CN116570237A - A neural activity detection system under transcranial magnetoacoustic stimulation - Google Patents

Abstract

The present disclosure provides a nerve activity detection system under transcranial magnetoacoustic stimulation, including: a transcranial ultrasonic stimulation device, a magnetic field generating device, a frequency-domain near-infrared detection device, and a main control device; the transcranial ultrasonic stimulation device is set In order to send a target ultrasonic wave to the object to be measured to perform ultrasonic stimulation on the object to be measured; the magnetic field generating device is set to generate a target magnetic field at the position of the object to be measured to perform magnetic field Stimulation; the frequency-domain near-infrared detection device is set to perform near-infrared detection on the object to be tested under the ultrasonic stimulation and the magnetic field stimulation, to obtain near-infrared detection data of the object to be tested; the main The control device is set to obtain the parameter value of the preset nerve parameter according to the near-infrared detection data, wherein the nerve parameter reflects the nerve activity of the subject under test under the ultrasonic stimulation and the magnetic field stimulation parameters.

Description

A neural activity detection system under transcranial magnetoacoustic stimulation

technical field

The present disclosure relates to the technical field of transcranial magnetoacoustic stimulation, and more particularly, to a neural activity detection system under transcranial magnetoacoustic stimulation.

Background technique

Neuropsychiatric diseases have become an important factor affecting people's quality of life. At present, commonly used neuromodulation methods are divided into two categories: invasive and non-invasive. Invasive methods mainly include deep brain stimulation. Electrodes are implanted into the deep part of the brain, and neuromodulation is performed through micro-current stimulation to treat movement disorders and neurological diseases. This method has surgical risks and a low safety factor. Non-invasive methods mainly use physical energy such as sound, light, and electromagnetic energy for neuromodulation, and do not require invasive surgery. Currently, non-invasive neuromodulation includes transcranial magnetic stimulation, transcranial direct current stimulation, etc. These methods have insufficient stimulation depth. Issues with lower resolution etc.

Transcranial magnetoacoustic stimulation, as a new type of non-invasive neuromodulation method, has the advantages of high spatial resolution, non-invasiveness, and direct regulation of nerves, and has received more and more attention. The stimulation system introduces a magnetic field at the same time as ultrasonic stimulation, so that the ions in the nerve tissue are vibrated by the ultrasonic force in the uniform magnetic field and then subjected to the Lorentz force. The positive and negative ions move in opposite directions to generate induced current and electric field to achieve The purpose of neural regulation in the corresponding brain area.

However, in the prior art, the neuromodulation effect of the transcranial magnetoacoustic stimulation on the subject is unknown.

Contents of the invention

An object of the present disclosure is to provide a new technical solution of a transcranial magnetic acoustic stimulation detection system.

According to the first aspect of the present disclosure, a transcranial magnetoacoustic stimulation detection system is provided, including: a transcranial ultrasonic stimulation device, a magnetic field generation device, a frequency-domain near-infrared detection device, and a main control device;

The transcranial ultrasonic stimulation device is configured to emit target ultrasonic waves to the subject to be tested, so as to perform ultrasonic stimulation on the subject to be tested;

The magnetic field generating device is configured to generate a target magnetic field at the position of the object to be measured, so as to stimulate the object to be measured with a magnetic field;

The frequency-domain near-infrared detection device is configured to perform near-infrared detection on the object to be tested under the ultrasonic stimulation and the magnetic field stimulation, to obtain near-infrared detection data of the object to be measured;

The main control device is configured to obtain a preset parameter value of a nerve parameter according to the near-infrared detection data, wherein the nerve parameter reflects that the object under test is stimulated by the ultrasonic stimulus and the magnetic field. parameters of neural activity.

Optionally, the frequency-domain near-infrared detection device includes a signal transceiving module, a light emitting module and a light receiving module, the light emitting module includes at least one infrared light source, and the light receiving module includes a photodetector for receiving optical signals ;

The signal transceiving module is configured to output a first radio frequency signal of a first frequency and a control signal corresponding to each of the infrared light sources to the light transmitting module, and output a first radio frequency signal of a second frequency to the light receiving module. Two radio frequency signals; wherein, the phases of the first radio frequency signal and the second radio frequency signal are the same;

The light emitting module is configured to sequentially emit infrared light of a set wavelength through the at least one infrared light source according to the first radio frequency signal and the control signal;

The light receiving module is configured to perform heterodyne detection on the received reflected light and the second radio frequency signal to obtain a difference frequency voltage signal; the reflected light is reflected by the object to be measured to the photodetector infrared light;

The signal transceiving module is also configured to process the difference frequency voltage signal to obtain the near-infrared detection data.

Optionally, the light emitting module further includes a radio frequency selection switch unit, and a first drive unit corresponding to each of the infrared light sources,

The radio frequency selection switch unit includes a switch channel corresponding to each of the infrared light sources, and the radio frequency selection switch unit is configured to select a conductive switch channel according to the control signal, so that the first radio frequency signal transmitted to the corresponding first drive unit;

The first driving unit is configured to drive a corresponding infrared light source to emit the infrared light according to the first radio frequency signal.

Optionally, the light receiving module includes a heterodyne detection unit and a signal processing unit,

The photodetector is configured to perform photoelectric conversion processing on the reflected light to obtain a first signal;

The heterodyne detection unit is configured to perform heterodyne detection on the first signal and the second radio frequency signal to obtain a difference frequency current signal;

The signal processing unit is configured to perform current-voltage conversion processing on the difference frequency current signal to obtain the difference frequency voltage signal.

Optionally, the signal transceiving module includes a control unit, a first signal source unit, and a second signal source unit,

The control unit is configured to control the first signal source unit to output the first radio frequency signal, control the second signal source unit to output the second radio frequency signal, the first radio frequency signal and the second radio frequency signal The phase of the RF signal is the same;

The control unit is also configured to output the control signal to control the at least one infrared light source to emit light sequentially;

The signal transceiving module further includes an analog-to-digital conversion unit configured to perform analog-to-digital conversion processing on the difference frequency voltage signal to obtain the near-infrared detection data.

Optionally, when the main control device obtains the preset neural parameter value according to the near-infrared detection data, it is set to:

determining the optical parameters of the object to be measured under the corresponding infrared light source according to the near-infrared detection data corresponding to each infrared light source; or,

Determine the optical parameters of the object to be measured under the corresponding infrared light source according to the near-infrared detection data corresponding to each infrared light source; detect the blood of the object to be measured according to the optical parameters of the object to be measured under each infrared light source oxygen data;

Wherein, the optical parameters and the blood oxygen data are neural parameters reflecting the neural activity of the subject to be measured.

Optionally, the frequency-domain near-infrared detection device further includes a near-infrared probe, a detection optical fiber, and an emission optical fiber corresponding to each of the infrared light sources,

The first end of the emitting optical fiber is arranged on the near-infrared probe, and the second end of the emitting optical fiber is connected to the corresponding infrared light source, so that the infrared light emitted by the infrared light source is transmitted to the infrared light source through the corresponding emitting optical fiber. on the object to be measured that the near-infrared probe is in contact with;

The first end of the detection fiber is arranged on the near-infrared probe, and the second end of the detection fiber is connected to the photodetector, so that the reflected light is transmitted to the photodetector.

Optionally, the first end of the detection fiber and the first end of the emission fiber are arranged on the near-infrared probe so that the first end of each emission fiber is connected to the first end of the detection fiber. The distance between the ends is the same.

Near Infrared Probe

Optionally, the transcranial ultrasound stimulation device includes an ultrasound signal source, a power amplification module and an ultrasound transducer,

The ultrasonic signal source generates an ultrasonic driving signal;

The power amplification module is configured to amplify the ultrasonic drive signal;

The ultrasonic transducer is configured to convert the amplified ultrasonic driving signal into the target ultrasonic wave.

Optionally, the ultrasonic transducer includes a first ultrasonic transducer and a second ultrasonic transducer, the first surface of the first ultrasonic transducer is circular, and the first surface of the second ultrasonic transducer The second surface is ring-shaped, wherein the first surface is a surface for the first ultrasonic transducer to be in contact with the object to be measured, and the second surface is for the second ultrasonic transducer to be in contact with the object The surface in contact with the object to be measured.

Through the neural activity detection system of the embodiment of the present disclosure, near-infrared detection is performed on the subject under ultrasonic stimulation and magnetic field stimulation, and the near-infrared detection data of the subject is obtained. The parameter value of the neural parameters of the neural activity under the magnetic field stimulation can realize the detection of the neural activity of the subject under the transcranial magnetoacoustic stimulation, and then detect the neural regulation of the subject under the transcranial magnetoacoustic stimulation according to the parameter values of the neural parameters Effect.

