be other electrode points. Correspondingly, acquiring the test signal may include acquiring signals at other electrode points based on the electrode point at the location. For example, electrode points a to D may be provided on the object to be measured, where the position where the initial test signal is input is the electrode point a, and the other positions may be motor points B, C, and D. Correspondingly, signals can be acquired from the motor points B, C, D to obtain the acquisition test signals.
It will be appreciated that the initial test signal is affected by other electrode points as it propagates between them, so the collected test signal may be different from the initial test signal.
Step 830, determining a signal transfer relationship based on the initial test signal and the collected test signal.
In some embodiments, the initial test signal and the collected test signal may be modeled or analyzed using various data analysis algorithms, such as regression analysis, discriminant analysis, and the like, to determine the signal transfer relationship.
In some embodiments, when the elements in the signal transfer matrix may be real, the individual elements in the matrix may be determined by based on the following formula:
S j (t)=βs i (t) (14)
wherein S is j (t) represents the collected test signal collected by the electrode point j, beta is the adjustment parameter of the signal transmitted from the electrode point i to the electrode point j,s i (t) represents an initial test signal input from the electrode point i.
In some embodiments, the signal transfer relationships may include a plurality of simple signal transfer relationships. The simple signal transfer relationship may refer to a change relationship of a simple signal with a relatively regular signal change when the signal is transmitted between a plurality of positions of the object to be measured. In some embodiments, the input initial test signal may be transformed into a plurality of initial simple test signals of different frequencies and intensities, and the collected test signals collected at the other respective electrode points may be transformed into a plurality of collected simple test signals of different frequencies and intensities; for each initial simple test signal, determining a simple signal transfer relationship corresponding to the initial simple test signal based on the initial simple test signal and the corresponding acquired simple test signal; and synthesizing the simple signal transfer relations to obtain a signal transfer relation containing a plurality of simple signal transfer relations. The initial simple test signal may be a simple signal obtained by transforming the initial test signal, and the collected simple test signal may be a simple signal obtained by transforming the collected test signal, wherein a transformation method of the signal may be fourier transformation. For example, the initial simple test signal and the acquisition simple test signal may both be sine wave signals.
In some embodiments, the initial test signal input at location i may be fourier transformed to obtain an initial set S of simple test signals of M different phases and frequencies, where S is a matrix of N x M and N is the number of electrode points. Under the condition that no signal is input at other positions of the object to be tested and the initial test signal is not propagated, each element in the ith row in the S respectively has each initial simple test signal, and other positions in the S can be 0, so that the representation that no signal is contained in other positions is realized. After the initial test signal is propagated, fourier transform is performed on the collected test signals collected at other positions, so that a collection S ' including a plurality of collected simple test signals can be obtained, where S ' is also a matrix of N × M, each element in S ' represents a collected simple test signal collected at a corresponding electrode point, and the collected simple test signal is a signal obtained by propagating the corresponding initial simple test signal. A calculation can then be made based on S and S' to determine the signal transfer matrix H such that the following equation holds:
S′=HS (15)
the elements of H are all conduction functions, and represent the relationship of change when the signal propagates at the corresponding position. E.g. h ij May be an element in H that represents the transfer function of a signal propagating from location i to location j. In some embodiments, the conductance function may take a variety of forms. The transfer function h is shown by the following formula ij It can be equivalent to a FIR (Finite Impulse Response) filter:
y[n]=b 0 x[n]+b 1 x[n-1]+…+b L x[n-l] (16)
Figure BDA0003773930820000111
wherein, y [ n ]]To collect simple test signals, x [ n ]]The initial simple test signal is used, n is the signal length, L is the parameter number, the initial simple test signal can be determined through presetting, and when L is less than or equal to M, the conduction function h can be determined through solving a multivariate linear equation set ij All of the parameters in (1).
In some embodiments, the signal transfer model may also be trained based on the initial test signal and the collected test signal, resulting in a trained signal transfer model. For more on the signal transfer model, see fig. 9 and its associated description.
It should be understood that the brain structure of the subject is nearly fixed, so the relationship of the signal changes that propagate between the locations of the subject should be the same even if the two signals differ in intensity. Therefore, some embodiments of the present disclosure may determine a signal transfer relationship of the object under test by analyzing the initial test signal and the collected test signal, and the signal transfer relationship may also represent a signal variation relationship of the initial noise signal when propagating between various positions of the object under test.
