Olfactory function fMRI real-time neural feedback brain region activation monitoring system and method

Abstract

The invention discloses an olfactory function fMRI real-time nerve feedback brain region activation monitoring system and method, which can monitor the activation intensity of an olfactory brain region in real time, realize quality control of the olfactory task state fMRI olfactory brain region activation intensity, ensure that olfactory function imaging examination is accurate and reliable, realize individualized olfactory activated brain region positioning and improve the olfactory function imaging examination accuracy. According to the method, accurate target brain region information can be provided for a testee, the testee and an experimenter are guided to collect effective olfactory task state fMRI data, and the method is of great significance to research of olfactory related cognitive neurodegenerative diseases. The system comprises a scale and olfactory behavior data acquisition module, an individualized primary olfactory cortex target module, a dynamic multi-stage olfactory fMRI module, a real-time olfactory activation target region activation intensity monitoring module and an olfactory task state fMRI effect evaluation module.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical image processing, and in particular relates to an olfactory function fMRI real-time neural feedback brain region activation monitoring system and a working method of the olfactory function fMRI real-time neural feedback brain region activation monitoring system. Background Art

[0002] In the field of cognitive neuroscience, symptoms of olfactory impairment can appear in a variety of neurological diseases, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, Huntington's disease, motor neuron disease, etc. Therefore, timely assessment of central olfactory function is of great value for the early diagnosis of neurological diseases.

[0003] Functional magnetic resonance imaging (fMRI) is a currently available, noninvasive imaging method for studying human central olfactory function, providing valuable insights into medicine, physiology, psychology, and even cognitive science. Studies have shown that olfactory function is significantly correlated with cognition, and early cognitive decline is often accompanied by olfactory impairment. Therefore, fMRI activation of olfactory-related brain regions is an objective and effective biomarker for the early assessment of cognitive impairment. Studies have shown that fMRI based on odor identification tasks can detect activation in the olfactory bulb-olfactory tract-entorhinal cortex-hippocampus-orbitofrontal cortex neural circuit. Therefore, fMRI based on odor identification tasks can detect abnormalities in the olfactory circuitry associated with neurodegenerative diseases, facilitating the understanding of the central mechanisms underlying olfactory impairment. Furthermore, olfactory impairment also occurs during normal aging, and olfactory impairment lacks specificity for the early diagnosis of various neurological diseases. Therefore, there is a need for a highly sensitive and specific MRI-compatible method for detecting olfactory cortex activation.

[0004] The main difficulties with olfactory functional fMRI lie in the methods and equipment used for olfactory functional imaging. Current olfactory fMRI examinations in China are relatively simple in design, and there are no specific rules for administering and timing olfactory stimulation. When people are continuously exposed to an odor in an environment, the olfactory neurons respond to the odor and depolarize. G-protein-mediated second messengers activate adenylate cyclase, increasing intracellular cyclic adenosine monophosphate concentrations and subsequently opening cyclic nucleotide-gated ion channels. Next, a rapid influx of calcium ions triggers a chemical cascade that triggers olfactory fatigue, causing cyclic nucleotide-gated ion channels to close and preventing similar odor molecules from activating receptors and sending electrical signals to the brain for olfactory perception. Repeated exposure to the same concentration of olfactory stimulation can produce olfactory fatigue, which can bias MRI findings of olfactory cortex activation.

[0005] However, currently, task-based olfactory fMRI data acquisition requires offline processing after the subject completes all tasks to generate activation maps of the olfactory brain region. However, if the subject fails to cooperate during the task, the experimenter cannot promptly assess the quality of the task-based fMRI data. This can result in suboptimal activation of the subject's primary olfactory cortex, making subsequent data analysis unusable. Excluding the subject or recalling them for re-analysis will affect the progress of the experiment. Therefore, the deployment of a real-time activation monitoring system for task-based fMRI is crucial for ensuring the quality of fMRI data acquisition. Summary of the Invention

[0006] In order to overcome the shortcomings of the existing technology, the technical problem to be solved by the present invention is to provide an olfactory function fMRI real-time neural feedback brain area activation monitoring system, which can monitor the activation intensity of the olfactory brain area in real time, realize the quality control of the olfactory brain area activation intensity of the olfactory task-state fMRI, ensure the accuracy and reliability of olfactory functional imaging examinations, realize individualized olfactory activation brain area positioning, and can provide subjects with relatively accurate target brain area information, guiding subjects and experimenters to collect effective olfactory task-state fMRI data, which is of great significance for the study of olfactory-related cognitive neurodegenerative diseases.