Other features of the present disclosure and advantages thereof will become apparent through the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate the embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.

FIG. 1 shows a block diagram of a neural activity detection system under transcranial magnetoacoustic stimulation according to an embodiment of the present disclosure;

2 shows a block diagram of a transcranial ultrasound stimulation device according to an embodiment of the present disclosure;

Figure 3 shows a block diagram of an ultrasound signal source of an embodiment of the present disclosure;

Fig. 4 shows the block diagram of the power amplifying module of the embodiment of the present disclosure;

FIG. 5 shows a block diagram of a power amplifying unit of an embodiment of the present disclosure;

Figure 6 shows a block diagram of a power combiner of an embodiment of the present disclosure;

Figure 7a shows a schematic diagram of a first ultrasonic transducer of an embodiment of the present disclosure;

Figure 7b shows a schematic diagram of a second ultrasonic transducer of an embodiment of the present disclosure;

FIG. 8 shows a block diagram of a magnetic field generating device according to an embodiment of the present disclosure;

FIG. 9 shows a block diagram of a frequency-domain near-infrared detection device according to an embodiment of the present disclosure;

Fig. 10 shows a block diagram of a signal transceiving module of an embodiment of the present disclosure;

FIG. 11 shows a schematic diagram of a near-infrared probe according to an embodiment of the present disclosure;

FIG. 12 shows a schematic diagram of a near-infrared probe according to another embodiment of the present disclosure;

FIG. 13 shows a schematic diagram of a near-infrared detection device according to an embodiment of the present disclosure.

Detailed ways

Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that relative arrangements of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present disclosure unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and in no way intended as any limitation of the disclosure, its application or uses.

Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered part of the description.

In all examples shown and discussed herein, any specific values should be construed as exemplary only, and not as limitations. Therefore, other instances of the exemplary embodiment may have different values.

It should be noted that like numerals and letters denote like items in the following figures, therefore, once an item is defined in one figure, it does not require further discussion in subsequent figures.

Embodiments of the present disclosure provide a neural activity detection system under transcranial magnetoacoustic stimulation.

FIG. 1 shows a block diagram of a neural activity detection system under transcranial magnetoacoustic stimulation according to an embodiment of the present disclosure.

As shown in FIG. 1 , the nerve activity detection system 1000 under transcranial magnetic acoustic stimulation may include a transcranial ultrasonic stimulation device 1100 , a magnetic field generation device 1200 , a frequency-domain near-infrared detection device 1300 and a main control device 1400 .

The transcranial ultrasonic stimulation device 1100 is configured to emit target ultrasonic waves to the subject to be tested, so as to perform ultrasonic stimulation on the subject to be tested. Wherein, the target ultrasonic signal may be an ultrasonic signal whose frequency is the first target value.

The magnetic field generating device 1200 is configured to generate a target magnetic field at the position of the object to be measured, so as to stimulate the object to be measured with a magnetic field. Wherein, the target magnetic field may be a magnetic field whose magnetic field strength is the second target value.

The frequency-domain near-infrared detection device 1300 is configured to perform near-infrared detection on the object to be tested under ultrasonic stimulation and magnetic field stimulation, so as to obtain near-infrared detection data of the object to be tested.

The main control device 1400 is configured to obtain preset parameter values of nerve parameters according to the near-infrared detection data, wherein the nerve parameters are parameters reflecting the nerve activity of the subject under test under ultrasonic stimulation and magnetic field stimulation.

The first target value and the second target value in this embodiment may be respectively set in advance according to application scenarios or specific requirements.

Through the neural activity detection system of the embodiment of the present disclosure, near-infrared detection is performed on the subject under ultrasonic stimulation and magnetic field stimulation, and the near-infrared detection data of the subject is obtained. The parameter value of the neural parameters of the neural activity under the magnetic field stimulation can realize the detection of the neural activity of the subject under the transcranial magnetoacoustic stimulation, and then detect the neural regulation of the subject under the transcranial magnetoacoustic stimulation according to the parameter values of the neural parameters Effect.

In an example, the main control device 1400 may be provided by a host computer.

In one embodiment of the present disclosure, the transcranial ultrasonic stimulation device 1100, the magnetic field generating device 1200, and the frequency-domain near-infrared detection device 1300 are all in communication connection with the main control device 1400, and the main control device 1400 is configured to set the transcranial ultrasonic stimulation For the ultrasonic parameters of the device 1100 , set the magnetic field parameters of the magnetic field generating device 1200 , and set the near-infrared light source parameters of the frequency-domain near-infrared detection device 1300 .

Wherein, the ultrasound parameters may include the frequency of the target ultrasound signal, the polarity of the fundamental wave, the frequency of the fundamental wave, the amplitude of the fundamental wave, the number of fundamental waves, the pulse period, the number of pulses, the stimulation period, the number of stimulations, and the like. The magnetic field parameters may include the magnitude and direction of the drive current of the electromagnet. The parameters of the near-infrared light source may include the emission wavelength and emission duration of the near-infrared light source.

Further, the main control device 1400 can also be configured to control the synchronization of ultrasonic stimulation, magnetic field stimulation and near-infrared detection. Specifically, the main control device 1400 may control the transcranial ultrasound stimulation device 1100 , the magnetic field generation device 1200 and the frequency-domain near-infrared detection device 1300 to work synchronously.

In one embodiment of the present disclosure, as shown in FIG. 2 , a transcranial ultrasound stimulation device 1100 may include an ultrasound signal source 1110 , a power amplification module 1120 and an ultrasound transducer 1130 .

The ultrasonic signal source 1110 is configured to generate an ultrasonic drive signal of electrical energy.

The power amplification module 1120 is configured to amplify the ultrasonic driving signal generated by the ultrasonic signal source 1110 to drive the ultrasonic transducer 1130 with maximum power.

The ultrasonic transducer 1130 is configured to convert the ultrasonic driving signal of electrical energy amplified by the power amplification module 1120 into ultrasonic waves of acoustic energy.

The ultrasonic signal source 1110 has multiple working modes and can generate abundant ultrasonic signals, especially a multi-mode ultrasonic driving signal composed of multiple stimuli with adjustable parameters and controllable period.

The range of modifiable ultrasonic parameters and their step values in this embodiment are as follows, fundamental wave polarity: positive or negative, fundamental wave frequency F: 0.2MHz～8MHz (step value is 0.01MHz), fundamental wave amplitude Vpp: 0.01V～20V (step value 0.01V), number of fundamental waves N: 1～50000 (step value 1), pulse period PRT: 100us～10s (step value 100us), pulse number M: 1～20000 (step value is 1), stimulation period SRT: 1s～60s (step value is 1s), stimulation number C: 1～20000 (step value is 1).

In an embodiment of the present disclosure, as shown in FIG. 3 , the ultrasonic signal source 1110 may include a control unit 1111 , a logic control unit 1112 , a digital-to-analog conversion unit 1113 , a low-pass filter unit 1114 and an amplitude control unit 1115 .

The control unit 1111 is configured to receive the ultrasonic parameter setting command issued by the main control device 1400 and transmit it downward. Specifically, the control unit 1111 may communicate with the main control device 1400 to set ultrasound parameters and working modes.

The logic control unit 1112 is configured to receive commands transmitted by the control unit 1111 and generate digital signals and gain control signals.

The digital-to-analog conversion unit 1113 is configured to convert the digital signal generated by the logic control unit 1112 into a ladder-shaped first analog signal.

The low-pass filtering unit 1114 is configured to filter the stepped first analog signal and transform it into a smooth second analog signal.

The amplitude control unit 1115 is configured to control the amplitude of the second analog signal according to the gain control signal generated by the logic control unit 1112, so as to realize the output of the ultrasonic driving signal satisfying the parameter setting command.

In an embodiment of the present disclosure, as shown in FIG. 3 , the ultrasonic signal source 1110 may further include a status indicating module 1116 . The logic control module 1112 is configured to receive a command transmitted by the main control module 1111 and generate a status indicating signal. The state indicating module 1116 is configured to indicate the power-on state of the ultrasonic signal source 1110 and the working state of the generated ultrasonic wave according to the state indicating signal generated by the logic control module 1112 .

In an embodiment of the present disclosure, as shown in FIG. 4 , the power amplifying module 1120 may include a preamplifying unit 1121, a plurality of one-to-four power splitters 1122, a power amplifying unit 1123 and a four-in-one power combiner 1124, Specifically, it may be as shown in FIG. 4 .

The working process of the power amplification module 1120 can be as follows: the gain of the preamplifier unit 1121 is 27dB; the power divider 1122 divides the ultrasonic driving signal from one path into four paths, and the four paths of signals are redistributed into sixteen paths of signals by the power divider 1122 ; The power amplifying unit 1123 respectively amplifies the signals of sixteen channels with a gain of 13dB; the power combiner 1124 finally combines the signals from sixteen channels into four channels, and then combines the signals from four channels into one channel.

Among them, the specifications of the power amplifier module 1120 are as follows: the operating frequency is 100kHz-8MHz, the linear gain is 40dB, the maximum output power can reach 200W, the harmonic suppression ratio can be 40dBc, the input and output impedance is 50 ohms, and the input standing wave ratio is less than 1.2.

The power amplifying unit 1123 may be a push-pull linear power amplifying circuit, and its circuit structure may be as shown in FIG. 5 . The working process of the power amplifying unit 1123 can be as follows: the input line number first passes through the 1:1 transmission line transformer 501 and the matching impedance 502 to convert the single-ended input signal into two signal voltages with equal magnitude and opposite polarity, respectively exciting two MOS tubes 503 and 504. The two MOS transistors each amplify the half-period signal within one signal period and work in a complementary state. After being amplified by the MOS transistors, the signals of 503 and 504 pass through the transmission line transformer 505 with an impedance ratio of 1:1 and finally output single-ended signals. The 28V power supply provides voltage for the drain of the MOS transistor through the transmission line transformer 501 . The characteristic impedances of the two transmission line transformers 501 and 505 are both 50 ohms, which are used to achieve impedance matching between the input signal and the gates of the MOS transistors 503 and 504 and the drains of the MOS transistors 503 and 504 and the output signal.

The power divider 1122 and the power combiner 1124, as a general passive device, are widely used in wireless communication and various radar devices. Its main function is to divide the input signal at one end into multi-port output. The input and output ports can be reciprocated, and the multi-port output can also be used as multi-port input. Therefore, the same circuit can be used as both a power divider and a power combiner. device. The design methods of the power combiner and the power divider are the same, and the circuit of the designed four-in-one power combiner 1124 may be as shown in FIG. 6 .

The working process of the four-in-one power combiner 1124 is as follows: the input impedance of the four input ports is 50Ω, and the output impedance of the output port 608 is also 50Ω. The input ports require the input of equivalent in-phase power signals. Input port 1 and input port 2 are composed of input matching resistors 601 and transmission line transformers 602. The two-in-one power combining module is composed of input port 3 and input port 4. Input matching resistors 603 and transmission line transformers 604 2-in-1 power combining module, at this time, input the synthesized two-way signal into the 2-in-1 power combining module composed of matching resistor 605 and transmission line transformer 606 to obtain the synthesized signal of four input signals, which becomes a single terminal output, and the output impedance is 12.5Ω, while the output impedance of the power amplifier module is 50Ω. At this time, after the 4:1 impedance of the transmission line transformer 607 changes, the output impedance becomes 50Ω, and the output port 608 is a single-ended output, completing a four-in-one power combiner.

In one embodiment of the present disclosure, the ultrasonic transducer 1130 includes a first ultrasonic transducer 1131 and a second ultrasonic transducer 1132, and the focal lengths of the first ultrasonic transducer 1131 and the second ultrasonic transducer 1132 may be the same .

Further, the first surface of the first ultrasonic transducer 1131 is circular, as shown in FIG. 7a, and the second surface of the second ultrasonic transducer 1132 is circular, as shown in FIG. 7b. Wherein, the first surface is the surface for the first ultrasonic transducer to contact with the object to be measured, and the second surface is the surface for the second ultrasonic transducer to contact with the object to be measured.

Specifically, as shown in Figure 7a, the center of the first ultrasonic transducer 1131 is not open, and its outer diameter is d1; as shown in Figure 7b, the center of the second ultrasonic transducer 1132 is open, its outer diameter is d3, and the opening diameter is d2, and d1<d2<d3.

In one example, the outer diameter of the first ultrasonic transducer 1131 is 20 mm, the outer diameter of the second ultrasonic transducer 1132 is 64 mm, and the central opening diameter is 30 mm.

In this embodiment, in the case where the first ultrasonic transducer 1131 is used to emit ultrasonic waves to the object to be measured, the near-infrared detection. In the case where the second ultrasonic transducer 1132 is used to emit ultrasonic waves to the object to be tested, near-infrared detection may be performed on the area inside the central opening of the second ultrasonic transducer 1132 on the object to be tested.

In an embodiment of the present disclosure, as shown in FIG. 8 , the magnetic field generating device 1200 may include an electromagnet 1210 and a bipolar constant current source module 1220 .

The bipolar constant current source module 1220 is configured to output a driving current to the electromagnet 1210 so that the electromagnet 1210 generates a magnetic field under the action of the driving current.

As shown in FIG. 8 , the bipolar constant current source module 1220 may include a power supply unit 1221 and a dynamic digital controller 1222 . The power supply unit 1221 is configured to output driving current to the electromagnet 1210 , and the dynamic digital controller 1222 is configured to adjust the current magnitude of the driving current output by the power supply unit 1221 .

Specifically, the dynamic digital controller 1222 may be controlled by the main control device 1400 , so that the dynamic digital controller 1222 adjusts the magnitude of the driving current output by the power supply unit 1221 .

In this embodiment, by adjusting the magnitude and direction of the driving current, the direction and strength of the magnetic field generated by the electromagnet 1210 can be controlled, so that the electromagnet 1210 can generate a smooth and stable target magnetic field.

In addition, the bipolar constant current source module 1220 also includes a gauss meter for detecting the actual magnetic field strength of the magnetic field generated by the electromagnet 1210 in real time. The power supply unit 1221 can adjust the magnitude of the driving current according to the actual magnetic field strength, so that the actual magnetic field strength of the magnetic field generated by the electromagnet under the action of the driving current is stable to the set magnetic field strength, thereby realizing closed-loop control.

Further, as shown in FIG. 8 , the magnetic field generating device 1200 may further include a circulating water cooling module 1230 . The circulating water cooling module 1230 may include a water cooler 1231 and a temperature controller 1232. The water cooler 1231 is used to cool the electromagnet 1210 to keep the temperature of the electromagnet 1210 constant and the output magnetic field stable. The temperature controller 1232 can control the water temperature of the water cooler 1231, and its control range can be 5°C-35°C, accurate to 0.1°C.

In an embodiment of the present disclosure, as shown in FIG. 9 , the frequency-domain near-infrared detection device 1300 may include a signal transceiving module 1310 , a light transmitting module 1320 and a light receiving module 1330 . Wherein, the light emitting module 1320 includes at least one infrared light source 1321, and the light receiving module 1330 includes a photodetector 1331 for receiving reflected light, which is infrared light reflected by the object to be measured to the photodetector 1331.

The signal transceiving module 1310 is configured to output a first radio frequency signal of a first frequency and a control signal corresponding to each infrared light source 1321 to the light emitting module 1320 , and output a second radio frequency signal of a second frequency to the light receiving module 1330 . Wherein, the phases of the first radio frequency signal and the second radio frequency signal are the same.

The light emitting module 1320 is configured to sequentially emit infrared light of a set wavelength through at least one infrared light source 1321 according to the first radio frequency signal and the control signal.

The light receiving module 1330 is configured to perform heterodyne detection on the received reflected light and the second radio frequency signal to obtain a difference frequency voltage signal. Wherein, the reflected light is the infrared light reflected by the object to be measured to the photodetector 1331 .

The signal transceiving module 1310 is also configured to process the difference frequency voltage signal to obtain near-infrared detection data.

Through the frequency-domain near-infrared detection device of this embodiment, the near-infrared detection can be performed on the target object, and the near-infrared detection data of the object to be measured can be obtained, and then the neural activity of the object to be measured, the change of the scattering rate of the nervous tissue and the neural electrical activity can be detected. Synchronization occurs, therefore, neural parameters can directly reflect neural activity, and its time resolution can reach milliseconds. It has the advantages of low cost, high time resolution, no side effects and harm, and unlimited requirements for the tested objects.

In an embodiment of the present disclosure, as shown in FIG. 10 , the signal transceiving module 1310 includes a control unit 1311 , a first signal source unit 1312 , and a second signal source unit 1313 .

The control unit 1311 is configured to control the first signal source unit 1312 to output a first radio frequency signal, control the second signal source unit 1313 to output a second radio frequency signal, and output a control signal to control at least one infrared light source 1321 to emit light sequentially.

In this embodiment, the first radio frequency signal and the second radio frequency signal have the same phase and different frequencies. For example, the frequencies of the first radio frequency signal and the second radio frequency signal may be 100 MHz and 100.005 MHz respectively, or the frequencies of the first radio frequency signal and the second radio frequency signal may be 120 MHz and 120.005 MHz respectively.

In one example, the output power of the first signal source unit 1312 and the second signal source unit 1313 can be adjusted, the adjustment range is -3dBm～+26dBm, the adjustment step value is 0.25dB, and the frequency accuracy of the output radio frequency signal is ± 3*10^(-6)*center frequency.

Further, as shown in FIG. 10 , the signal transceiving module 1310 may further include a clock unit 1314 configured to provide a clock signal to each functional unit of the signal transceiving module 1310 . Each functional unit of the signal transceiver module 1310 includes any one or more of a control unit 1311, a first signal source unit 1312, a second signal source unit 1313, a clock unit 1314, an analog-to-digital conversion unit 1315, and a programmable operational amplifier circuit 1316 .

Still further, the first signal source unit 1312 may generate the first radio frequency signal according to the clock signal, and the second signal source unit 1313 may generate the second radio frequency signal according to the clock signal.

In one embodiment of the present disclosure, as shown in FIG. 10 , the clock unit 1314 may include a crystal oscillator 13141 , a switch subunit 13142 , a clock buffer 13143 and an external clock input terminal 13144 for inputting an external clock signal.

A crystal oscillator 13141 is set up to generate the internal clock signal. For example, the crystal oscillator 13141 can generate a 12.8MHz internal clock signal.

Both the crystal oscillator 13141 and the external clock input terminal 13144 are connected to the input terminal of the clock buffer 13143 through the switch subunit 13142 .

The clock buffer 13143 is configured to output the input internal clock signal or external clock signal through the output terminal corresponding to the functional unit, so as to provide the clock signal to the functional unit.

In this embodiment, the clock buffer 13143 may include an output terminal that corresponds to each functional unit that needs a clock signal in the signal transceiver module 1310, and the clock signal input through the input terminal (that is, an internal clock signal or an external clock signal) A clock signal) is output to a corresponding functional unit through each output terminal, so as to provide a clock signal for each functional unit.

Further, the clock buffer 13143 may also include other output terminals, which may be connected to external functional modules of the signal transceiving module 1310, so that the external functional modules obtain the clock signal used by the signal transceiving module 1310 to The external functional modules and the signal transceiving module 1310 are kept in clock synchronization.

In one embodiment of the present disclosure, the switch subunit 13142 may be a single pole double throw switch. Specifically, the common end of the SPDT switch is connected to the input end of the clock buffer 13143 , and the other two ends of the SPDT switch are respectively connected to the crystal oscillator 13141 and the external clock input end 13144 .

In another embodiment of the present disclosure, the switch subunit 13142 may further include a first switch and a second switch. Specifically, the crystal oscillator 13141 may be connected to the input end of the clock buffer 13143 through a first switch, and the external clock input end 13144 may be connected to the input end of the clock buffer 13143 through a second switch.

In one embodiment of the present disclosure, the control unit 1311 may control the conduction state of the switch subunit 13142 to select the internal clock signal or the external clock signal to be transmitted to the input terminal of the clock buffer 13143 .

In an embodiment of the present disclosure, as shown in FIG. 10 , the first signal source unit 1312 may include a signal generation circuit 13121 and a programmable gain amplification circuit 13122 .

The signal generation circuit 13121 is configured to generate the first radio frequency signal according to the clock signal.

The programmable gain amplification circuit 13122 is configured to amplify the first radio frequency signal.

In one example, the signal generating circuit 13121 may include a first phase-locked loop chip and a second filter.

The first phase-locked loop chip is configured to generate a first radio frequency signal according to the clock signal. The second filter is configured to filter the first radio frequency signal.

The first phase-locked loop chip of this embodiment may be a fractional N phase-locked loop chip integrating a VCO (oscillating circuit), and the clock reference input port of the fractional-N phase-locked loop chip integrating a VCO may be an output of a clock buffer 13143 The port of the logic control part is connected to the control unit 1311, so that the control unit 1311 can control the phase-locked loop and the oscillation circuit inside the fractional-N phase-locked loop chip with integrated VCO, so that the fractional-N phase-locked loop with integrated VCO The chip is capable of outputting a first radio frequency signal of a first frequency.

The second filter may be a band-pass filter, and the band-pass filter filters the first radio frequency output by the phase-locked loop chip, which can reduce external interference received by the first radio frequency signal output by the signal generating circuit 13121 .

In one embodiment of the present disclosure, the programmable gain amplification circuit 13122 may include a first programmable gain amplification subunit and a first temperature sensor. The first programmable gain amplification subunit is configured to amplify the first radio frequency signal. The first temperature sensor is configured to collect the first temperature of the programmable gain amplifying subunit, and transmit the first temperature to the control unit, so that the control unit can monitor and protect the first programmable gain amplifying subunit according to the first temperature.

Specifically, the first programmable gain amplifying subunit may include a first programmable gain attenuator chip and a first amplifier, and the control unit may control the first programmable gain attenuator chip and the first amplifier to realize the first radio frequency signal The gain is adjustable. Among them, the gain adjustment range is -31.75dB～0dB, and the step value is 0.25dB.

In an embodiment of the present disclosure, as shown in FIG. 10 , the second signal source unit 1313 may include a signal generation circuit 13131 and a programmable gain amplification circuit 13132 .

The signal generating circuit 13131 is configured to generate a second radio frequency signal according to the clock signal.

The programmable gain amplification circuit 13132 is configured to amplify the second radio frequency signal.

In one example, the signal generating circuit 13131 may include a second phase-locked loop chip and a third filter.

The second phase-locked loop chip is configured to generate a second radio frequency signal according to the clock signal. The third filter is configured to filter the second radio frequency signal.

The second phase-locked loop chip of this embodiment can be a fractional-N phase-locked-loop chip integrating a VCO (oscillating circuit), and the clock reference input port of the fractional-N phase-locked loop chip integrating a VCO can be an output of a clock buffer 13143 The port of the logic control part is connected to the control unit 1311, so that the control unit 1311 can control the phase-locked loop and the oscillation circuit inside the fractional-N phase-locked loop chip with integrated VCO, so that the fractional-N phase-locked loop with integrated VCO The chip can output a second radio frequency signal of a second frequency.

The third filter may be a band-pass filter, and the band-pass filter performs filtering processing on the first radio frequency output by the phase-locked loop chip, so as to reduce external interference received by the second radio frequency signal output by the signal generating circuit 13131 .

In one embodiment of the present disclosure, the programmable gain amplification circuit 13132 may include a second programmable gain amplification subunit and a second temperature sensor. The second programmable gain amplification subunit is configured to amplify the second radio frequency signal. The second temperature sensor is configured to collect the second temperature of the second programmable gain amplifying subunit, and transmit the second temperature to the control unit, so that the control unit can monitor and protect the programmable gain amplifying subunit according to the second temperature.

Specifically, the second programmable gain amplifying subunit may include a second programmable gain attenuator chip and a second amplifier, and the control unit may control the second programmable gain attenuator chip and the second amplifier to realize the second radio frequency signal The gain is adjustable. Among them, the gain adjustment range is -31.75dB～0dB, and the step value is 0.25dB.

In one embodiment of the present disclosure, as shown in FIG. 10 , the signal transceiving module 1310 may also include an analog-to-digital conversion unit 1315, and the analog-to-digital conversion unit 1315 is configured to perform analog-to-digital conversion processing on the difference frequency voltage signal to obtain near-infrared Test data.

Further, as shown in FIG. 10 , the signal transceiver module 1310 may also include a programmable operational amplifier circuit 1316, the programmable operational amplifier circuit 1316 is connected between the signal receiving module 1330 and the analog-to-digital conversion unit 1315, and the programmable operational amplifier circuit 1316 It is set to amplify the difference frequency voltage signal.

In this embodiment, the programmable operational amplifier circuit 1316 may include a signal relay, a resistor network chip, and an operational amplifier chip. One end of the signal relay is connected to the differential frequency voltage signal input from the outside, and the control port is connected to the control unit. The switch of the high and low level control signal relay is used in conjunction with the resistor network chip and the operational amplifier chip to realize the amplification gain control of the input difference frequency voltage signal. The input port of the analog-to-digital conversion unit 1315 is connected to the output end of the programmable operational amplifier circuit 1316, and the control port is connected to the control unit to realize the control of the analog-to-digital conversion unit 1315 by the control unit, and the amplified by the programmable operational amplifier circuit 1316 The difference frequency voltage signal is processed by analog-to-digital conversion, and the processed near-infrared detection data is transmitted to the control unit through SPI communication.

Still further, the signal transceiving module 1310 may also include a temperature sensor, which is configured to detect the third temperature of the programmable operational amplifier circuit 1316, and transmit the third temperature to the control unit for the control unit to adjust the programmable operation Amplifying circuit 1316 monitors and protects.

In an embodiment of the present disclosure, the signal transceiving module 1310 may further include a voltage adjustment unit 1317, and the voltage adjusting unit 1317 is configured to perform voltage adjustment on the power supply voltage provided by the frequency-domain near-infrared detection device 1300 to the signal transceiving module 1310 to supply power to each functional unit of the signal transceiving module 1310 . Each functional unit of the signal transceiver module 1310 includes any one or more of a control unit 1311, a first signal source unit 1312, a second signal source unit 1313, a clock unit 1314, an analog-to-digital conversion unit 1315, and a programmable operational amplifier circuit 1316 .

In this embodiment, the voltage adjustment unit 1317 can use a radio frequency low dropout linear regulator (radio frequency LDO) to provide the frequency domain near-infrared detection device 1300 to the 12V power supply voltage of the signal transceiving module 1310, and convert it into the power supply voltage of each functional unit. The required voltage value provides a stable voltage output.

In one example, the programmable operational amplifier circuit is powered by 5V, the VDDCP_5V port of the fractional-N phase-locked loop chip integrated with VCO is powered by 5V, and the RVDD_3.3V port of the fractional-N phase-locked loop chip integrated with VCO is powered by 3.3V. The amplifier in the programmable gain amplifying subunit is powered by 8V, and the programmable gain attenuator chip in the programmable gain amplifying subunit is powered by 3.3V.

In one embodiment of the present disclosure, as shown in FIG. 10 , the signal transceiving module 1310 can also include a communication interface module 1318, and the communication interface module 1318 can include a 26P fast I/O port 13181 up to 80MHz, JIAG/SWD/ISP Download interface 13182, USB-B port 13183 and serial port 13184. The signal transceiving module 1310 can perform data communication with other functional modules of the frequency-domain near-infrared detection device 1300 and other functional devices of the nerve activity detection system through the communication interface module 1318 . Wherein, other functional modules of the frequency-domain near-infrared detection device 1300 may include a light emitting module and/or a light receiving module, and other functional devices of the nerve activity detection system may include a transcranial ultrasonic stimulation device, a magnetic field generating device, a main control device, another Any one or more of a frequency-domain near-infrared detection device.

Among them, 26P fast I/O port 13181 can output TTL control signal. The JIAG/SWD/ISP download interface 13182 is mainly responsible for programming the control program into the control unit. The USB-B port 13183 is used for data communication with the host device. The serial port 13184 can be selected as the port for data interaction.

In one embodiment of the present disclosure, the surface of the circuit board of the signal transceiving module 1310 is provided with bare copper, and the bare copper is connected to the ground terminal of the signal transceiving module 1310 . In this way, mutual interference between functional units in the signal transceiving module 1310 can be avoided, and chips in the signal transceiving module 1310 can also be dissipated.

In one embodiment of the present disclosure, the circuit board of the signal transceiver module 1310 may be arranged in a metal casing, so that the metal casing covers the circuit board of the signal transceiver module 1310, which can enhance the heat dissipation capability and anti-interference of the signal transceiver module 1310 ability.

Through the signal transceiving device of the embodiment of the present disclosure, two radio frequency signal sources that can output the same phase, adjustable and stable output power are provided for the near-infrared detection system, and an analog-to-digital conversion unit with high sampling accuracy and sampling rate can be The use of redundant equipment in the near-infrared detection system is reduced, and the volume of the near-infrared detection system is reduced.

In an embodiment of the present disclosure, as shown in FIG. 9 , the light emitting module 1320 may further include a radio frequency selection switch unit 1322 and a first driving unit 1323 corresponding to each infrared light source.

The radio frequency selection switch unit 1322 includes a switch channel corresponding to each infrared light source 1321, and the radio frequency selection switch unit 1322 is configured to select the conduction switch channel according to the control signal, so as to transmit the first radio frequency signal to the corresponding first driver Unit 1323.

The first driving unit 1323 is configured to drive the corresponding infrared light source 1321 to emit infrared light according to the first radio frequency signal.

Specifically, the input terminal of the radio frequency selection switch unit 1322 is used to receive the first radio frequency signal output by the signal transceiving module 1310, the radio frequency selection switch unit 1322 includes an output terminal corresponding to each first driving unit 1323, and each output terminal It is connected to the input end of the corresponding first driving unit 1323 , and the output end of each first driving unit 1323 is connected to the corresponding infrared light source 1321 .

The control terminal of the radio frequency selection switch unit 1322 is used to receive the control signal output by the signal transceiver module 1310, so that the signal transceiver module 1310 controls the switch state of each switch channel in the radio frequency selection switch unit 1322 according to the control signal.

In one embodiment of the present disclosure, when the first driving unit 1323 drives the corresponding infrared light source to emit infrared light according to the first radio frequency signal, it is configured to: generate a DC driving signal, and modulate the DC driving signal and the first radio frequency signal , drive the corresponding infrared light source to emit infrared light according to the modulated signal.

Further, the first drive unit 1323 may include a constant current source circuit and a DC drive circuit, and the constant current source circuit is configured to perform voltage-to-current conversion processing on the first radio frequency signal to obtain an AC drive signal, and output an AC drive signal to the corresponding infrared light source. Drive signal; the DC drive circuit is configured to output a DC drive signal to the corresponding infrared light source under the condition that the control signal controls its own operation.

The infrared light source 1321 emits infrared light under the drive of the DC driving signal and the AC driving signal.

The enabling end of the light source driving circuit 1323 is used to receive the control signal output by the signal transceiver module 1310. When the control signal is used to control the conduction of the switch channel corresponding to itself in the radio frequency selection switch unit 1322, the control signal also controls the The light source driving circuit 1323 works. When the control signal is used to control the switch channel corresponding to itself in the radio frequency selection switch unit 1322 to be disconnected, the control signal also controls the light source driving circuit 1323 to not work.

In one embodiment of the present disclosure, since the laser diode has the advantages of small size, light weight, low power consumption, simple driving circuit, convenient modulation, mechanical shock resistance and vibration resistance, the infrared light source can be a laser diode, and its wavelength Can be 690nm or 830nm.

Furthermore, the laser diode can return a feedback signal to the DC driving circuit during operation, so that the DC driving circuit can realize constant power control of the laser diode.

In this embodiment, the method of controlling the infrared light source 1321 by the signal transceiving module 1310 may be realized by time division multiplexing.

In one example, the signal transceiving module 1310 can control the light emitting module 1320 to turn on an infrared light source every set time, so that within a cycle, the infrared light sources in the light emitting module 1320 emit infrared light in turn, and each The light-emitting time of the infrared light source is a set time. For example, the light emitting module 1320 includes 4 infrared light sources, and the set duration is 5 milliseconds. Then, within a cycle, the 4 infrared light sources emit infrared light of corresponding wavelengths sequentially, and the duration of a cycle is 20 milliseconds.

In one embodiment of the present disclosure, the light receiving module 1330 further includes a heterodyne detection unit 1332 and a signal processing unit 1333 .

The photodetector 1331 is configured to perform photoelectric conversion processing on the reflected light to obtain a first signal. The heterodyne detection unit 1332 is configured to perform heterodyne detection on the first signal and the second radio frequency signal to obtain a difference frequency current signal. The signal processing unit 1333 is configured to convert and process the outer differential current information current and voltage to obtain a differential frequency voltage signal.

In an embodiment of the present disclosure, the light receiving module 1330 further includes a second driving unit configured to drive the photodetector 1331 to work. Specifically, the second driving unit may provide negative high voltage to the photodetector 1331 to make the photodetector 1331 work.

In one embodiment, the photodetector 1331 may use a photomultiplier tube. Photomultiplier tubes have the advantages of sensitive and accurate detection. The working principle of the photomultiplier tube is: the reflected light illuminates the photomultiplier tube, and its cathode will generate photoelectrons, which will be amplified by multi-stage dynodes to generate a current signal, that is, the first signal. Therefore, the sensitivity of the photomultiplier tube is extremely high up to the photon level, and it has excellent spectral response, linear dynamic range and time response. The photoelectric converter can ensure the reliability of the system detection results.

The photomultiplier tube cooperates with the input negative high voltage to realize the detection of reflected light and complete the conversion from optical signal to electrical signal.

Further, the light receiving module 1330 may further include a first filter, which is configured to filter the difference frequency voltage signal and transmit it to the signal transceiving module 1310 . In this way, the signal-to-noise ratio of the system can be improved.

Still further, the first filter may be a band-pass filter.

In one embodiment of the present disclosure, in order to eliminate the interference of high-frequency signals, it is possible to integrate all parts of the circuits of the light receiving module 1330 into a shielding box with a shielding effect, and use standard interfaces and cables to communicate with other modules. connected to improve the anti-interference ability of the light receiving module 1330, thereby improving the anti-interference ability of the frequency-domain near-infrared detection device.

In an embodiment of the present disclosure, the frequency-domain near-infrared detection device 1300 may further include an air cooling module, which is configured to dissipate heat from the signal transceiving module 1310 that generates a lot of heat.

Further, the air cooling module can also perform heat dissipation for the light emitting module 1320 and the light receiving module 1330 .

In an embodiment of the present disclosure, the frequency-domain near-infrared detection device 1300 may further include a power module, and the power module may supply power to the signal transceiving module 1310 , the light transmitting module 1320 and the light receiving module 1330 .

In an embodiment of the present disclosure, the frequency-domain near-infrared detection device 1300 may further include a near-infrared probe, a detection optical fiber, and an emission optical fiber corresponding to each infrared light source. The first end of the emitting fiber is arranged on the near-infrared probe, and the second end of the emitting fiber is connected to the corresponding infrared light source, so that the infrared light emitted by the infrared light source is transmitted to the object to be measured by the near-infrared probe through the corresponding emitting fiber. Specifically, the first end of the emission fiber connected to each infrared light source may be set at the corresponding emission position of the near-infrared probe.

The first end of the detection fiber is arranged on the near-infrared probe, and the second end of the detection fiber is connected with the photodetector, so that the reflected light is transmitted to the photodetector. Specifically, the first end of the detection fiber can be set at the detection position of the near-infrared probe.

In one embodiment of the present disclosure, the first end of the detection fiber and the first end of the emission fiber are arranged on the near-infrared probe so that the distance between the first end of each emission fiber and the first end of the detection fiber is The distance is the same. That is, the distance between the emission position and the detection position corresponding to each infrared light source is the same.

Further, the setting position of the first end of the detection optical fiber on the near-infrared probe is the center of the near-infrared probe.

In one example, the positions of the first end of the detection fiber and the first end of the emission fiber on the near-infrared probe, that is, the emission position 1101 corresponding to each infrared light source and the detection position 1102 of the photodetector on the near-infrared probe , specifically as shown in Figure 11. Specifically, the emission position 1101 corresponding to the infrared light source is set around the detection position 1102 of the photodetector on the near-infrared probe, and the emission position 1101 corresponding to each infrared light source and the detection position 1102 of the photodetector on the near-infrared probe The distances are equal, and the detection position 1102 of the photodetector on the near-infrared probe is the center of the near-infrared probe.

In another embodiment of the present disclosure, the first end of the detection fiber and the first end of the emission fiber are arranged on the near-infrared probe so that each detection fiber connected to an infrared light source that emits infrared light of the same wavelength The distances between the first end and the first end of the launching optical fiber are all different. That is, the distances between the emission positions and the detection positions corresponding to infrared light sources emitting infrared light of the same wavelength are different.

Further, the first end of the detection fiber connected to the infrared light source emitting infrared light of the same wavelength may be located on the same straight line as the first end of the emission fiber.

In one example, the positions of the first end of the detection fiber and the first end of the emission fiber on the near-infrared probe, that is, the emission position 1201 corresponding to each infrared light source and the detection position 1202 of the photodetector on the near-infrared probe , as shown in Figure 12. Specifically, the distance between the emission position 1201 corresponding to each infrared light source and the detection position 1202 of the photodetector on the near-infrared probe is not equal, and the emission position 1201 corresponding to each infrared light source and the photodetector are on the near-infrared probe. The detection positions 1202 on are located on the same straight line.

Still further, the number of infrared light sources emitting infrared light of any wavelength may be at least two.

In an embodiment of the present disclosure, the nerve activity detection system 1000 may include multiple frequency-domain near-infrared detection devices 1300 , and the multiple frequency-domain near-infrared detection devices 1300 are integrated into one near-infrared detection device.

In the example shown in Figure 13, the nerve activity detection system 1000 may include two frequency-domain near-infrared detection devices 1300, and the near-infrared detection equipment is provided with launching optical fiber connection ports 1301-1, 1301-2, and detecting optical fiber Connection ports 1302-1, 1302-2. The emission fiber connection port 1301-1 is connected to the corresponding infrared light source in the first frequency-domain near-infrared detection device inside the near-infrared detection device, and the emission fiber connection port 1301-1 is connected to the corresponding first emission fiber connection port outside the near-infrared detection device. The two ends are connected; the detection fiber connection port 1302-1 is connected to the photodetector in the first frequency domain near-infrared detection device inside the near-infrared detection device, and the detection fiber connection port 1302-1 is connected to the corresponding outside of the near-infrared detection device Probe the second end connection of the fiber. The emission fiber connection port 1301-2 is connected to the corresponding infrared light source in the second frequency-domain near-infrared detection device inside the near-infrared detection device, and the emission fiber connection port 1301-2 is connected to the corresponding first end of the emission fiber outside the near-infrared detection device. The two ends are connected; the detection fiber connection port 1302-2 is connected to the photodetector in the second frequency domain near-infrared detection device inside the near-infrared detection device, and the detection fiber connection port 1302-2 is connected to the corresponding near-infrared detection device. Probe the second end connection of the fiber.

Further, the near-infrared detection device may also be provided with a USB connection port for communicating with the main control device.

In one embodiment of the present disclosure, when the main control device 1400 detects the neural activity of the subject under ultrasonic stimulation and magnetic field stimulation according to the near-infrared detection data, it is set to:

According to the near-infrared detection data corresponding to each infrared light source, the optical parameters of the object to be measured under the corresponding infrared light source are determined, wherein the optical parameters can reflect the neural activity of the object to be measured.

Optical parameters may include any one or more of amplitude, phase, and scattering coefficient.

In this embodiment, when each infrared light source emits infrared light, the light receiving module 1330 and the signal transceiver module 1310 of the frequency-domain near-infrared detection device 1300 can obtain corresponding near-infrared detection data according to the corresponding reflected light, That is, near-infrared detection data corresponding to each infrared light source is obtained.

In the embodiment in which the optical parameters include the amplitude and/or phase of the infrared light emitted by the corresponding infrared light source after being reflected by the object to be measured, according to the near-infrared detection data corresponding to any infrared light source, the position of the object to be measured under the infrared light source is determined. The optical parameters may include: performing down-sampling processing on the near-infrared detection data to obtain the second signal; performing Fourier transform on the second signal to obtain the amplitude and/or phase of the reflected light.

The amplitude in this embodiment may at least include AC amplitude. Further, the amplitude in this embodiment may include AC amplitude and DC amplitude.

The down-sampling processing is performed on the near-infrared detection data, specifically, the near-infrared data of multiple periods may be superimposed and averaged into one period of data, that is, the second signal.

Further, in an embodiment where the optical parameters include the absorption coefficient and/or scattering coefficient of the object to be measured, according to the near-infrared detection data corresponding to any infrared light source, determining the optical parameters of the object to be measured under the infrared light source may include : performing down-sampling processing on the near-infrared detection data to obtain a second signal; performing Fourier transform on the second signal to obtain an amplitude and a phase; and obtaining an absorption coefficient and/or a scattering coefficient according to the amplitude and phase.

In the embodiment where the first end of the detection fiber and the first end of the emission fiber are arranged on the near-infrared probe, so that the distance between the first end of each detection fiber and the first end of the emission fiber is the same, it can be The absorption coefficient and scattering coefficient are determined by the following formula:

D=v[3(μ _α +μ' _s )] ^-1

μ′ _s =μ _s (1-g)g=<cosθ>, 0<θ<π

Among them, μ _α is the absorption coefficient, μ′ _s is the reduced scattering coefficient, μ _s is the scattering coefficient, g is the anisotropy factor, U _DC (r) is the DC amplitude, U _Ac (r, ω) is the AC amplitude, φ(r, ω) is the phase, ω is the frequency of the AC drive signal, v is the propagation speed of the infrared light emitted by the corresponding light source, r is the distance between the first end of the detection fiber and the first end of the emission fiber, φ _s is the preset initial phase, P _DC is the DC transmission power, and P(ω) is the AC transmission power.

In this embodiment, according to the DC amplitude, AC amplitude and phase of the infrared light emitted by an infrared light source reflected by the object to be measured, the absorption coefficient and scattering coefficient of the object to be measured under the irradiation of the infrared light emitted by the infrared light source can be obtained .

The first end of the detection fiber and the first end of the emission fiber are arranged on the near-infrared probe, so that the first end of each detection fiber connected to the infrared light source that emits the same wavelength infrared light is connected to the first end of the emission fiber. In an embodiment where the distances between one ends are different, the absorption coefficient and the reduced scattering coefficient can be determined by the following slope formula:

D=v[3(μ _α +μ' _s )] ^-1

μ′ _s =μ _s (1-g)g=<cosθ>, 0<θ<π

Among them, r is the distance between the first end of the detection fiber connected to the corresponding infrared light source and the first end of the emission fiber, S _Dc is the slope relationship between the DC amplitude and the distance r, S _Ac is the AC amplitude and the distance r The slope relationship between, S _φ is the slope relationship between the phase and the distance r, ω is the frequency of the AC drive signal, v is the propagation speed of the infrared light emitted by the corresponding infrared light source, U _DC (r) is the DC amplitude, U _AC (r) is the AC amplitude, φ(r) is the phase, μ′ _s is the reduced scattering coefficient of the object to be measured under the irradiation of infrared light emitted by the corresponding infrared light source, and μ _s is the light emission of the object to be measured under the corresponding infrared light source. Scattering coefficient under infrared light irradiation, g is anisotropy factor.

In this embodiment, according to the DC amplitude, AC amplitude and phase after the infrared light of the same wavelength emitted by multiple infrared light sources is reflected by the object to be measured, that is, according to the DC amplitude, AC amplitude and phase of the reflected light of the same wavelength, it can be Obtain the absorption coefficient and scattering coefficient of the object to be measured under the irradiation of infrared light of this wavelength.

For example, the light emitting module may include m first-type infrared light sources for emitting infrared light of a first wavelength, and n second-type infrared light sources for emitting infrared light of a second wavelength. After the m first-type infrared light sources emit light sequentially, reflected light corresponding to each first-type infrared light source can be obtained. According to the reflected light corresponding to each first-type infrared light source, the near-infrared detection data corresponding to each first-type infrared light source can be obtained. According to the near-infrared detection data corresponding to each first-type infrared light source, the DC amplitude, AC amplitude and phase of the reflected light corresponding to each first-type infrared light source can be obtained. The DC amplitude, AC amplitude and phase parameter slopes of the reflected light corresponding to each first type of infrared light source are respectively fitted by the least squares method, and then substituted into the above slope formula, the object to be measured at the first wavelength can be obtained. Absorption and scattering coefficients under infrared light irradiation. After the n second-type infrared light sources emit light sequentially, reflected light corresponding to each second-type infrared light source can be obtained. According to the reflected light corresponding to each second-type infrared light source, the near-infrared detection data corresponding to each second-type infrared light source can be obtained. According to the near-infrared detection data corresponding to each second-type infrared light source, the DC amplitude, AC amplitude and phase of the reflected light corresponding to each second-type infrared light source can be obtained. The DC amplitude, AC amplitude and phase parameter slopes of the reflected light corresponding to each second type of infrared light source are respectively fitted by the least squares method, and then substituted into the above slope formula, the object to be measured at the second wavelength can be obtained. Absorption and scattering coefficients under infrared light irradiation.

Wherein, the first wavelength and the second wavelength may be pre-set according to application scenarios or specific requirements. For example, the first wavelength may be 690nm and the second wavelength may be 830nm.

In this way, when the distance between the first end of the detection optical fiber and the first end of the emission optical fiber is the same, the environmental interference of the near-infrared detection of the object to be tested can be eliminated, and the influence of artifacts caused by human motion can also be reduced.

In another embodiment of the present disclosure, the main control device 1400 is configured to:

According to the near-infrared detection data corresponding to each infrared light source, determine the optical parameters of the object to be measured under the corresponding infrared light source; according to the optical parameters of the object to be measured under each infrared light source, detect the blood oxygen data of the object to be measured, wherein, Optical parameters and blood oxygen data can reflect the neural activity of the subject to be measured.

According to the near-infrared detection data corresponding to each infrared light source, the manner of determining the optical parameters of the object to be measured under the corresponding infrared light source can refer to the foregoing embodiments, which will not be repeated here.

The first end of the detection fiber and the first end of the emission fiber are arranged on the near-infrared probe, so that the first end of each detection fiber connected to the infrared light source that emits the same wavelength infrared light is connected to the first end of the emission fiber. In the embodiment where the distances between one ends are all different, the light emitting module may include m first-type infrared light sources for emitting infrared light of the first wavelength, and n first-type infrared light sources for emitting infrared light of the second wavelength. Class II infrared light source.

According to the optical parameters of the object to be measured under each infrared light source, detecting the blood oxygen data of the object to be measured may include: according to the absorption coefficient of the object to be measured under the irradiation of infrared light of the first wavelength, The absorption coefficient under the irradiation of infrared light is used to determine the blood oxygen data of the subject to be measured.

Specifically, the blood oxygen data of the subject to be measured can be obtained by the following formula:

C _THB ＝C _HB +C _HBO

Wherein, C _HBO represents the oxygenated hemoglobin concentration of the object to be measured; _CHB represents the deoxygenated hemoglobin concentration of the object to be measured; Indicates the volume fraction of water content in the object to be tested; /> Indicates the absorption coefficient of the object to be measured under the irradiation of infrared light of the first wavelength, /> Indicates the absorption coefficient of the object to be measured under the irradiation of infrared light of the second wavelength, /> Indicates the absorption coefficient of water under the irradiation of infrared light of the first wavelength, /> Indicates the absorption coefficient of water under the irradiation of infrared light of the second wavelength, /> Indicates the molar extinction coefficient of HBO (oxyhemoglobin) under the infrared light of the first wavelength; /> Indicates the molar extinction coefficient of HB (deoxygenated hemoglobin concentration) under the infrared light of the first wavelength; /> Indicates the molar extinction coefficient of HBO (oxyhemoglobin) under the infrared light of the second wavelength; /> Represents the molar extinction coefficient of HB (deoxygenated hemoglobin concentration) under the infrared light of the second wavelength; THB represents the total hemoglobin concentration, and STO2 represents the blood oxygen saturation.

The blood oxygen data in this embodiment may include any one or more of oxyhemoglobin, deoxygenated hemoglobin concentration, total hemoglobin concentration, and blood oxygen saturation.

It should be noted that the blood oxygen concentration of the subject to be measured obtained through this embodiment is an absolute value rather than a relative value.

Through the embodiments of the present disclosure, it is detected that the blood oxygen data of the subject to be measured is absolute value data, which can reduce the relative influence of the blood oxygen data detection system itself on the near-infrared light emission and reception caused by hardware circuits. Moreover, the blood oxygen data detection system is highly integrated, small in size, and has high temporal and spatial resolution, and can realize non-invasive detection of the object to be measured (biological tissue) and accurately obtain the absolute value of the blood oxygen data. In addition, using the multi-distance solution algorithm to solve the absorption coefficient and the reduced scattering coefficient can simplify the calculation process and improve the calculation accuracy.

In an embodiment of the present disclosure, the nerve activity detection system may further include a display device for displaying parameter values of nerve parameters.

Further, the display device can also be used to display the waveform of near-infrared detection data, can also be used to display the waveform of the processed optical parameters (amplitude and phase), and can also be used to display the signal of infrared light emitted by each infrared light source Parameters and processing to obtain variations in scattering coefficients.

In an embodiment of the present disclosure, the display device and the main control device may be provided by the same host computer.

When the neural activity detection system of this embodiment detects the neural activity of the head of the human body, the magnetic pole gap of the electromagnet can be adjusted so that the magnetic pole gap is larger than the width of the body, and the human body is placed between the two magnetic poles of the electromagnet; The first ultrasonic transducer is close to the target to be stimulated on the head, and the first ultrasonic transducer is coupled with the head through an ultrasonic coupling agent; the near-infrared probe is attached to the target to be detected on the surface of the scalp to ensure that the near-infrared probe is close to the head part; the detection parameters of the magnetic field parameters, ultrasonic parameters, and light source parameters of the near-infrared device are set through the main control device. Among them, the magnetic field parameters include magnetic field strength and constant current source current direction; ultrasonic parameters include fundamental wave polarity, fundamental wave frequency F, fundamental wave amplitude, fundamental wave number, pulse period, pulse number, stimulation period and stimulation number The light source parameters of the near-infrared device include the light source modulation signal gain, and the light source modulation signal gain can be -10dB for example; the detection parameters of the near-infrared device can include the heterodyne local oscillator signal gain, ADC sampling points and pre-gain, the heterodyne local For example, the vibration signal gain can be set to -6dB, the number of ADC sampling points can be set to 1000 points, and the pre-gain setting can be set to x1, for example. When there is no magnetic-acoustic stimulation, start near-infrared detection, real-time detection and record the parameter value of the nerve parameters of the head outside the first ultrasonic transducer without magnetic-acoustic stimulation; Parameter values of nerve parameters in the outer head of the ultrasound transducer.

Replace the second ultrasonic transducer and make the stimulation target of the second ultrasonic transducer the same as that of the first ultrasonic transducer. The focal sound intensity generated by the second transducer in free water is the same as that of the first transducer in free water The focal sound intensity produced in water is the same. The magnetic field setting and near-infrared detection parameters are not changed. When there is no magnetic-acoustic stimulation, start near-infrared detection, detect and record the parameter values of the nerve parameters at the central opening of the second ultrasonic transducer in real-time without magnetic-acoustic stimulation; Parameter values of the nerve parameters of the head at the central opening of the two ultrasound transducers.

In this way, the neural activity detection of any detection point in the whole brain region under the magnetic acoustic stimulation at the same position can be realized.

On the basis of this embodiment, the near-infrared detection step may include: placing the near-infrared probe fixing device of the frequency-domain near-infrared detection device on the cerebral cortex area to be detected; turning on the power of the frequency-domain near-infrared detection device, and Open and connect the serial port of the frequency-domain near-infrared detection device on the main control device; set the relevant parameters of the frequency-domain near-infrared detection device on the main control device, including the output gain settings of the two radio frequency signals in the signal transceiver module, and the front-end of the ADC acquisition module The amplification mode and multiple setting of the first-stage amplifier. Click the start button in the main control device to write the control command into the frequency-domain near-infrared detection device, the frequency-domain near-infrared detection device performs an initialization operation, and the frequency-domain near-infrared detection device returns the corresponding status to the main control device after initialization information.

Click the start working button in the main control device, the main control device transmits the command to start working to the frequency domain near-infrared detection device, and the frequency domain near-infrared detection device starts to work. The signal transceiver module generates the first radio frequency signal and the second radio frequency signal. The optical transmitting module directly modulates the infrared light source with the first radio frequency signal, and controls multiple infrared light sources to emit light in a time-division multiplexing manner. The optical receiving module cooperates with the second radio frequency signal. The radio frequency signal performs heterodyne detection on the detected reflected light to obtain a difference frequency voltage signal, and the signal transceiver module processes the difference frequency voltage signal to obtain near-infrared detection data, and transmits the near-infrared detection data to the main control device.

The main control device processes and calculates the near-infrared detection data uploaded by the frequency-domain near-infrared detection device to obtain the parameter value of the nerve parameter. The neural parameters include amplitude and phase, and may also include scattering coefficients. According to the relationship between the emission position of the light source in the near-infrared probe and the detection position of the photodetector, the amplitude, phase and scattering coefficient corresponding to each infrared light source are imaged, so as to intuitively observe the nerves of the cortical network nodes in the detected area organize activity.

By clicking the end work button in the main control device, the main control device transmits the command to end the work to the frequency-domain near-infrared detection device, the frequency-domain near-infrared detection device stops working, and the near-infrared detection process ends.

Having described various embodiments of the present disclosure above, the foregoing description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and alterations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principle of each embodiment, practical application or technical improvement in the market, or to enable other ordinary skilled in the art to understand each embodiment disclosed herein. The scope of the present disclosure is defined by the appended claims.

Claims (10)

1. A neural activity detection system under transcranial magnetoacoustic stimulation, comprising: the device comprises a transcranial ultrasonic stimulation device, a magnetic field generating device, a frequency domain near infrared detection device and a main control device;

the transcranial ultrasonic stimulation device is arranged to send out target ultrasonic waves to an object to be tested so as to perform ultrasonic stimulation on the object to be tested;

The magnetic field generating device is arranged to generate a target magnetic field at the position of the object to be detected so as to perform magnetic field stimulation on the object to be detected;

the frequency domain near infrared detection device is arranged to perform near infrared detection on the object to be detected under the ultrasonic stimulation and the magnetic field stimulation to obtain near infrared detection data of the object to be detected;

the main control device is set to obtain a preset parameter value of a nerve parameter according to the near infrared detection data, wherein the nerve parameter is a parameter reflecting the nerve activity of the object to be tested under the ultrasonic stimulation and the magnetic field stimulation.

2. The neural activity detection system of claim 1, the frequency domain near infrared detection device comprising a signal transceiver module, a light emitting module, and a light receiving module, the light emitting module comprising at least one infrared light source, the light receiving module comprising a photodetector for receiving an optical signal;

the signal transceiver module is configured to output a first radio frequency signal of a first frequency and a control signal corresponding to each of the infrared light sources to the light emitting module, and output a second radio frequency signal of a second frequency to the light receiving module; wherein the phases of the first radio frequency signal and the second radio frequency signal are the same;

The light emitting module is arranged to sequentially emit infrared light with set wavelength through the at least one infrared light source according to the first radio frequency signal and the control signal;

the light receiving module is arranged to heterodyne the received reflected light and the second radio frequency signal to obtain a difference frequency voltage signal; the reflected light is infrared light reflected to the photoelectric detector by the object to be detected;

the signal receiving and transmitting module is further configured to process the difference frequency voltage signal to obtain the near infrared detection data.

3. The neural activity detection system of claim 2, wherein the light emitting module further comprises a radio frequency selection switch unit and a first driving unit corresponding to each of the infrared light sources,

the radio frequency selection switch unit comprises switch channels which are in one-to-one correspondence with each infrared light source, and the radio frequency selection switch unit is arranged to select the on switch channels according to the control signals so as to transmit the first radio frequency signals to the corresponding first driving units;

the first driving unit is arranged to drive the corresponding infrared light source to emit the infrared light according to the first radio frequency signal.

4. The neural activity detection system of claim 2, wherein the light receiving module includes a heterodyne detection unit and a signal processing unit,

the photoelectric detector is arranged to perform photoelectric conversion processing on the reflected light to obtain a first signal;

the heterodyne detection unit is arranged to heterodyne detect the first signal and the second radio frequency signal to obtain a difference frequency current signal;

the signal processing unit is configured to perform current-voltage conversion processing on the difference frequency current signal to obtain the difference frequency voltage signal.

5. The neural activity detection system of claim 2, wherein the signal transceiver module comprises a control unit, a first signal source unit, a second signal source unit,

the control unit is configured to control the first signal source unit to output the first radio frequency signal and control the second signal source unit to output the second radio frequency signal, and phases of the first radio frequency signal and the second radio frequency signal are the same;

the control unit is further configured to output the control signal to control the at least one infrared light source to sequentially emit light;

the signal receiving and transmitting module further comprises an analog-to-digital conversion unit, and the analog-to-digital conversion unit is arranged to perform analog-to-digital conversion processing on the difference frequency voltage signal to obtain the near infrared detection data.

6. The neural activity detection system according to claim 1, wherein the main control device is configured to, when obtaining a parameter value of a preset neural parameter according to the near infrared detection data:

determining optical parameters of the object to be detected under the corresponding infrared light sources according to the near infrared detection data corresponding to each infrared light source; or,

determining optical parameters of the object to be detected under the corresponding infrared light sources according to the near infrared detection data corresponding to each infrared light source; detecting blood oxygen data of an object to be detected according to optical parameters of the object to be detected under each infrared light source;

wherein the optical parameter and the blood oxygen data are neural parameters reflecting neural activity of the subject to be measured.

7. The neural activity detection system of claim 2, wherein the near infrared detection device further comprises a near infrared probe, a detection fiber, and an emission fiber corresponding to each of the infrared light sources,

the first end of the transmitting optical fiber is arranged on the near infrared probe, and the second end of the transmitting optical fiber is connected with a corresponding infrared light source so that infrared light emitted by the infrared light source is transmitted to the object to be detected contacted by the near infrared probe through the corresponding transmitting optical fiber;

The first end of the detection optical fiber is arranged on the near infrared probe, and the second end of the detection optical fiber is connected with the photoelectric detector so that the reflected light is transmitted to the photoelectric detector.

8. The nerve activity detection system of claim 7, wherein the first end of the detection fiber and the first end of the emission fiber are positioned on the near infrared probe such that a distance between the first end of each of the emission fibers and the first end of the detection fiber is the same.

9. The neural activity detection system of claim 1, wherein the transcranial ultrasonic stimulation device comprises an ultrasonic signal source, a power amplification module, and an ultrasonic transducer,

the ultrasonic signal source generates an ultrasonic driving signal;

the power amplification module is arranged to amplify the ultrasonic driving signal;

the ultrasonic transducer is configured to convert the amplified ultrasonic drive signal into the target ultrasonic wave.

10. The neural activity detection system of claim 1, the ultrasound transducer comprising a first ultrasound transducer and a second ultrasound transducer, a first surface of the first ultrasound transducer being circular and a second surface of the second ultrasound transducer being annular, wherein the first surface is a surface of the first ultrasound transducer for contact with the subject to be detected and the second surface is a surface of the second ultrasound transducer for contact with the subject to be detected.