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Theoretical analysis of transcranial Hall-effect stimulation based on passive cable model

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Chinese Physics B 2015年第12期24卷 373-378页

作者：袁毅李小俚 Institute of Electrical Engineering Yanshan University state key Laboratory of {2. neuroscience and learning & IDG Mc Govern Institute for Brain Research Beijing Normal University Center for Collaboration and Innovation in Brain and learning Sciences Beijing Normal University

Transcranial Hall-effect stimulation（THS） is a new stimulation method in which an ultrasonic wave in a static magnetic field generates an electric field in an area of interest such as in the brain to modulate neuronal activities. However, the biophysical basis of simulating the neurons remains unknown. To address this problem, we perform a theoretical analysis based on a passive cable model to investigate the THS mechanism of neurons. Nerve tissues are conductive; an ultrasonic wave can move ions embedded in the tissue in a static magnetic field to generate an electric field（due to Lorentz force）.In this study, a simulation model for an ultrasonically induced electric field in a static magnetic field is derived. Then,based on the passive cable model, the analytical solution for the voltage distribution in a nerve tissue is determined. The simulation results showthat THS can generate a voltage to stimulate neurons. Because the THS method possesses a higher spatial resolution and a deeper penetration depth, it shows promise as a tool for treating or rehabilitating neuropsychiatric disorders.

关键词： Hall-effect stimulation passive cable model neurons

Attention and available long-term memory in an activation-based model

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Science China(Life Sciences) 2010年第6期53卷 743-752页

作者： LIU ZhaoMin1,GUO ChunYan2.3 & LUO Liang4 1 School of Sociology,China university of Political Science and Law,beijing 102.49,China 2.beijing key Laboratory of learning and Cognition,Department of Psychology,Capital normal university,beijing 100048,China 3 key Laboratory of Mental Health,Chinese Academy of Sciences,beijing 100101,China 4 state key Laboratory of {12. neuroscience and learning,beijing normal university,beijing 100875,China School of Sociology China University of Political Science and Law Beijing China beijing key Laboratory of {2. and Cognition Department of Psychology Capital Normal University Beijing China key Laboratory of Mental Health Chinese Academy of Sciences Beijing China state key Laboratory of {2. neuroscience and learning Beijing Normal University Beijing China

The influence of attention on memorizing related items and on available long-term memory (ALTM) was explored,showing that N400 of no-memory items was more negative than that of the memory *** results of the category comparison task indicated that information processing under attention-driven in WM determined the availability of related long-term memory,i.e.,specific content,which was formerly concerned or ignored,yielding different indirect semantic priming *** indicate that the orientation of conceptual attention leads the related representations of LTM to diverse activation patterns,supporting the activation-based model.

关键词： activation-based model attention available long-term memory event-related potentials

Inconspicuous anchoring effects generated by false information

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Progress in Natural Science:Materials International 2008年第11期18卷 1375-1382页

作者： Chen Qu~(a,b) Jun Wang~a yuejia Luo~(a,c,*) a state {2. Laboratory of cognitive neuroscience and learning,beijing normal university,beijing 100875,China b Center for studies of Psychological Application,South China normal university Guangzhou,510631,China c {2. Laboratory of Mental Health,Institute of Psychology,Chinese Academy of Sciences,beijing 100101,China state key Laboratory of {2. neuroscience and learning Beijing Normal University Beijing 100875 China Center for studies of Psychological Application South China Normal University Guangzhou 510631 China key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences Beijing 100101 China

The impact of false information on numerical judgments was examined on young normal subjects by an event-related potential(ERP) *** imitate the judgments in real world,we ensured the subjects acknowledged of the target *** behavioral results found that both uncertain information and false information assimilated the final estimates:higher after higher anchors and lower after lower anchors;and false information caused a weaker anchoring bias than uncertain *** results provided further electro- physiological evidence for the mechanism of *** the early phrase,it was an accessibility-dominated process in which two kinds of anchors elicited an N300 component related to the accessibility of anchors *** knowledge relevant to targets joined the process in the late phrase,which caused a larger amplitude of late positive component(LPC)for implausible lower anchors than that for plausible higher *** analysis showed that medial frontal gyrus,whose activity was suggested to signal the need of adjust- ment,was more reliable to explain the LPC elicited by implausible lower ***,we suggest that accessibility is facilitated when the external anchor is consistent with the world knowledge,and adjustment is initiated when the external anchor is inconsistent.