Some embodiments of the present description can quickly determine the signal transfer relationship of each measured object by an initial test signal and a collected test signal, and ensure the accuracy of the signal transfer relationship, thereby avoiding errors caused by differences of individual measured objects during denoising.
Fig. 9 is a schematic diagram of a signal transfer model according to some embodiments described herein.
In some embodiments, the initial noise signal may be processed based on a signal transfer model to obtain a target noise signal. As shown in fig. 9, the inputs to the signal transfer model 930 may include an initial noise signal 910 and a location of the initial noise signal 920, and the output may include a target noise signal 940. In some embodiments, the signal transfer model may include, but is not limited to, a deep neural network model, a support vector machine model, and the like.
In some embodiments, the signal transfer model may be obtained by training a machine learning model with training samples. As shown in fig. 9, the signal transition model may be obtained by training the initial signal transition model 950 by using the training sample 960 and the label 970, wherein the initial signal transition model may be a signal transition model with no parameter set. The training sample 960 may include an initial test signal and the location of the initial test signal and the tag 970 may include a collection test signal. The training samples and labels can be obtained in the manner shown in fig. 8 and the related description. Inputting a plurality of groups of training samples 960 with labels 970 into the initial signal transfer model 950, constructing a loss function based on the output of the initial signal transfer model 950 and the labels 970, iteratively updating parameters of the initial signal transfer model 950 based on the loss function until preset conditions are met, finishing training, and acquiring a trained signal transfer model 930. The preset conditions may include, but are not limited to, the loss function being less than a threshold, convergence, or a training period reaching a threshold.
In some embodiments, the signal transfer model may include an object information embedding layer for performing feature extraction on shape information and hair information of the measured object to obtain a head feature, and a signal determination layer for performing position information processing on the head feature, the initial noise signal, and the initial noise signal to obtain a target noise signal. The shape information may include, but is not limited to, the shape, size, etc. of the object, and the hair information may include, but is not limited to, the length of the hair, the hardness of the hair, the degree of bending of the hair, the condition of the hair oil, etc. of the object. The shape information and the hair information of the object to be measured can be determined by setting in advance.
As shown in fig. 10, the signal transfer model 930 may further include an object information embedding layer 930-1 and a signal determination layer 930-2 connected in sequence, the input of the object information embedding layer 930-1 may include shape information 1010 and hair information 1020 and output as a head feature 931, the input of the signal determination layer may include the head feature 931, an initial noise signal 910 and a position 920 of the initial noise signal, and the output may be a target noise signal 940. The object information embedding layer can be a naive Bayesian model, and the signal determining layer can be a deep neural network model.
In some embodiments, the object information embedding layer may be obtained by training: the training samples may include historical shape information and historical hair condition information of the test subject, and the label may include historical head features of the test subject, where the test subject may refer to a subject for obtaining data thereof to train the subject information embedding layer. The test object may be an organism or a non-organism, similar to the test object. The training samples and labels can be obtained by manually representing the relevant information of the test object. Multiple groups of training samples can be input into the initial object information embedding layer, a loss function is constructed based on the output of the initial object information embedding layer and the label, and parameters of the initial object information embedding layer are updated iteratively based on the loss function until preset conditions are met, so that the trained object information embedding layer is obtained. The preset conditions may include, but are not limited to, the loss function being less than a threshold, convergence, or the training period reaching a threshold.
In some embodiments, the layers may be determined by training the acquisition signal: the training sample may include historical head features, an initial test signal of the object to be tested, and a position of the initial test signal, and the label may include a collected test signal, and the aforementioned training sample and the label thereof may be obtained in a manner as described above in this specification. Multiple sets of training samples can be input into the initial signal determination layer, a loss function is constructed based on the output of the initial signal determination layer and the label, and parameters of the initial signal determination layer are updated iteratively based on the loss function until preset conditions are met, so that a trained signal determination layer is obtained. The preset conditions may include, but are not limited to, the loss function being less than a threshold, convergence, or the training period reaching a threshold.