[0007] The technical solution of the present invention is: this olfactory function fMRI real-time neurofeedback brain area activation monitoring system comprises:

[0008] The scale and olfactory behavioral data collection module is configured to perform cognitive behavioral scales, randomly divide the screened subjects into experimental and control groups matched in age and number, and evaluate the subjects' olfactory behavioral functions through computerized olfactory threshold and olfactory identification tests;

[0009] The personalized primary olfactory cortex target module is configured to obtain a nonlinear transformation matrix from the individual space to the standard space using the subject's brain structural MRI modality data. Then, through the inverse transformation of the matrix, the region of interest of the primary olfactory cortex in the standard space is projected into the subject's individual space, obtaining the subject's personalized primary olfactory cortex brain region as a monitoring target for subsequent neurofeedback.

[0010] The dynamic multi-stage olfactory fMRI module is configured to activate the primary olfactory cortex using an olfactory-visual correlation fMRI paradigm. The olfactory-visual correlation fMRI paradigm includes: alternating odor and visual, and visual-only stimulation conditions; in the alternating odor and visual stimulation condition, a visual cue for smelling appears on the screen while the specific odor is delivered to the subject through a tube; in the visual-only stimulation condition, a visual cue for smelling appears on the screen while unscented air is delivered to the subject; the specific odor and unscented air are delivered using an MRI-compatible olfactometer; the specific odor is delivered using the same odor at increasing concentrations;

[0011] A real-time olfactory activation target area activation intensity monitoring module is configured to collect experimental data through magnetic resonance imaging. The percentage change in the time series signal of the primary olfactory cortex brain area obtained by the individualized primary olfactory cortex target module is used as a neural feedback signal. The signal is fed back to the subject using a visual neural feedback stimulation image. When the percentage change in the signal is less than a minimum threshold, the height of the image remains unchanged. When the percentage change in the signal is greater than the threshold, the height of the image increases.

[0012] The olfactory task-state fMRI effect evaluation module is configured to evaluate the correlation between the task-state olfactory fMRI data collected by the system and the scale and olfactory behavior, and the correlation between the olfactory fMRI data obtained by offline collection and the scale and olfactory behavior.

[0013] The present invention can monitor the activation intensity of the olfactory brain area in real time, achieve quality control of the activation intensity of the olfactory brain area in the olfactory task-state fMRI, ensure the accuracy and reliability of olfactory functional imaging examinations, realize individualized olfactory activation brain area positioning, provide subjects with relatively accurate target brain area information, and guide subjects and experimenters to collect effective olfactory task-state fMRI data, which is of great significance for the study of olfactory-related cognitive neurodegenerative diseases.

[0014] A method for real-time neurofeedback brain region activation monitoring using fMRI of olfactory function is also provided, comprising the following steps:

[0015] (1) Administer a cognitive behavioral scale and randomly divide the screened subjects into an experimental group and a control group matched in age and number. Use computerized olfactory threshold and olfactory identification tests to assess the subjects' olfactory behavioral function.

[0016] (2) Using the subjects' brain structural MRI modal data, we obtain a nonlinear transformation matrix from the individual space to the standard space. Then, through the inverse transformation of the matrix, we project the region of interest of the primary olfactory cortex in the standard space to the subject's individual space, obtaining the subject's individualized primary olfactory cortex brain area as the monitoring target for subsequent neurofeedback.

[0017] (3) Activate the primary olfactory cortex using an olfactory-visual association fMRI paradigm, which includes alternating odor and visual stimulation conditions and visual-only stimulation conditions;

[0018] In the alternating odor and visual stimulation condition, a visual cue to smell the odor appeared on the screen while the specific odor was delivered to the subject through a tube. In the visual-only stimulation condition, a visual cue to smell the odor appeared on the screen while unscented air was delivered to the subject. The specific odor and unscented air were delivered using an MRI-compatible olfactometer. The specific odor was the same odor at a concentration ranging from low to high.

