CN104598575B - The brain-machine interaction image indexing system being imaged based on real-time functional magnetic resonance - Google Patents

The brain-machine interaction image indexing system being imaged based on real-time functional magnetic resonance Download PDF

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CN104598575B
CN104598575B CN201510016541.8A CN201510016541A CN104598575B CN 104598575 B CN104598575 B CN 104598575B CN 201510016541 A CN201510016541 A CN 201510016541A CN 104598575 B CN104598575 B CN 104598575B
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闫镔
李永丽
童莉
郑载舟
王林元
马丽嘉
李中林
曾颖
张驰
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PLA Information Engineering University
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Abstract

The invention discloses a kind of brain-machine interaction image indexing system being imaged based on real-time functional magnetic resonance, overcome in the prior art, the problem of brain-machine interaction image indexing system still needs to improve.The invention, which contains, to have the following steps:1st, by gathering fMRI data, training image semanteme real-time grading model, the real-time assessment models of characteristics of image similitude and vision attention real-time decoding model in advance;2nd, an image to be retrieved is presented as visual stimulus to subject, while gathering subject fMRI data, uses the semantic classes of image application processing Model checking image to be retrieved;3rd, the image and image to be retrieved that represent differentiated semantic classes result are presented to subject together, whether subject is correct by the semantic classes of vision attention feedback image semantic classification Model checking;4th, the result differentiated according to the semantic classification of subject feedback, provides the image retrieved.The present invention is significant to improving fMRI image retrieval accuracy.

Description

The brain-machine interaction image indexing system being imaged based on real-time functional magnetic resonance
Technical field
The invention is related to a kind of brain-machine interaction image indexing system, it is more particularly to a kind of based on real-time functional magnetic resonance into The brain-machine interaction image indexing system of picture.
Background technology
Functional mri(functional Magnetic Resonance Imaging)Main method be blood oxygen Horizontal dependency (BOLD, Blood Oxygenation Level Dependent) method, this method is gathered using MRI machine The information of brain, main reflection is activated in brain area capillary using voxel as the instantaneous change of unit oxygenated blood red blood cell concentration Change, abbreviation BOLD-fMRI (Blood oxygenation level dependent functional magnetic resonance imaging, BOLD-fMRI).Compared with other cerebral function imaging modes, BOLD-fMRI be imaged on speed and With with very big advantage, especially causing the relative complex brain Cognitive Function Research such as visual performance to obtain in terms of spatial resolution To carry out in a deep going way, therefore, the main flow that brain Cognitive Study has become cerebral function imaging is carried out using it.
Real-time functional magnetic resonance is imaged(rtfMRI, real-time functional Magnetic Resonance Imaging)By the way of online acquisition and processing data, make data processing suitable with data acquisition speed, can be in scanning During real-time monitoring data quality and one gather the repetition time(TR, Time of Repetition)Interior completion is simultaneously real When obtain result, the brain activity state that result reflects is fed back into subject in the way of vision or the sense of hearing, so that shape Into from subject to fMRI again to the information circuits of subject so that the brain-machine interaction based on rtfMRI is possibly realized.
Existing achievement in research, is mainly based upon fMRI image classification and identification, and these researchs are generally using offline The mode of data processing.Although these models and method can complete the assessment for image, semantic classification and characteristic similarity, But do not possess online image retrieval ability also, it is impossible to be individually formed image indexing system.
It is always the Disciplinary Frontiers and hot issue in brain science research, spy for the information decoding of human brain visual performance It is not what kind of brain response research human brain visual performance related brain areas can produce to the image seen, achieves a series of key Achievement.2001, Haxby et al. utilized the difference of the class image human brain visual performance fMRI data of multi-voxel proton analysis method research 8, Give preferable semantic classification result.2008, Kay et al. utilized Gabor wavelet pyramid simulation human brain Visual Neuron Receptive field, the image similarity assessment models based on brain signal are established, so as to realize accurately identifying for 120 width images. Naselaris in 2009 et al. proposes image similarity and semantic fusion model based on Bayes frameworks.
LaConte in 2007 constructs the rtfMRI systems of online classification that can carry out first, and the system can be using complete Brain image is trained, and On-line funchon state classification is carried out using trained listening group, and the system realizes two class mood work( The classification of energy, demonstrates the feasibility that brain-computer interface is built using cerebral function state classification method.Lee in 2009 et al. is built RtfMRI systems are classified to right-hand man to the signal of the functional areas of finger, then the control that classification results are converted into mechanical arm refers to Order, completes control of the brain-computer interface to external equipment.Andersson in 2013 et al. is by SVM classifier to visual attention Direction is classified, and the rtfMRI brain machine interface systems that tele-robotic is roamed can be manipulated by constructing.There is presently no RtfMRI brain-computer interfaces technology is applied to image retrieval by research.
The content of the invention
There is provided a kind of performance for the problem of still needing to improve instant invention overcomes brain-machine interaction image indexing system in the prior art The brain-machine interaction image indexing system being preferably imaged based on real-time functional magnetic resonance.
The present invention technical solution be to provide it is a kind of have steps of based on real-time functional magnetic resonance be imaged Brain-machine interaction image indexing system:Containing having the following steps:
Step 1, by gathering fMRI data in advance, training image semanteme real-time grading model, characteristics of image similitude are real When assessment models and vision attention real-time decoding model;
Step 2, to subject an image to be retrieved is presented as visual stimulus, while gathering subject fMRI data, uses The semantic classes of image application processing Model checking image to be retrieved;
Step 3, the image and image to be retrieved that represent differentiated semantic classes result be presented to subject together, pinged Whether the semantic classes for crossing vision attention feedback image semantic classification Model checking is correct;
Step 4, the result differentiated according to the semantic classification of subject feedback, fused images semanteme real-time grading model and image The real-time assessment models of similitude, provide the image retrieved from image library.
The step 1 is concretely comprised the following steps:Subject participates in a brain area registered placement experiment, an image, semantic point in advance Class training experiment and a vision attention classification based training experiment, gather corresponding fMRI data, are respectively trained based on supporting vector Realtime graphic semantic classification model, the vision attention real-time decoding model of machine are similar with based on the pyramidal image of Gabor wavelet Property assessment models.
The step 2 is concretely comprised the following steps:An image to be retrieved is presented as visual stimulus to subject, gathers simultaneously FMRI data, stimulus duration is 3 TR, and then stimulating image is entered using the image, semantic real-time grading model trained Row semantic classification, whole data prediction and assorting process are completed in 1 TR.
The step 3 is concretely comprised the following steps:The image and image to be retrieved of differentiated semantic classes result will be represented together Subject is presented to, image to be retrieved is placed on the left side of visual stimulus screen, and semantic classes result images are placed on visual stimulus The right side of screen;Subject differentiates whether result is correctly fed back by vision attention to semanteme, if kind judging is correct, notes Meaning sees category result image, if kind judging mistake, notes seeing image to be retrieved, vision attention interaction continues 2 TR; The visual attention information of subject then is calculated using vision attention real-time decoding model, so as to obtain semantic classes result of determination Whether correct information, data prediction and vision attention decoding process are completed in 1 TR;The result of vision decoding is next Individual TR is presented to subject by visual stimulus screen.