It should be appreciated that there is a difference in the objects used in the training object information embedding layer corresponding to the training data of the signal determination layer. The trained object information embedding layer can extract the head characteristics of all objects (including the test object and the tested object), and the object information embedding layer is a model common to all tested objects, so that the object information embedding layer obtained by training based on the related data of the test object can extract the head characteristics of different tested objects. And the trained signal determination layer is used for determining the signal transfer relation of a certain measured object. As described above, when the measured objects are different, the corresponding signal transfer relationships are also different. Therefore, a signal determination layer obtained by training based on a measured object can only be used for determining the signal transfer relationship of the measured object. When the signal transfer relationship of another tested object needs to be determined, training can be performed based on the initial test signal of the tested object and the position of the initial test signal and the acquisition test signal on the basis of the trained object information embedding layer.
Some embodiments of the present description may determine the signal transfer relationship of the measured object more quickly and conveniently through the signal transfer model, so as to perform denoising processing on the acquired electroencephalogram signal. In addition, some embodiments of the present specification may further extract relevant features of the head of the object to be measured, and determine the influence of the difference of the relevant information of the head of the object to be measured on the signal transfer relationship of the object to be measured, so that the denoising processing on the acquired electroencephalogram signals is more accurate.
Fig. 11 is an exemplary flow chart illustrating the determination of a target noise signal according to some embodiments of the present description. In some embodiments, the flow 1100 may be performed by a second determination module.
In some embodiments, the signal transfer relationship may include a plurality of simple signal transfer relationships. The simple signal transfer relationship represents the signal change relationship of the first simple noise signal when the first simple noise signal is transmitted among all positions of the measured object. For more on simple signal transition relationships, see fig. 8 and its associated description. The first simple noise signal is obtained by transforming the original noise signal.
When the signal transfer relationship comprises a plurality of simple signal transfer relationships, the process 1100 may be performed to determine a target noise signal. As shown in fig. 11, the process 1100 may include the following steps:
step 1110 transforms the initial noise signal into a first simple noise signal of a plurality of different frequencies and intensities.
The first simple noise signal may be a simple signal transformed from the initial noise signal. For example, the first simple noise signal may include any one or a combination of a sine wave signal, a cosine wave signal, a square wave signal, and the like. The initial noise signal may be processed using fourier transform, laplace transform, discrete cosine transform, and the like to obtain a plurality of first simple noise signals of different frequencies and intensities.
Step 1120, for each first simple noise signal, processing the first simple noise signal based on a simple signal transfer relationship corresponding to the first simple noise signal, and determining a second simple noise signal corresponding to the first simple noise signal.
The second simple noise signal may refer to a noise signal when the first simple noise signal is propagated to other positions of the object to be measured.
In some embodiments, for each first simple noise signal, a second simple noise signal corresponding to the first simple noise signal at other locations may be determined based on the first simple noise signal, an input location of the first simple noise signal, and a simple signal transfer relationship. The transfer function of the input position to be transmitted to other positions can be determined according to the simple signal transfer relation and the input position of the first simple noise signal, and the second simple noise signal of other positions can be determined based on the transfer functions and the first simple noise signal.
In step 1130, the second simple noise signals are synthesized to obtain the target noise signal.
In some embodiments, for each location of the measured object, the second simple noise signals at the location may be synthesized to obtain a target noise signal at the location. The synthesis method may be an inverse transform of the transform method for processing the initial noise signal into the first simple noise signal to obtain the target noise signal. For example, when the initial noise signal is processed into the first simple noise signal based on the fourier transform, the respective second simple noise signals may be synthesized based on the inverse fourier transform to obtain the target noise signal.
Some embodiments of the present disclosure may conveniently obtain the target noise signal by using the simple noise signal and the simple signal transfer relationship, so as to simplify the operation and improve the calculation efficiency.
The embodiment of the specification provides a generation device for simulating acquired brain electrical signals, which comprises a processor, wherein the processor is used for executing the generation method for simulating the acquired brain electrical signals.
The embodiment of the present specification provides a computer-readable storage medium, where the aforementioned storage medium stores computer instructions, and after the computer reads the computer instructions in the storage medium, the computer executes the generation method for simulating the acquisition of electroencephalogram signals according to any one of the embodiments of the present specification.