[0019] (4) Experimental data were collected through magnetic resonance imaging, and the percentage change of the time series signal of the primary olfactory cortex brain area obtained by the individualized primary olfactory cortex target module was used as

[0020] The neurofeedback signal is fed back to the subject using an image of a neurofeedback stimulus. When the percentage change in the signal is less than the minimum threshold, the height of the image remains unchanged. When the percentage change in the signal is greater than the threshold, the height of the image increases.

[0021] (5) Evaluate the correlation between the task-based olfactory fMRI data collected using this system and the scale and olfactory behavior, and the correlation between the olfactory fMRI data obtained by offline collection and the scale and olfactory behavior. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram showing the working principle of the olfactory function fMRI real-time neurofeedback brain area activation monitoring system according to the present invention is shown.

[0023] Figure 2 A schematic structural diagram of a dynamic multi-level olfactory fMRI module according to the present invention is shown.

[0024] Figure 3 An olfactory-visual correlation fMRI paradigm according to the present invention is shown. DETAILED DESCRIPTION

[0025] like Figure 1 As shown in the figure, this olfactory functional fMRI real-time neurofeedback brain area activation monitoring system includes:

[0026] The scale and olfactory behavioral data collection module is configured to perform cognitive behavioral scales, randomly divide the screened subjects into experimental and control groups matched in age and number, and evaluate the subjects' olfactory behavioral functions through computerized olfactory threshold and olfactory identification tests;

[0027] Individualized primary olfactory cortex target modules, configured according to the subject's brain structure

[0028] MRI modality data is used to obtain a nonlinear transformation matrix from individual space to standard space. Then, through the inverse transformation of the matrix, the region of interest of the primary olfactory cortex in the standard space is projected into the subject's individual space, obtaining the subject's individualized primary olfactory cortex brain area as a monitoring target for subsequent neurofeedback.

[0029] A dynamic multi-stage olfactory fMRI module configured to activate the primary olfactory cortex using an olfactory-visual correlation fMRI paradigm, which includes alternating odor and visual, and visual-only stimulation conditions. During these alternating odor and visual stimulation conditions, a visual cue to smell an odor appears on the screen while a specific odor is delivered to the subject through a tube.

[0030] In the visual-only stimulation condition, a visual cue of smelling an odor appeared on the screen, and unscented air was delivered to the subjects. An MRI-compatible olfactometer was used to deliver both specific odors and unscented air. The specific odors used the same odor from low to high concentrations.

[0031] A real-time olfactory activation target area activation intensity monitoring module is configured to collect experimental data through magnetic resonance imaging. The percentage change in the time series signal of the primary olfactory cortex brain area obtained by the individualized primary olfactory cortex target module is used as a neural feedback signal. The signal is fed back to the subject using a visual neural feedback stimulation image. When the percentage change in the signal is less than a minimum threshold, the height of the image remains unchanged. When the percentage change in the signal is greater than the threshold, the height of the image increases.

[0032] The olfactory task-state fMRI effect evaluation module is configured to evaluate the correlation between the task-state olfactory fMRI data collected by the system and the scale and olfactory behavior, and the correlation between the olfactory fMRI data obtained by offline collection and the scale and olfactory behavior.

[0033] The present invention can monitor the activation intensity of the olfactory brain area in real time, achieve quality control of the activation intensity of the olfactory brain area in the olfactory task-state fMRI, ensure the accuracy and reliability of olfactory functional imaging examinations, realize individualized olfactory activation brain area positioning, provide subjects with relatively accurate target brain area information, and guide subjects and experimenters to collect effective olfactory task-state fMRI data, which is of great significance for the study of olfactory-related cognitive neurodegenerative diseases.