The step 4 is concretely comprised the following steps:Result is differentiated according to the semantic classification of subject feedback, result is correct if differentiating, Directly use the real-time assessment models of image similarity, using in image library with the width image of image similarity highest 10 to be retrieved as Retrieval result is exported in visual stimulus screen;If differentiating result mistake, the semantic real-time grading of Bayes methods fused images is used Model and the real-time assessment models of image similarity, provide 10 maximum width images of posterior probability as retrieval result in visual stimulus Exported on screen, all calculating of the process and result are shown in completion in 2 TR.
Compared with prior art, the present invention is had based on the brain-machine interaction image indexing system that real-time functional magnetic resonance is imaged Advantages below:The system innovation proposes to merge on image, semantic real-time grading model and the real-time assessment models of image similarity, And online image retrieval is realized with reference to rtfMRI technologies, real-time brain-machine interaction method is introduced into image retrieval, to improving fMRI figures As retrieval accuracy is significant.This image indexing system can be used as and utilize human brain visual information Intelligent treatment mechanism A platform, can also regard as real-time functional magnetic resonance imaging on the basis of brain-machine interaction Vision information processing example, For effect and value of the research with uniqueness of human brain Vision information processing mechanism.
Brief description of the drawings
Fig. 1 is the schematic flow sheet for the brain-machine interaction image indexing system that the present invention is imaged based on real-time functional magnetic resonance.
Embodiment
The brain-machine interaction figure being imaged with reference to the accompanying drawings and detailed description to the present invention based on real-time functional magnetic resonance As searching system is described further:
As illustrated, the present embodiment is broadly divided into model training, semantic classes judges, the interaction of classification judged result and retrieval As a result four functional modules are exported.The system is by the preparation function of first online image retrieval of Implement of Function Module, mainly Including collection fMRI data in advance, training image semanteme real-time grading model, the real-time assessment models of image similarity and vision note Meaning real-time decoding model;Then online retrieving is realized by rear three modules, including:It is in subject by second module An existing image to be retrieved is as visual stimulus, while subject fMRI data are gathered, first using image application processing Model checking The semantic classes of image to be retrieved;Then the image of differentiated semantic classes result will be represented and to be retrieved by the 3rd module Image is presented to subject together, and whether just subject passes through the semantic classes of vision attention feedback image semantic classification Model checking Really;The result differentiated finally by the 4th module according to the semantic classification of subject feedback, fused images semanteme real-time grading mould Type and the real-time assessment models of image similarity, provide the image that image indexing system is retrieved.
Comprise the following steps that, step 1:By gathering fMRI data, training image semanteme real-time grading model, image in advance The real-time assessment models of similitude and vision attention real-time decoding model, specific method is:Subject participates in a brain area registration in advance Positioning experiment, an image application processing training experiment and a vision attention classification based training experiment, gather corresponding fMRI numbers According to the realtime graphic semantic classification model based on SVMs, vision attention real-time decoding model is respectively trained and is based on The pyramidal image similarity assessment model of Gabor wavelet.
Step 2:An image to be retrieved is presented as visual stimulus to subject, while gathering subject fMRI data, uses The semantic classes of image, semantic real-time grading Model checking image to be retrieved, specific method is:It is to be retrieved to subject presentation one Image is as visual stimulus, while gathering fMRI data, stimulus duration is 3 TR(6s).Then utilize the figure trained The semantic real-time grading model of picture carries out semantic classification to stimulating image, and whole data prediction and assorting process are complete in 1 TR Into.
Step 3:The image and image to be retrieved that represent differentiated semantic classes result are presented to subject together, pinged Whether the semantic classes for crossing the semantic real-time grading Model checking of vision attention feedback image is correct, and specific method is:Institute will be represented Differentiate that the image and image to be retrieved of semantic classes result are presented to subject together, image to be retrieved is placed on visual stimulus screen Left side, semantic classes result images are placed on the right side of visual stimulus screen.Subject is differentiated by vision attention to semanteme to be tied Whether fruit is correctly fed back, if kind judging is correct, notes seeing category result image, if kind judging mistake, notes See image to be retrieved.Vision attention interaction continues 2 TR.Then subject is calculated using vision attention real-time decoding model Visual attention information, so as to obtain the whether correct information of semantic classes result of determination, data prediction and vision attention solution Code process is completed in 1 TR.The result of vision decoding is presented to subject in next TR by visual stimulus screen.
Step 4:The result differentiated according to the semantic classification of subject feedback, fused images semanteme real-time grading model and image The real-time assessment models of similitude, provide the image that image indexing system is retrieved, and specific method is:According to the semanteme of subject feedback Discriminant classification result, if differentiating, result is correct, directly the use real-time assessment models of image similarity, by image library with it is to be retrieved The width image of image similarity highest 10 is exported as retrieval result in visual stimulus screen;If differentiating result mistake, use Bayes methods fused images semanteme real-time grading model and the real-time assessment models of image similarity, provide posterior probability maximum 10 width images are exported as retrieval result in visual stimulus screen, the process it is all calculating and result be shown in it is complete in 2 TR Into.

Claims (5)

1. a kind of brain-machine interaction image indexing system being imaged based on real-time functional magnetic resonance, it is characterised in that:Contain following step Suddenly:
Step 1, by gathering fMRI data in advance, training image semanteme real-time grading model, characteristics of image similitude are commented in real time Estimate model and vision attention real-time decoding model;
Step 2, to subject an image to be retrieved is presented as visual stimulus, while gathering subject fMRI data, uses image The semantic classes of semantic classification Model checking image to be retrieved;
Step 3, the image and image to be retrieved that represent differentiated semantic classes result be presented to subject together, subject is by regarding Feel and notice whether the semantic classes of feedback image semantic classification Model checking is correct;
Step 4, the result differentiated according to the semantic classification of subject feedback, fused images semanteme real-time grading model are similar with image The real-time assessment models of property, provide the image retrieved from image library.
2. the brain-machine interaction image indexing system according to claim 1 being imaged based on real-time functional magnetic resonance, its feature It is:The step 1 is concretely comprised the following steps:Subject participates in a brain area registered placement experiment, an image application processing in advance Training experiment and a vision attention classification based training experiment, gather corresponding fMRI data, are respectively trained based on SVMs Realtime graphic semantic classification model, vision attention real-time decoding model and based on the pyramidal image similarity of Gabor wavelet Assessment models.
3. the brain-machine interaction image indexing system according to claim 1 being imaged based on real-time functional magnetic resonance, its feature It is:The step 2 is concretely comprised the following steps:An image to be retrieved is presented as visual stimulus to subject, while gathering fMRI Data, stimulus duration is 3 TR, then carries out language to stimulating image using the image, semantic real-time grading model trained Justice classification, whole data prediction and assorting process are completed in 1 TR.
4. the brain-machine interaction image indexing system according to claim 1 being imaged based on real-time functional magnetic resonance, its feature It is:The step 3 is concretely comprised the following steps:The image and image to be retrieved that represent differentiated semantic classes result are presented together To subject, image to be retrieved is placed on the left side of visual stimulus screen, and semantic classes result images are placed on visual stimulus screen Right side;Subject differentiates whether result is correctly fed back by vision attention to semanteme, if kind judging is correct, notes seeing Category result image, if kind judging mistake, notes seeing image to be retrieved, vision attention interaction continues 2 TR;Then The visual attention information of subject is calculated using vision attention real-time decoding model, so as to whether obtain semantic classes result of determination Correct information, data prediction and vision attention decoding process are completed in 1 TR;The result of vision decoding is in next TR Subject is presented to by visual stimulus screen.
5. the brain-machine interaction image indexing system according to claim 1 being imaged based on real-time functional magnetic resonance, its feature It is:The step 4 is concretely comprised the following steps:Result is differentiated according to the semantic classification of subject feedback, result is correct if differentiating, directly Using the real-time assessment models of image similarity, retrieval will be used as with the width image of image similarity highest 10 to be retrieved in image library As a result exported in visual stimulus screen;If differentiating result mistake, the semantic real-time grading model of Bayes methods fused images is used With the real-time assessment models of image similarity, 10 maximum width images of posterior probability are provided as retrieval result in visual stimulus screen Upper output, all calculating of the process and result are shown in completion in 2 TR.
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