The embodiment of the present specification further provides a collected electroencephalogram signal denoising device, which includes a processor, and the processor is used for executing the collected electroencephalogram signal denoising method according to any one of the embodiments of the present specification.
The embodiment of the present specification provides a computer-readable storage medium, where the storage medium stores computer instructions, and when a computer reads the computer instructions in the storage medium, the computer executes the method for denoising acquired electroencephalogram signals according to any one of the embodiments of the present specification.
It should be noted that the above descriptions about the respective flows are only for illustration and explanation, and do not limit the applicable scope of the present specification. Various modifications and changes to the individual processes may be made by those skilled in the art in light of the present disclosure. However, such modifications and variations are intended to be within the scope of the present description.
Having thus described the basic concept, it will be apparent to those skilled in the art that the foregoing detailed disclosure is to be regarded as illustrative only and not as limiting the present specification. Various modifications, improvements and adaptations to the present description may occur to those skilled in the art, although not explicitly described herein. Such modifications, improvements and adaptations are proposed in the present specification and thus fall within the spirit and scope of the exemplary embodiments of the present specification. Also, the description uses specific words to describe embodiments of the specification. Reference throughout this specification to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic described in connection with at least one embodiment of the specification is included. Therefore, it is emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, some features, structures, or characteristics of one or more embodiments of the specification may be combined as appropriate.
Additionally, the order in which the elements and sequences of the process are recited in the specification, the use of alphanumeric characters, or other designations, is not intended to limit the order in which the processes and methods of the specification occur, unless otherwise specified in the claims. While various presently contemplated embodiments of the invention have been discussed in the foregoing disclosure by way of example, it is to be understood that such detail is solely for that purpose and that the appended claims are not limited to the disclosed embodiments, but, on the contrary, are intended to cover all modifications and equivalent arrangements that are within the spirit and scope of the embodiments herein. For example, although the system components described above may be implemented by hardware devices, they may also be implemented by software-only solutions, such as installing the described system on an existing server or mobile device.
Similarly, it should be noted that in the foregoing description of embodiments of the present specification, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure aiding in the understanding of one or more of the embodiments. This method of disclosure, however, is not intended to imply that more features are required than are expressly recited in the claims. Indeed, the embodiments may be characterized as having less than all of the features of a single disclosed embodiment.
Numerals describing the number of components, attributes, etc. are used in some embodiments, it being understood that such numerals used in the description of the embodiments are modified in some instances by the use of the modifier "about", "approximately" or "substantially". Unless otherwise indicated, "about", "approximately" or "substantially" indicates that the number allows a variation of ± 20%. Accordingly, in some embodiments, the numerical parameters set forth in the specification and claims are approximations that may vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameter should take into account the specified significant digits and employ a general digit preserving approach. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the range in some embodiments of the specification are approximations, in specific embodiments, such numerical values are set forth as precisely as possible within the practical range.
For each patent, patent application publication, and other material, such as articles, books, specifications, publications, documents, etc., cited in this specification, the entire contents of each are hereby incorporated by reference into this specification. Except where the application history document is inconsistent or contrary to the present specification, and except where the application history document is inconsistent or contrary to the present specification, the application history document is not inconsistent or contrary to the present specification, but is to be read in the broadest scope of the present claims (either currently or hereafter added to the present specification). It is to be understood that the descriptions, definitions and/or uses of terms in the accompanying materials of this specification shall control if they are inconsistent or contrary to the descriptions and/or uses of terms in this specification.
Finally, it should be understood that the embodiments described herein are merely illustrative of the principles of the embodiments of the present disclosure. Other variations are also possible within the scope of this description. Thus, by way of example, and not limitation, alternative configurations of the embodiments of the present specification can be seen as consistent with the teachings of the present specification. Accordingly, the embodiments of the present description are not limited to only those explicitly described and depicted herein.