[0034] Preferably, in the scale and olfactory behavior data acquisition module,

[0035] The scale assessment includes: ① global cognitive function: Mini-Mental State Examination, Montreal Cognitive Assessment; ② episodic memory: Auditory Vocabulary Learning Test immediate, short-term, long-term, cued, and recognition memory; ③ visuospatial memory: Rey-Osterrieth complex figure recall; ④ executive function: Line-Joining Test A, Line-Joining Test B; ⑤ language function: animal word fluency, Boston naming; ⑥ visuospatial function: ROCF copying, clock drawing test; ⑦ processing speed: symbol-digit conversion test; ⑧ anxiety state: Hamilton Anxiety Rating Scale; ⑨ depression state: Hamilton Depression Rating Scale, Geriatric Depression Scale;

[0036] The olfactory behavioral test assesses the subject's ability to detect odors through an odor threshold test, and assesses the subject's ability to identify and remember odors through an odor identification and memory test. A score of 8-10 on the odor threshold test indicates normal sense of smell, and a score of 1-3 indicates olfactory dysfunction or anosmia. A score of 8 or above indicates that the olfactory threshold is within the normal range. The odor identification test assesses the ability to identify and remember odors. First, 10 odors are presented to the subject in sequence, and the subject is asked to select the odor from the screen. After an interval of 10 minutes, 20 odors are presented to the subject in sequence, 10 of which are new odors and 10 are old odors from the previous round. The subject is asked to identify each odor from 4 candidate items and answer whether he or she has smelled the odor in the previous round. The correct number is greater than 16, which is within the normal range.

[0037] Preferably, in the individualized primary olfactory cortex target module,

[0038] The DICOM format was converted into NIFTI format using the brain structure MRI modality data of the subjects. The fnirt command of fsl software was used to nonlinearly transform the brain structure data in the individual space into the MNI standard space. The transformation matrix from the individual space to the standard space was obtained.

[0039] The inwarp command projects the region of interest of the primary olfactory cortex in the standard space into the subject's individual space to obtain the subject's individualized primary olfactory cortex brain area, which serves as the monitoring target for subsequent neurofeedback.

[0040] Preferably, if Figure 2 As shown, in the dynamic multi-level olfactory fMRI module,

[0041] Lavender odor was administered at concentrations of 0.032%, 0.10%, 0.32%, and 1.0% in 1,2-propanediol as solvent. Each concentration was presented three times before increasing to the next intensity, with a rest period of 12 seconds, a visual cue only for 6 seconds, a rest period of 12 seconds, and a visual cue and odor stimulus for 6 seconds.

[0042] Seconds (such as Figure 3Each concentration was repeated three times, for a total of 108 seconds; a total of four odor concentrations were used for continuous olfactory stimulation and fMRI detection, for a total of 432 seconds; there were 12 seconds and 36 seconds of adaptation time before and after the start of the test, respectively, for a total test time of 480 seconds.

[0043] Preferably, in the real-time olfactory activation target area activation intensity monitoring module,

[0044] The height of the image rise changes with the activity of the target brain area. The neural feedback signal is updated every 2 seconds. The experimenter judges whether the olfactory brain area is activated by the change in the height of the image rise.

[0045] Preferably, in the real-time olfactory activation target area activation intensity monitoring module, if the signal intensity of the target area neural feedback signal is weak, the test is adjusted or restarted to ensure reliable olfactory task-state fMRI data acquisition.

[0046] Preferably, the olfactory task-state fMRI effect evaluation module includes a behavioral evaluation submodule and a brain imaging evaluation submodule.

[0047] The behavioral assessment submodule compares the correlation between the data of the subjects obtained by this system and offline acquisition methods and the fMRI data of the olfactory task state;

[0048] The brain imaging assessment submodule evaluates whether there is a significant difference in the intensity of olfactory activation between using this system and conventional data collection.

[0049] Preferably, in the brain imaging evaluation submodule, based on the olfactory-visual correlation fMRI paradigm, bilateral POC and bilateral hippocampus are selected as regions of interest, and the time series of the regions of interest of each subject are extracted; the connection, connection direction, and whether each brain region is directly affected by external stimuli are determined; the parameter values ​​θ and λ of the first brain region are set as the prior mean, and the EM algorithm is used to infer the variance and mean of the posterior distribution of the parameters θ and λ of the next brain region until the parameters of all brain regions are calculated; significance test: the variance and mean of the brain region connection change matrix Bj are estimated, and Laplace approximation is performed to obtain the posterior distribution. Given a threshold α, it is determined whether α falls in the rejection region of the posterior distribution, and the Bayes factor of the model is calculated to compare which model is better.