关键词： False anchors Anchoring effects Accessibility Adjustment ERP

An improved exponential filter for fast nonlinear registration of brain magnetic resonance images

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Progress in Natural Science:Materials International 2009年第6期19卷 759-767页

作者： Zhiying Long a, Li Yao a,b, Kewei Chen c, Danling Peng a a state key Laboratory of {2. neuroscience and learning, beijing normal university, beijing 100875, China b School of Information Science and Technology, beijing normal university, beijing 100875, China c Banner Alzheimer Institute (BAI) & Samaritan PET Center, Phoenix, AZ, USA state key Laboratory of {2. neuroscience and learning Beijing Normal University Beijing 100875 China School of Information Science and Technology Beijing Normal University Beijing 100875 China Banner Alzheimer Institute (BAI) & Samaritan PET Center Phoenix AZ USA

A linear elastic convolution filter was derived from the eigenfunctions of the Navier-Stokes differential operator by Bro-Nielsen in order to match images with large deformations. Due to the complexity of constructing the elastic convolution filter, the algorithm’s efficiency reduces rapidly with the increase in the image’s size. In our previous work, a simple two-sided exponential filter with high efficiency was proposed to approximate an elastic filter. However, its poor smoothness may degenerate the performance. In this paper, a new exponential filter was constructed by utilizing a modified nonlinear curve fitting method to approximate the elastic filter. The new filter’s good smoothness makes its performance comparable to an elastic filter. Its simple and separable form makes the algorithm’s speed faster than the elastic filter. Furthermore, our experiments demonstrated that the new filter was suitable for both the elastic and fluid models.

关键词： Exponential filter Nonlinear Registration Magnetic resonance imaging

Spatio-temporal pattern analysis of single-trial EEG signals recorded during visual object recognition

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Science China(Information Sciences) 2011年第12期54卷 2519-2527页

作者： WANG ChangMing 1 , HU XiaoPing 3 , YAO Li 1,2., XIONG Shi 2.& ZHANG JiaCai 2.1 National key Laboratory of cognitive {2. and learning, beijing normal university, beijing 100875, China 2.College of Information Science and Technology, beijing normal university, beijing 100875, China 3 Biomedical Imaging Technology Center, Emory university/Georgia Institute of Technology, Atlanta 3032., USA National key Laboratory of cognitive {2. and learning Beijing Normal University Beijing China Biomedical Imaging Technology Center Emory University/Georgia Institute of Technology Atlanta USA College of Information Science and Technology Beijing Normal University Beijing China

Object discrimination is a fundamental cognitive function for human brains. In this study, we utilized an analysis approach for single-trial electroencephalography (EEG) to analyze the spatio-temporal activation patterns of visual objects processing in human brains, and attempted to apply it to discriminate different visual objects. The spatial patterns were respectively extracted from scalp EEG and the reconstructed cortical sources, while the experiment participants were perceiving 4 different categories of visual objects (faces, buildings, cats and cars). By classifying the patterns extracted from single-trial EEG, the presented visual objects could be discriminated by a computer, and the classification accuracies may provide a quantitative index to evaluate the spatial differences of the brain activations related to different visual objects. Our results demonstrated that the spatial patterns on both the scalp and the sources levels resulted in higher classification accuracies than chance rate. We also examined the classification results using temporally non-overlapping time intervals of different event-related potential (ERP) components. The temporal changes of classification accuracies may reflect the temporal distribution of the discriminative information in the EEG responses. The present pattern extraction and classification methods may compose a computational model for single-trial EEG data analysis in investigations of the spatio-temporal activation patterns for object recognition. These spatio-temporal patterns in EEG may be useful to identifying the discriminative spatial areas and time stages to improve the accuracies and efficiencies of object discrimination. In addition, investigating and utilizing humans'cognitive mechanisms of object recognition may improve computers' processing efficiency of visual information.

关键词： EEG spatio-temporal pattern object recognition single-trial analysis visual information processing

Resting-state functional MRI:Algorithms and application to brain disorders

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Resting-state functional MRI:Algorithms and application to b...

Early ERP effects on the scaling of spatial attention in visual search

中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： yu-fengzang {2. key Laboratory of cognitive neuroscience and learning,beijing normal university,beijing,100875

＜正＞Blood oxygenation level dependent（BOLD） functional magnetic resonance imaging（fMRI） is being widely used for detection of the brain activation during a specific *** term activation means a significant signal change evoked by a target task relative to a baseline or control *** baseline activity is usually taken as ***,the spontaneous or on-going brain activity is of great *** and EEG are two useful techniques for studying resting-state brain function in clinical *** with PET,the resting-state fMRI（RS-fMRI） has no radioactivity and has higher temporal *** with EEG or MEG,RS-fMRI has higher spatial *** the aspect of computation,the algorithms for RS-fMRI could be divided into two categories,one is for integration and the other is for *** for integration mainly focus on the functional relationship,usually called functional connectivity, among remote brain *** most popular algorithm for integration is linear correlation between the time series of remote brain areas（Biswal et al.,1995,MRM）.An example of this method for brain disorder is that,in multiple sclerosis patients, the functional connectivity between the bilateral primary sensorimotor cortices was reduced due to the lesion in the corpus callosum（Lowe et al.,2.02.Radiology）.Another method for integration is spatial-independent component analysis （sICA）.sICA separates the 4D brain into many spatially independent networks（components）（Kiviniemi et al.,2.03, NeuroImage）.For example,decreased coactivation in the default mode network has been reported in Alzheimer’s disease （AD） or mild {2. impairment（MCI）（Greicius et al.,2.04,PNAS）.Algorithms for segregation focus on the local features of the spontaneous brain *** homogeneity（ReHo） measures the local synchronization of the time series of voxels within a given area（Zang et al.,2.04,Neurolmage）.ReHo has been used in many brain disorders including schiz

关键词： resting-state fMRI functional connectivity independent component analysis regional homogeneity amplitude of low frequency fluctuation

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Progress in Natural Science:Materials International 2008年第4期18卷 381-386页

作者： Ya-Nan Niu a,b, Jing-Han Wei a, yue-Jia Luo a,c, a Institute of Psychology, Chinese Academy of Sciences, beijing 100101, China b Graduate School of Chinese Academy of Sciences, beijing 100049, China c state key Laboratory of cognitive neuroscience and learning, beijing normal university, 19 Xin-wai Avenue, beijing 100875, China Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Graduate School of Chinese Academy of Sciences Beijing 100049 China state key Laboratory of {2. neuroscience and learning Beijing Normal University 19 Xin-wai Avenue Beijing 100875 China

This article describes the examination of the spatial ’scaling’ effect of visual attention with the technique of event-related potential (ERP). Eighteen participants were involved in a visual search task in which the cue-target paradigm was used. The search array was three concentric circles consisting of randomly selected English letters that were equally distributed in each circle. The behavioral and ERP data were recorded, respectively. The behavioral results showed that the response time increased and the response accuracy decreased with the increase of precue size. The ERPs amplitude of P1 and N1 components evoked by search array increased with the reduction of precue size. However, the latencies of these ERP components did not show significant differences between conditions. The hierarchical data of both behavioral assessment and ERPs provided evidence for the spatial ’scaling’ effect of visual attention. The amplitudes of P1 and N1 components may be used as indices to examine the effect of spatial ’scaling’. In different tasks, the display-set size of stimuli and the task complexity may be important factors that affect the attention allocation.

关键词： Visual search Spatial attention ‘Scaling’ effect Event-related potential

Effect of focused ultrasound stimulation at different ultrasonic power levels on the local field potential power spectrum

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Chinese Physics B 2015年第8期24卷 646-650页

作者：袁毅路承彪李小俚 Institute of Electrical Engineering Yanshan University state key Laboratory of {2. neuroscience and learning & IDG/Mc Govern Institute for Brain Research Beijing Normal University Center for Collaboration and Innovation in Brain and learning Sciences Beijing Normal University

Local field potential(LFP) signals of the rat hippocampus were recorded under noninvasive focused ultrasound stimulation(FUS) with different ultrasonic powers. The LFP mean absolute power was calculated with the Welch algorithm at the delta, theta, alpha, beta, and gamma frequency bands. The experimental results demonstrate that the LFP mean absolute power at different frequency bands increases as the ultrasound power increases.

关键词： focused ultrasound stimulation local field potential power spectrum

The role of different cues in the brain mechanism on visual spatial attention

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Progress in Natural Science:Materials International 2006年第10期16卷 1045-1050页

作者： SONG Weiqun, LUO yuejia, CHI Song, JI Xunming, LING Feng, ZHAO Lun, WANG Maobin and SHI Jiannong ( Department of Rehabilitation, Xuanwu Hospital, Capital university of Medical Science, {2. 100053, China state key Laboratory of cognitive neuroscience and learning, beijing normal university, {2. 100875, China School of Psychology, Southwest university, Chongqing 400715, China key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, {2. 100101, China Department of Neurology, Affiliated Hospital of Qingdao university, Medical College, Qingdao 2.6003, China Department of Neurology, Xuanwu Hospital, Capital university of Medical Science, {2. 100053, China Institute of Linguistics, Xuzhou normal university, Xuzhou 2.1116, China) Department of Rehabilitation Xuanwu Hospital Capital University of Medical Science Beijing 100053 China state key Laboratory of {2. neuroscience and learning Beijing Normal University Beijing 100875 China School of Psychology Southwest University Chongqing 400715 China key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Department of Neurology Affiliated Hospital of Qingdao University Medical College Qingdao 266003 China Department of Neurology Xuanwu Hospital Capital University of Medical Science Beijing 100053 China Institute of Linguistics Xuzhou Normal University Xuzhou 221116 China

The visual spatial attention mechanism in the brain was studied in 16 young subjects through the visual search paradigm of precue-target by the event-related potential (ERP) technique, with the attentive ranges cued by different scales of Chinese character and region cues. The results showed that the response time for Chinese character cues was much longer than that for region cues especially for small region cues. With the exterior interferences, the target stimuli recognition under region cues was much quicker than that under Chinese character cues. Compared with that under region cues, targets under Chinese character cues could lead to increase of the posterior P1, decrease of the N1 and increase of the P2. It should also be noted that the differences between region cues and Chinese character cues were affected by the interference types. Under exterior interferences, no significant difference was found between region cues and Chinese character cues; however, it was not the case under the interior interferences. Considering the difference between the exterior interferences and the interior interferences, we could conclude that with the increase of difficulty in target recognition there was obvious difference in the consumption of anterior frontal resources by target stimuli under the two kinds of cues.

关键词： visual spatial attention cue scale event-related potential (ERP) Chinese character cues region cues.