Claims (10)

1. A generation method for simulating an acquired electroencephalogram signal is characterized by comprising the following steps:
obtaining an intermediate simulated electroencephalogram signal based on the first preset parameter interval and the basic signal;
constructing a loss function based on the intermediate simulated electroencephalogram signal and the reference electroencephalogram signal;
iteratively updating the first preset parameter interval based on the loss function until a preset condition is met, and obtaining a first parameter set;
obtaining a noise-free simulated electroencephalogram signal based on the basic signal and the first parameter group, wherein the simulated electroencephalogram signal is used as a noise-free electroencephalogram signal in a human body to participate in analysis and research of the electroencephalogram signal;
obtaining a target noise signal based on the initial noise signal and the second parameter group, wherein the target noise signal is used as a noise signal in the collected electroencephalogram signal of the human body to participate in analysis and research of the electroencephalogram signal;
acquiring a first weight of the simulated brain electrical signal and a second weight of the target noise signal;
and obtaining a target analog acquisition electroencephalogram signal based on the analog electroencephalogram signal, the target noise signal, the first weight and the second weight, wherein the target analog acquisition electroencephalogram signal is used as the acquisition electroencephalogram signal to participate in the analysis and research of the electroencephalogram signal and reduce the acquisition of real electroencephalogram signals.
2. The method of claim 1, wherein the first parameter set includes a region of interest transfer matrix in which elements characterize a transfer relationship of signals as they propagate between different regions of interest, and a signal source transfer matrix in which elements characterize a transfer relationship of signals as they propagate between signal sources and electrode points in the same region of interest, wherein the different regions of interest represent different functional brain regions in a human brain;
the obtaining a noise-free simulated brain electrical signal based on the base signal and the first parameter group comprises:
for each signal source in the virtual brain model, determining a target basic signal of the signal source based on the region of interest transfer matrix and the basic signal emitted by the signal source;
aiming at each region of interest in the virtual brain model, determining an initial sub-simulation brain electrical signal corresponding to each region of interest based on the target basic signal and the signal source transfer matrix of each signal source in the region of interest;
and simulating a brain electrical signal based on the initial sub-simulation brain electrical signals corresponding to the interested areas to obtain the simulated brain electrical signal.
3. The method of claim 1, wherein the initial noise signal comprises a simulated brain noise signal and an electrode noise signal, and the second set of parameters comprises a region of interest transfer matrix in which elements characterize the transfer of the signal between different regions of interest and an electrode transfer matrix in which elements characterize the transfer of the signal between different electrode sites;
the obtaining a target noise signal based on the initial noise signal and the second parameter set comprises:
determining a first sub-noise signal based on the region of interest transfer matrix and the simulated brain noise signal;
determining a second sub-noise signal based on the electrode point transfer matrix and the electrode point noise signal;
obtaining the target noise signal based on the first sub-noise signal and the second sub-noise signal.
4. The method of claim 1, wherein the second parameter set is obtained based on a second preset parameter interval.
5. A system for generating an analog acquisition of an electroencephalogram signal, the system comprising:
a first obtaining module to:
obtaining an intermediate simulated electroencephalogram signal based on the first preset parameter interval and the basic signal;
constructing a loss function based on the intermediate simulated electroencephalogram signal and the reference electroencephalogram signal;
iteratively updating the first preset parameter interval based on the loss function until a preset condition is met, and obtaining a first parameter set;