[0050] Preferably, in the brain imaging assessment submodule, a dynamic causal model (DCM) is used to analyze the directed connections of fMRI, which includes the following steps:

[0051] (I) Extract the time series of the POC, hippocampus, and OFC brain regions defined in advance for each subject;

[0052] (II) determine the connections and directions of connections, and whether each brain region is directly affected by external stimuli;

[0053] (III) setting the parameter values ​​θ and λ of the first brain region in the model to the prior mean;

[0054] (IV) using the expectation maximization algorithm to estimate the variance and mean of the posterior distribution of the parameters θ and λ of the next brain region until the parameters of all brain regions are calculated;

[0055] (V) Significance test: Estimate the variance and mean of the brain area connectivity change matrix Bj, perform Laplace approximation, and obtain the posterior distribution. Given a threshold value such as α, directly check whether α falls within the rejection region of the posterior distribution.

[0056] (VI) Validate different models and select the better model by calculating the Bayes factor of the model.

[0057] A method for real-time neurofeedback brain region activation monitoring using fMRI of olfactory function is also provided, comprising the following steps:

[0058] (1) Administer a cognitive behavioral scale and randomly divide the screened subjects into an experimental group and a control group matched in age and number. Use computerized olfactory threshold and olfactory identification tests to assess the subjects' olfactory behavioral function.

[0059] (2) Using the subjects' brain structural MRI modal data, we obtain a nonlinear transformation matrix from the individual space to the standard space. Then, through the inverse transformation of the matrix, we project the region of interest of the primary olfactory cortex in the standard space to the subject's individual space, obtaining the subject's individualized primary olfactory cortex brain area as the monitoring target for subsequent neurofeedback.

[0060] (3) Activate the primary olfactory cortex using an olfactory-visual association fMRI paradigm, which includes alternating odor and visual stimulation conditions and visual-only stimulation conditions;

[0061] In the alternating odor and visual stimulation condition, a visual cue to smell the odor appeared on the screen while the specific odor was delivered to the subject through a tube. In the visual-only stimulation condition, a visual cue to smell the odor appeared on the screen while unscented air was delivered to the subject. The specific odor and unscented air were delivered using an MRI-compatible olfactometer. The specific odor was the same odor at a concentration ranging from low to high.

[0062] (4) Experimental data were collected through magnetic resonance imaging, and the percentage change of the time series signal of the primary olfactory cortex brain area obtained by the individualized primary olfactory cortex target module was used as

[0063] The neurofeedback signal is fed back to the subject using an image of a neurofeedback stimulus. When the percentage change in the signal is less than the minimum threshold, the height of the image remains unchanged. When the percentage change in the signal is greater than the threshold, the height of the image increases.

[0064] (5) Evaluate the correlation between the task-based olfactory fMRI data collected using this system and the scale and olfactory behavior, and the correlation between the olfactory fMRI data obtained by offline collection and the scale and olfactory behavior.

[0065] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. Olfactory functional fMRI real-time neurofeedback brain activation monitoring system, characterized by: It includes: The scale and olfactory behavioral data collection module is configured to perform cognitive behavioral scales, randomly divide the screened subjects into experimental and control groups matched in age and number, and evaluate the olfactory behavioral function of the subjects through computerized olfactory threshold and olfactory identification tests; Individualized primary olfactory cortex target module, which is configured to obtain the nonlinear transformation matrix from individual space to standard space through the subject's brain structural MRI modality data, and then project the area of ​​interest of the primary olfactory cortex in the standard space to the subject's individual space through the inverse transformation of the matrix, and obtain the subject's individualized primary olfactory cortex brain area as the monitoring target for subsequent neurofeedback; Dynamic multi-stage olfactory fMRI module, configured to activate the primary olfactory cortex using an olfactory-visual association fMRI paradigm, which includes: alternating odor and visual, and visual-only stimulation conditions; in alternating odor and visual stimulation conditions, a visual cue to smell the odor appears on the screen, and the specific odor is delivered to the subject through a tube; in visual-only stimulation conditions, a visual cue to smell the odor appears on the screen, and unscented air is delivered to the subject; the specific odor and unscented air are delivered using an MRI-compatible olfactometer; the specific odor uses the same odor from low to high concentrations; The real-time olfactory activation target activation intensity monitoring module is configured to collect experimental data through magnetic resonance imaging, and the percentage change of the time series signal of the primary olfactory cortex brain area obtained by the individualized primary olfactory cortex target module is used as a neural feedback signal, and is fed back to the experimenter in the form of a vivid neural feedback stimulation image. When the percentage change of the signal is less than the minimum threshold, the height of the image remains unchanged, and when the percentage change of the signal is greater than the threshold, the height of the image increases; The olfactory task-state fMRI effect evaluation module is configured to evaluate the correlation between the task-state olfactory fMRI data collected by the system and the scale and olfactory behavior, and the correlation between the olfactory fMRI data obtained by offline collection and the scale and olfactory behavior.

2. The olfactory function fMRI real-time neurofeedback brain area activation monitoring system according to claim 1, characterized in that: In the scale and olfactory behavior data collection module, the scale assessment includes: ① overall cognitive function: brief mental state examination, Montreal cognitive assessment; ② episodic memory: auditory vocabulary learning test immediate, short-term, long-term, cue, recognition memory; ③ visual spatial memory: Rey-Osterrieth complex figure recall; ④ executive function: line drawing test A, line drawing test B; ⑤ language function: animal word fluency, Boston naming; ⑥ visual spatial function: ROCF copying, clock drawing test; ⑦ processing speed: symbol-digit conversion test; ⑧ anxiety state: Hamilton anxiety scale; ⑨ depression state: Hamilton depression scale, geriatric depression scale; The olfactory behavioral test evaluates the subject's ability to detect odors through an odor threshold test, and evaluates the subject's ability to identify and remember odors through an odor identification and memory test. A score of 8-10 in the odor threshold test indicates normal sense of smell, and a score of 1-3 indicates olfactory dysfunction or anosmia. A score of 8 or above indicates that the olfactory threshold is within the normal range. The odor identification test evaluates the ability to identify and remember odors. First, 10 odors are shown to the subject in sequence, and the subject is asked to choose the odor from the screen. After an interval of 10 minutes, 20 odors are shown to the subject in sequence, 10 of which are new odors and 10 are old odors from the previous round. The subject is asked to identify each odor from 4 candidate items and answer whether he has smelled the odor in the previous round. The correct number of answers greater than 16 is within the normal range.

3. The olfactory function fMRI real-time neurofeedback brain area activation monitoring system according to claim 2, characterized in that: In the individualized primary olfactory cortex target module, the DICOM format is converted into the NIFTI format through the brain structure MRI modality data of the subject, the fnirt command of the fsl software is used to nonlinearly transform the brain structure data in the individual space into the MNI standard space, and the transformation matrix from the individual space to the standard space is obtained. The inwarp command is used to project the region of interest of the primary olfactory cortex in the standard space into the subject's individual space, and the subject's individualized primary olfactory cortex brain area is obtained as a monitoring target for subsequent neurofeedback.

4. The olfactory function fMRI real-time neural feedback brain area activation monitoring system according to claim 3, characterized in that: In the dynamic multi-level olfactory fMRI module, Lavender odor was used at concentrations of 0.032%, 0.10%, 0.32%, and 1.0% in the solvent 1,2-propanediol, and each concentration of odor was presented three times before increasing to the next intensity, with a rest period of 12 seconds, a visual cue only for 6 seconds, a rest period of 12 seconds, and a visual cue and odor stimulation for 6 seconds.

5. The olfactory function fMRI real-time neural feedback brain area activation monitoring system according to claim 4, characterized in that: In the real-time olfactory activation target area activation intensity monitoring module, the rising height of the image changes with the activity of the target brain area, and the neural feedback signal is updated every 2 seconds. The experimenter determines whether the olfactory brain area is activated by the change in the rising height of the image.

6. The olfactory function fMRI real-time neural feedback brain area activation monitoring system according to claim 5, characterized in that: In the real-time olfactory activation target area activation intensity monitoring module, if the signal intensity of the target area neural feedback signal is weak, the test is adjusted or restarted to ensure reliable olfactory task-state fMRI data acquisition.

7. The olfactory function fMRI real-time neurofeedback brain region activation monitoring system according to claim 6, characterized in that: The olfactory task-state fMRI effect evaluation module includes a behavioral evaluation submodule and a brain imaging evaluation submodule. The behavioral assessment submodule compares the correlation between the data of the subjects obtained by the system and offline acquisition methods and the fMRI of the olfactory task state; The brain imaging assessment submodule evaluates whether there is a significant difference in the intensity of olfactory activation between using this system and conventional data collection.

8. The olfactory function fMRI real-time neurofeedback brain area activation monitoring system according to claim 7, characterized in that: In the brain image evaluation submodule, based on the olfactory-visual association fMRI paradigm, bilateral POC and bilateral hippocampus are selected as regions of interest, and the time series of the regions of interest of each subject are extracted; the connection, connection direction, and whether each brain region is directly affected by external stimuli are determined; the parameter values ​​θ and λ of the first brain region are set as the prior mean, and the EM algorithm is used to infer the variance and mean of the posterior distribution of the parameters θ and λ of the next brain region until the parameters of all brain regions are calculated; significance test: the variance and mean of the brain region connection change matrix Bj are estimated, and Laplace approximation is performed to obtain the posterior distribution. Given a threshold α, it is determined whether α falls in the rejection region of the posterior distribution, and the Bayes factor of the model is calculated to compare which model is better.

9. The olfactory function fMRI real-time neurofeedback brain area activation monitoring system according to claim 7, characterized in that: In the brain imaging assessment submodule, a dynamic causal model DCM is used to analyze the directed connections of fMRI, which includes the following steps: (I) Through the pre-defined POC, hippocampus, and OFC brain regions, the time series of the above brain regions were extracted for each subject; (II) determine the connections and directions of connections, and whether each brain area is directly affected by external stimuli; (III) setting the parameter values ​​θ and λ of the first brain region in the model to the prior mean; (IV) using the expectation maximization algorithm to estimate the variance and mean of the posterior distribution of the parameters θ and λ of the next brain region until the parameters of all brain regions are calculated; (V) Significance test: Estimate the variance and mean of the brain area connection change matrix Bj, perform Laplace approximation, and obtain the posterior distribution. Given a certain threshold such as α, directly check whether α falls in the rejection region of the posterior distribution; (VI) Verify different models and select the better model by calculating the Bayes factor of the model.

10. Olfactory functional fMRI real-time neurofeedback brain region activation monitoring method, characterized by: It includes the following steps: (1) Administer a cognitive behavioral scale and randomly divide the screened subjects into an experimental group and a control group matched in age and number. Use computerized olfactory threshold and olfactory identification tests to assess the olfactory behavioral function of the subjects. (2) Using the subjects’ brain structural MRI modality data, we obtain the nonlinear transformation matrix from the individual space to the standard space. Then, through the inverse transformation of the matrix, we project the region of interest of the primary olfactory cortex in the standard space to the subject’s individual space, and obtain the subject’s individualized primary olfactory cortex brain region as the monitoring target for subsequent neurofeedback. (3) The olfactory-visual association fMRI paradigm was used to activate the primary olfactory cortex. The olfactory-visual association fMRI paradigm included: alternating odor and visual stimulation conditions and visual-only stimulation conditions; in the alternating odor and visual stimulation conditions, a visual cue to smell the odor appeared on the screen and a specific odor was delivered to the subject through a tube; in the visual-only stimulation condition, a visual cue to smell the odor appeared on the screen and odorless air was delivered to the subject; an MRI-compatible olfactometer was used to deliver specific odors and odorless air; Specific odors use the same odor from low to high concentrations; (4) Experimental data were collected through magnetic resonance imaging, and the percentage change of the time series signal of the primary olfactory cortex brain area obtained by the individualized primary olfactory cortex target module was used as a neural feedback signal, and fed back to the experimenter in the form of a vivid neural feedback stimulation image. When the percentage change of the signal was less than the minimum threshold, the height of the image remained unchanged, and when the percentage change of the signal was greater than the threshold, the height of the image increased; (5) Evaluate the correlation between the task-based olfactory fMRI data collected by the system and the scale and olfactory behavior, and the correlation between the olfactory fMRI data obtained by offline collection and the scale and olfactory behavior.

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