检索结果-内蒙古大学图书馆

fMRI of the Face-processing Network in the Ventral Temporal Lobe of Awake and Anesthetized Macaques

NEURON 2011年第2期70卷 352-362页

作者： Ku, Shih-Pi Tolias, Andreas S. Logothetis, Nikos K. Goense, Jozien Max Planck Inst Biol Cybernet D-72076 Tubingen Germany Baylor Coll Med Dept Neurosci Houston TX 77030 USA Michael E DeBakey VA Med Ctr Houston TX 77030 USA Rice Univ Dept Computat & Appl Math Houston TX 77005 USA Univ Manchester Div Imaging Sci & Biomed Engn Manchester M13 9PT Lancs England

The primate brain features specialized areas devoted to processing of faces, which human imaging studies localized in the superior temporal sulcus (STS) and ventral temporal cortex. Studies in macaque monkeys, in contrast, revealed face selectivity predominantly in the STS. While this discrepancy could result from a true species difference, it may simply be the consequence of technical difficulties in obtaining high-quality MR images from the ventral temporal lobe. By using an optimized fMRI protocol we here report face-selective areas in ventral TE, the parahippocampal cortex, the entorhinal cortex, and the hippocampus of awake macaques, in addition to those already known in the STS. Notably, the face-selective activation of these memory-related areas was observed although the animals were passively viewing and it was preserved even under anesthesia. These results point to similarly extensive cortical networks for face processing in humans and monkeys and highlight potential homologs of the human fusiform face area.

关键词： Anesthesia Anesthetics/pharmacology Animals Face image processing, computer-assisted/methods Macaca mulatta Magnetic Resonance Imaging/methods Male Neural Pathways/blood supply Neural Pathways/drug effects Neural Pathways/physiology Oxygen/blood Photic Stimulation/methods Recognition (Psychology)/drug effects Recognition (Psychology)/physiology Temporal Lobe/blood supply Temporal Lobe/drug effects Wakefulness

来源：评论

学校读者我要写书评

暂无评论

The Brain under Self-Control: Modulation of Inhibitory and Monitoring Cortical Networks during Hypnotic Paralysis

引用

NEURON 2009年第6期62卷 862-875页

作者： Cojan, Yann Waber, Lakshmi Schwartz, Sophie Rossier, Laurent Forster, Alain Vuilleumier, Patrik Univ Geneva Dept Neurosci Univ Med Sch Geneva Switzerland Univ Geneva Ctr Neurosci Geneva Switzerland Univ Hosp Geneva Dept Addict Geneva Switzerland Univ Hosp Geneva Dept Anesthesiol Geneva Switzerland Univ Fribourg Dept Psychol CH-1700 Fribourg Switzerland

Brain mechanisms of hypnosis are poorly known. Cognitive accounts proposed that executive attentional systems may cause selective inhibition or disconnection of some mental operations. To assess motor and inhibitory brain circuits during hypnotic paralysis, we designed a go-nogo task while volunteers underwent functional magnetic resonance imaging (fMRI) in three conditions: normal state, hypnotic left-hand paralysis, and feigned paralysis. Preparatory activation arose in right motor cortex despite left hypnotic paralysis, indicating preserved motor intentions, but with concomitant increases in precuneus regions that normally mediate imagery and self-awareness. Precuneus also showed enhanced functional connectivity with right motor cortex. Right frontal areas subserving inhibition were activated by nogo trials in normal state and by feigned paralysis, but irrespective of motor blockade or execution during hypnosis. These results suggest that hypnosis may enhance self-monitoring processes to allow internal representations generated by the suggestion to guide behavior but does not act through direct motor inhibition.

关键词： Analysis of Variance Attention Brain Mapping Brain Mapping Decision Making/physiology Functional Laterality/physiology Humans Hypnosis/methods image processing, computer-assisted/methods Inhibition (Psychology) Magnetic Resonance Imaging/methods Motor Cortex/blood supply Motor Cortex/physiopathology Movement/physiology Neural Pathways/physiopathology Neuropsychological Tests Oxygen/blood Paralysis/etiology Paralysis/pathology Psychomotor Performance/physiology Reaction Time/physiology Self Concept

来源：评论

学校读者我要写书评

暂无评论

Learning partially directed functional networks from meta-analysis imaging data

引用

NEUROimage 2010年第2期49卷 1372-1384页

作者： Neumann, Jane Fox, Peter T. Turner, Robert Lohmann, Gabriele Max Planck Inst Human Cognit & Brain Sci Dept Neurophys D-04103 Leipzig Germany Univ Texas Hlth Sci Ctr San Antonio Res Imaging Ctr San Antonio TX USA

We Propose a new exploratory method for the discovery of partially directed functional networks from fMRI meta-analysis data. The method performs structure learning of Bayesian networks in search of directed probabilistic dependencies between brain regions. Learning is based on the co-activation of brain regions observed across several independent imaging experiments. In a series of simulations, we first demonstrate the reliability of the method. We then present the application of our approach in an extensive meta-analysis including several thousand activation coordinates from more than 500 imaging studies. Results show that our method is able to automatically infer Bayesian networks that capture both directed and undirected probabilistic dependencies between a number of brain regions, including regions that are frequently observed in motor-related and cognitive control tasks. (C) 2009 Elsevier Inc. All rights reserved.

关键词： Artificial Intelligence Automation Bayes Theorem Brain/physiology Cluster Analysis computer Simulation Humans image processing, computer-assisted/methods Magnetic Resonance Imaging/methods Meta-Analysis as Topic Neural Pathways/physiology Probability

来源：评论

学校读者我要写书评

暂无评论

Noninvasive visualization of human dopamine dynamics from PET images

引用

NEUROimage 2010年第1期51卷 135-144页

作者： Morris, E. D. Constantinescu, C. C. Sullivan, J. M. Normandin, M. D. Christopher, L. A. Indiana Univ Purdue Univ Dept Biomed Engn Indianapolis IN 46202 USA Purdue Univ Dept Biomed Engn W Lafayette IN 47907 USA Indiana Univ Sch Med Dept Radiol Indianapolis IN 46202 USA Univ Calif Irvine Dept Psychiat & Human Behav Irvine CA 92717 USA Indiana Univ Purdue Univ Dept Elect & Comp Engn Indianapolis IN 46202 USA

We recently introduced strategies for extracting temporal patterns of brain dopamine fluctuations from dynamic positron emission tomography (PET) data using the tracer [11C]-raclopride. Each of our methods yields a collection of time-concentration curves for endogenous dopamine. Given a spatially dense collection of curves (i.e., one at every voxel in a region of interest), we produce image volumes of dopamine (DA) concentration, DA( X, t), at multiple voxel locations and each time-frame. The volume over time-frames constitutes a 4D dataset that can be thought of as a DA "movie". There are a number of ways to visualize such data. Viewing cine loops of a slice through the DA volume is one way. Creating images of dopamine peak-time, T-peak(X), derived from a movie, is another. Each visualization may reveal spatio-temporal patterns of neurotransmitter activity heretofore unobservable. We conducted an initial validation experiment in which identical DA responses were induced by an identical task, initiated at different times by the same subject, in two separate PET scans. A comparison of the resulting T-peak(X) images revealed a large contiguous cluster of striatal voxels, on each side, whose DA timing was consistent with the relative timing of the tasks. Hence, the DA movies and their respective peak-time images were shown to be new types of functional images that contain bonafide timing information about a neurotransmitter's response to a stimulus. (C) 2009 Elsevier Inc. All rights reserved.

关键词： Algorithms Brain/metabolism Brain/radionuclide imaging Brain Mapping/methods Brain Mapping/methods Cluster Analysis Dopamine/metabolism Fingers/physiology Humans image processing, computer-assisted/methods Imaging, Three-Dimensional/methods Male Motor Activity/physiology Positron-Emission Tomography/methods Raclopride Raclopride Time Factors Video Recording

来源：评论

学校读者我要写书评

暂无评论

Population-scale three-dimensional reconstruction and quantitative profiling of microglia arbors

引用

BIOINFORMATICS 2015年第13期31卷 2190-2198页

作者： Megjhani, Murad Rey-Villamizar, Nicolas Merouane, Amine Lu, Yanbin Mukherjee, Amit Trett, Kristen Chong, Peter Harris, Carolyn Shain, William Roysam, Badrinath Univ Houston Dept Elect & Comp Engn Houston TX 77004 USA Seattle Childrens Hosp Ctr Integrat Brain Res Seattle WA 98101 USA Cold Spring Harbor Lab Cold Spring Harbor NY 11724 USA

Motivation: The arbor morphologies of brain microglia are important indicators of cell activation. This article fills the need for accurate, robust, adaptive and scalable methods for reconstructing 3-D microglial arbors and quantitatively mapping microglia activation states over extended brain tissue regions. Results: Thick rat brain sections (100-300 mm) were multiplex immunolabeled for IBA1 and Hoechst, and imaged by step-and-image confocal microscopy with automated 3-D image mosaicing, producing seamless images of extended brain regions (e.g. 5903 x 9874 x 229 voxels). An over-complete dictionary-based model was learned for the image-specific local structure of microglial processes. The microglial arbors were reconstructed seamlessly using an automated and scalable algorithm that exploits microglia-specific constraints. This method detected 80.1 and 92.8% more centered arbor points, and 53.5 and 55.5% fewer spurious points than existing vesselness and LoG-based methods, respectively, and the traces were 13.1 and 15.5% more accurate based on the DIADEM metric. The arbor morphologies were quantified using Scorcioni's L-measure. Coifman's harmonic co-clustering revealed four morphologically distinct classes that concord with known microglia activation patterns. This enabled us to map spatial distributions of microglial activation and cell abundances.

关键词： Algorithms Animals Brain/cytology Brain Mapping/methods Brain Mapping/methods image processing, computer-assisted/methods Imaging, Three-Dimensional/methods Mice Microglia/cytology Pattern Recognition, Automated Rats Software

来源：评论

学校读者我要写书评

暂无评论

Automated 3-D extraction of inner and outer surfaces of cerebral cortex from MRI

引用

NEUROimage 2000年第3期12卷 340-356页

作者： MacDonald, D Kabani, N Avis, D Evans, AC Montreal Neurol Inst McConnell Brain Imaging Ctr Montreal PQ H3A 2B4 Canada McGill Univ Sch Comp Sci Montreal PQ Canada

Automatic computer processing of large multidimensional images such as those produced by magnetic resonance imaging (MRI) is greatly aided by deformable models, which are used to extract, identify, and quantify specific neuroanatomic structures. A general method of deforming polyhedra is presented here, with two novel features, First, explicit prevention of self-intersecting surface geometries is provided, unlike conventional deformable models, which use regularization constraints to discourage but not necessarily prevent such behavior. Second, deformation of multiple surfaces with intersurface proximity constraints allows each surface to help guide other surfaces into place using model-based constraints such as expected thickness of an anatomic surface. These two features are used advantageously to identify automatically the total surface of the outer and inner boundaries of cerebral cortical gray matter from normal human MR images, accurately locating the depths of the sulci, even where noise and partial volume artifacts in the image obscure the visibility of sulci. The extracted surfaces are enforced to be simple two-dimensional manifolds (having the topology of a sphere), even though the data may have topological holes, This automatic 3-D cortex segmentation technique has been applied to 150 normal subjects, simultaneously extracting both the gray/white and gray/cerebrospinal fluid interface from each individual. The collection of surfaces has been used to create a spatial map of the mean and standard deviation for the location and the thickness of cortical gray matter. Three alternative criteria for defining cortical thickness at each cortical location were developed and compared. These results are shown to corroborate published postmortem and in vivo measurements of cortical thickness. (C) 2000 Academic Press.

关键词： Algorithms Brain Mapping Brain Mapping Cerebral Cortex/anatomy & histology Cerebral Cortex/physiology Humans image processing, computer-assisted/methods Magnetic Resonance Imaging/methods Models, Neurological Reproducibility of Results Terminology as Topic

来源：评论

学校读者我要写书评

暂无评论

DiSWOP: a novel measure for cell-level protein network analysis in localized proteomics image data

引用

BIOINFORMATICS 2014年第3期30卷 420-427页

作者： Kovacheva, Violeta N. Khan, Adnan M. Khan, Michael Epstein, David B. A. Rajpoot, Nasir M. Univ Warwick Dept Syst Biol Coventry CV4 7AL W Midlands England Univ Warwick Dept Comp Sci Coventry CV4 7AL W Midlands England Univ Warwick Sch Life Sci Coventry CV4 7AL W Midlands England Univ Warwick Math Inst Coventry CV4 7AL W Midlands England Qatar Univ Dept Comp Sci & Engn Doha Qatar

Motivation: New bioimaging techniques have recently been proposed to visualize the colocation or interaction of several proteins within individual cells, displaying the heterogeneity of neighbouring cells within the same tissue specimen. Such techniques could hold the key to understanding complex biological systems such as the protein interactions involved in cancer. However, there is a need for new algorithmic approaches that analyze the large amounts of multi-tag bioimage data from cancerous and normal tissue specimens to begin to infer protein networks and unravel the cellular heterogeneity at a molecular level. Results: The proposed approach analyzes cell phenotypes in normal and cancerous colon tissue imaged using the robotically controlled Toponome Imaging System microscope. It involves segmenting the 4',6-diamidino-2-phenylindole-labelled image into cells and determining the cell phenotypes according to their protein-protein dependence profile. These were analyzed using two new measures, Difference in Sums of Weighted cO-dependence/Anti-co-dependence profiles (DiSWOP and DiSWAP) for overall co-expression and anti-co-expression, respectively. These novel quantities were extracted using 11 Toponome Imaging System image stacks from either cancerous or normal human colorectal specimens. This approach enables one to easily identify protein pairs that have significantly higher/lower co-expression levels in cancerous tissue samples when compared with normal colon tissue.

关键词： Algorithms Colonic Neoplasms/metabolism Humans image processing, computer-assisted/methods Phenotype Protein Interaction Mapping/methods Proteomics/methods

来源：评论

学校读者我要写书评

暂无评论

High binaural coherence determines successful sound localization and increased activity in posterior auditory areas

引用

NEURON 2005年第6期47卷 893-905页

作者： Zimmer, U Macaluso, E Fdn Santa Lucia Neuroimaging Lab I-00179 Rome Italy

Our brain continuously receives complex combinations of sounds originating from different sources and relating to different events in the external world. Timing differences between the two ears can be used to localize sounds in space, but only when the inputs to the two ears have similar spectrotemporal profiles (high binaural coherence). We used fMRI to investigate any modulation of auditory responses by binaural coherence. We assessed how processing of these cues depends on whether spatial information is task relevant and whether brain activity correlates with subjects' localization performance. We found that activity in Heschl's gyrus increased with increasing coherence, irrespective of whether localization was task relevant. Posterior auditory regions also showed increased activity for high coherence, primarily when sound localization was required and subjects successfully localized sounds. We conclude that binaural coherence cues are processed throughout the auditory cortex and that these cues are used in posterior regions for successful auditory localization.

关键词： Acoustic Stimulation/methods Adolescent Adult Auditory Cortex/blood supply Auditory Cortex/physiology Brain Mapping Brain Mapping Cues Female Functional Laterality/physiology Hearing/physiology Humans image processing, computer-assisted/methods Magnetic Resonance Imaging/methods Male Oxygen/blood Psychophysics/methods Sound Localization/physiology Space Perception/physiology

来源：评论

学校读者我要写书评

暂无评论

Enhanced identification of BOLD-like components with multi-echo simultaneous multi-slice (MESMS) fMRI and multi-echo ICA

引用

NEUROimage 2015年 112卷 43-51页

作者： Olafsson, Valur Kundu, Prantik Wong, Eric C. Bandettini, Peter A. Liu, Thomas T. Univ Pittsburgh Neurosci Imaging Ctr Pittsburgh PA 15203 USA Icahn Inst Med Mt Sinai Brain Imaging Ctr New York NY 10029 USA Icahn Inst Med Mt Sinai Translat & Mol Imaging Inst New York NY 10029 USA Univ Calif San Diego Ctr Funct Magnet Resonance Imaging La Jolla CA 92093 USA Univ Calif San Diego Dept Radiol La Jolla CA 92093 USA Univ Calif San Diego Dept Psychiat La Jolla CA 92093 USA NIMH Sect Funct Imaging Methods Bethesda MD 20892 USA NIMH Funct MRI Core Facil Bethesda MD 20892 USA Univ Calif San Diego Dept Bioengn La Jolla CA 92093 USA

The recent introduction of simultaneous multi-slice (SMS) acquisitions has enabled the acquisition of blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) data with significantly higher temporal sampling rates. In a parallel development, the use of multi-echo fMRI acquisitions in conjunction with a multi-echo independent component analysis (ME-ICA) approach has been introduced as a means to automatically distinguish functionally-related BOLD signal components from signal artifacts, with significant gains in sensitivity, statistical power, and specificity. In this work, we examine the gains that can be achieved with a combined approach in which data obtained with a multi-echo simultaneous multi-slice (MESMS) acquisition are analyzed with ME-ICA. We find that ME-ICA identifies significantly more BOLD-like components in the MESMS data as compared to data acquired with a conventional multi-echo single-slice acquisition. We demonstrate that the improved performance of MESMS derives from both an increase in the number of temporal samples and the enhanced ability to filter out high-frequency artifacts. (C) 2015 Elsevier Inc. All rights reserved.

关键词： Adult Artifacts Echo-Planar Imaging/methods Echo-Planar Imaging/statistics & numerical data Female Humans image processing, computer-assisted/methods image processing, computer-assisted/statistics & numerical data Magnetic Resonance Imaging/methods Magnetic Resonance Imaging/statistics & numerical data Male Oxygen/blood Principal Component Analysis

来源：评论

学校读者我要写书评

暂无评论

Effects of diffusion weighting schemes on the reproducibility of DTI-derived fractional anisotropy, mean diffusivity, and principal eigenvector measurements at 1.5T

引用

NEUROimage 2007年第4期36卷 1123-1138页

作者： Landman, Bennett A. Farrell, Jonathan A. D. Jones, Craig K. Smith, Seth A. Prince, Jerry L. Mori, Susumu Johns Hopkins Univ Sch Med Russell H Morgan Dept Radiol & Radiol Sci Baltimore MD 21205 USA Johns Hopkins Univ Sch Med Dept Biomed Engn Baltimore MD 21205 USA Kennedy Krieger Inst FM Kirby Res Ctr Funct Brain Imaging Baltimore MD 21205 USA Johns Hopkins Univ Sch Med Dept Biophys & Biophys Chem Baltimore MD 21205 USA Johns Hopkins Univ Dept Elect & Comp Engn Baltimore MD 21205 USA

Diffusion tensor imaging (DTI) is used to study tissue composition and architecture in vivo. To increase the signal to noise ratio (SNR) of DTI contrasts, studies typically use more than the minimum of 6 diffusion weighting (DW) directions or acquire repeated observations of the same set of DW directions. Simulation-based studies have sought to optimize DTI acquisitions and suggest that increasing the directional resolution of a DTI dataset (i.e., the number of distinct directions) is preferable to repeating observations, in an equal scan time comparison. However, it is not always clear how to translate these recommendations into practice when considering physiological noise and scanner stability. Furthermore, the effect of different DW schemes on ht vivo DTI findings is not fully understood. This study characterizes how the makeup of a DW scheme, in terms of the number of directions, impacts the precision and accuracy of in vivo fractional anisotropy (FA), mean diffusivity, (MD), and principal eigenvector (PEV) findings. Orientation dependence of DTI reliability is demonstrated in vivo and a principled theoretical framework is provided to support and interpret findings with simulation results. As long as sampling orientations are well balanced, differences in DTI contrasts due to different DW schemes are shown to be small relative to intra-session variability. These differences are accentuated at low SNR, while minimized at high SNR. This result suggests that typical clinical studies, which use similar protocols but different ell-balanced DW schemes, are readily comparable within the experimental precision. (C) 2007 Elsevier Inc. All rights reserved.

关键词： Adult Anisotropy Artifacts Brain/anatomy & histology computer Simulation Diffusion Magnetic Resonance Imaging/methods Humans image processing, computer-assisted/methods Male Monte Carlo Method Sensitivity and Specificity Software

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：