obtaining a noise-free simulated electroencephalogram signal based on the basic signal and the first parameter group, wherein the simulated electroencephalogram signal is used as a noise-free electroencephalogram signal in a human body to participate in analysis and research of the electroencephalogram signal;
the second acquisition module is used for acquiring a target noise signal based on the initial noise signal and the second parameter group, wherein the target noise signal is used as a noise signal in the collected electroencephalogram signal of the human body to participate in analysis and research of the electroencephalogram signal;
the third acquisition module is used for acquiring a first weight of the simulated electroencephalogram signal and a second weight of the target noise signal;
and the fourth acquisition module is used for acquiring a target simulation acquisition electroencephalogram signal based on the simulation electroencephalogram signal, the target noise signal, the first weight and the second weight, wherein the target simulation acquisition electroencephalogram signal is used as the acquisition electroencephalogram signal to participate in analysis and research of the electroencephalogram signal and reduce acquisition of a real electroencephalogram signal.
6. The system of claim 5, wherein the first parameter set includes a region of interest transfer matrix in which elements characterize a transfer relationship of signals as they propagate between different regions of interest, and a signal source transfer matrix in which elements characterize a transfer relationship of signals as they propagate between a signal source and an electrode site in the same region of interest, wherein the different regions of interest represent different functional brain areas in a human brain;
the first obtaining module is further configured to:
for each signal source in the virtual brain model, determining a target basic signal of the signal source based on the region of interest transfer matrix and the basic signal emitted by the signal source;
aiming at each region of interest in the virtual brain model, determining an initial sub-simulation brain electrical signal corresponding to each region of interest based on the target basic signal and the signal source transfer matrix of each signal source in the region of interest;
and simulating a brain electrical signal based on the initial sub-simulation brain electrical signals corresponding to the interested areas to obtain the simulated brain electrical signal.
7. The system of claim 5, wherein the initial noise signal comprises a simulated brain noise signal and an electrode point noise signal, and the second parameter set comprises a region of interest transfer matrix in which elements characterize a transfer relationship of the signal as it propagates between different regions of interest and an electrode point transfer matrix in which elements characterize a transfer relationship of the signal as it propagates between different electrode points;
the second obtaining module is further configured to:
determining a first sub-noise signal based on the region of interest transfer matrix and the simulated brain noise signal;
determining a second sub-noise signal based on the electrode point transfer matrix and the electrode point noise signal;
obtaining the target noise signal based on the first sub-noise signal and the second sub-noise signal.
8. The system of claim 5, wherein the second set of parameters is obtained based on a second preset parameter interval.
9. A device for generating an analog acquired brain electrical signal, comprising a processor, characterized in that the processor is adapted to perform the method for generating an analog acquired brain electrical signal according to any one of claims 1 to 4.
10. A computer-readable storage medium storing computer instructions, wherein when the computer reads the computer instructions in the storage medium, the computer executes the method for generating analog acquired brain electrical signals according to any one of claims 1-4.
CN202210910794.XA 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals Pending CN115238745A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210910794.XA CN115238745A (en) 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202210910794.XA CN115238745A (en) 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals
CN202210659471.8A CN114742116B (en) 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
CN202210659471.8A Division CN114742116B (en) 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals

Publications (1)

Publication Number Publication Date
CN115238745A true CN115238745A (en) 2022-10-25

Family

ID=82287409

Family Applications (4)

Application Number Title Priority Date Filing Date
CN202210666384.5A Pending CN115034266A (en) 2022-06-13 2022-06-13 Collected electroencephalogram signal denoising method, system, device and medium
CN202210910733.3A Pending CN115186718A (en) 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals
CN202210659471.8A Active CN114742116B (en) 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals
CN202210910794.XA Pending CN115238745A (en) 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals

Family Applications Before (3)

Application Number Title Priority Date Filing Date
CN202210666384.5A Pending CN115034266A (en) 2022-06-13 2022-06-13 Collected electroencephalogram signal denoising method, system, device and medium
CN202210910733.3A Pending CN115186718A (en) 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals
CN202210659471.8A Active CN114742116B (en) 2022-06-13 2022-06-13 Generation method and system for analog acquisition of electroencephalogram signals

Country Status (1)

Country Link
CN (4) CN115034266A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116636817B (en) * 2023-07-26 2023-11-03 四川新源生物电子科技有限公司 Anesthesia depth evaluation method, anesthesia depth evaluation system, anesthesia depth evaluation device and storage medium

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006060727A2 (en) * 2004-12-03 2006-06-08 Aspect Medical Systems, Inc. System and method for eeg imaging of cerebral activity using electrode sets
US9730603B2 (en) * 2014-06-20 2017-08-15 Boston Scientific Scimed Inc. Medical devices for mapping cardiac tissue
CN110090017B (en) * 2019-03-11 2021-09-14 北京工业大学 Electroencephalogram signal source positioning method based on LSTM
US11996108B2 (en) * 2019-08-01 2024-05-28 Dolby Laboratories Licensing Corporation System and method for enhancement of a degraded audio signal
CN110879980B (en) * 2019-11-13 2023-09-05 厦门大学 Nuclear magnetic resonance spectrum denoising method based on neural network algorithm
CN110859600A (en) * 2019-12-06 2020-03-06 深圳市德力凯医疗设备股份有限公司 Method for generating electroencephalogram signal, storage medium and electronic equipment
CN111461204B (en) * 2020-03-30 2023-05-26 华南理工大学 Emotion recognition method based on electroencephalogram signals for game evaluation
CN112807000B (en) * 2021-02-04 2023-02-28 首都师范大学 Method and device for generating robust electroencephalogram signals
CN114190953A (en) * 2021-12-09 2022-03-18 四川新源生物电子科技有限公司 Training method and system of electroencephalogram signal noise reduction model for electroencephalogram acquisition equipment
CN114521904B (en) * 2022-01-25 2023-09-26 中山大学 Brain electrical activity simulation method and system based on coupled neuron group

Also Published As

Publication number Publication date
CN114742116B (en) 2022-09-02
CN115034266A (en) 2022-09-09
CN114742116A (en) 2022-07-12
CN115186718A (en) 2022-10-14

Similar Documents

Publication Publication Date Title
Krasoulis et al. Improved prosthetic hand control with concurrent use of myoelectric and inertial measurements
Li et al. EEG-based mild depression recognition using convolutional neural network
EP0699413B1 (en) Apparatus and method for analyzing information relating to physical and mental condition
Kohli et al. Removal of gross artifacts of transcranial alternating current stimulation in simultaneous EEG monitoring
US20060215883A1 (en) Biometric identification apparatus and method using bio signals and artificial neural network
Li et al. Emotion stimuli-based surface electromyography signal classification employing Markov transition field and deep neural networks
Yudhana et al. Human emotion recognition based on EEG signal using fast fourier transform and K-Nearest neighbor
Gu et al. Nonlinear modeling of cortical responses to mechanical wrist perturbations using the NARMAX method
CN112185493A (en) Personality preference diagnosis device and project recommendation system based on same
CN114742116B (en) Generation method and system for analog acquisition of electroencephalogram signals
Mouleeshuwarapprabu et al. Nonlinear vector decomposed neural network based EEG signal feature extraction and detection of seizure
Nasrolahzadeh et al. Analysis of mean square error surface and its corresponding contour plots of spontaneous speech signals in Alzheimer's disease with adaptive wiener filter
Raghu et al. Automated biomedical signal quality assessment of electromyograms: Current challenges and future prospects
Lopes et al. Ensemble deep neural network for automatic classification of eeg independent components
Nunez et al. A tutorial on fitting joint models of M/EEG and behavior to understand cognition
Liang et al. Identification of heart sounds with arrhythmia based on recurrence quantification analysis and Kolmogorov entropy
Chen et al. Research on AR‐AKF Model Denoising of the EMG Signal
CN115462755A (en) Pilot cognitive ability assessment method, system and storage medium
Chaudhary et al. Brain computer interface: a new pathway to human brain
Jaber et al. Elicitation hybrid spatial features from HD-sEMG signals for robust classification of gestures in real-time
Ihrke et al. Denoising and averaging techniques for electrophysiological data
Eremeev et al. Using convolutional neural networks for the analysis of nonstationary signals on the problem diagnostics vision pathologies
Shahzaib et al. Classification of forearm EMG signals for 10 motions using optimum feature-channel combinations
Herrera et al. Temperature influences at the myoelectric level in the upper extremities of the human body
Dashdamirov et al. Estimation of the Human Concentration using Echo State Networks.

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination