检索结果-内蒙古大学图书馆

A dual-route perspective on brain activation in response to visual words: Evidence for a length by lexicality interaction in the visual word form area (VWFA)

引用

NEUROimage 2010年第3期49卷 2649-2661页

作者： Schurz, Matthias Sturm, Denise Richlan, Fabio Kronbichler, Martin Ladurner, Gunther Wimmer, Heinz Salzburg Univ Dept Psychol A-5020 Salzburg Austria Salzburg Univ Ctr Neurocognit Res A-5020 Salzburg Austria Paracelsus Private Med Univ Christian Doppler Clin Dept Neurol Salzburg Austria

Based on our previous work, we expected the Visual Word Form Area (VWFA) in the left ventral visual pathway to be engaged by both whole-word recognition and by serial sublexical coding of letter strings. To examine this double function, a phonological lexical decision task (i.e, "Does xxx sound like an existing word?") presented short and long letter strings of words. pseudohomophones, and pseudowords (e g, Taxi, Taksi and Tazi) Main findings were that the length effect for words was limited to occipital regions and absent in the VWFA In contrast, a marked length effect for pseudowords was found throughout the ventral Visual pathway including the VWFA, as well as in regions presumably engage(] by Visual attention and silent-articulatory processes. The length by lexicality interaction on brain activation corresponds to well-established behavioral findings of a length by lexicality interaction on naming latencies and speaks for the engagement of the VWFA by both lexical and sublexical processes (C) 2009 Elsevier Inc All rights reserved.

关键词： Adolescent Brain/anatomy & histology Brain/physiology Brain Mapping Brain Mapping Functional Laterality/physiology Humans image processing, computer-assisted Male Pattern Recognition, Visual/physiology Photic Stimulation Reading Visual Pathways/anatomy & histology Visual Pathways/physiology Young Adult

来源：评论

学校读者我要写书评

暂无评论

Neural systems supporting lexical search guided by letter and semantic category cues: A self-paced overt response fMRI study of verbal fluency

引用

NEUROimage 2010年第1期49卷 1099-1107页

作者： Birn, Rasmus M. Kenworthy, Lauren Case, Laura Caravella, Rachel Jones, Tyler B. Bandettin, Peter A. Martin, Alex NIMH Lab Brain & Cognit Bethesda MD 20892 USA Childrens Natl Med Ctr Ctr Autism Spectrum Disorders Washington DC 20010 USA

Verbal fluency tasks have been widely. used to evaluate language and executive control processes in the human brain. FMRI studies of verbal fluency, however, have used either silent word generation (which provides no behavioral measure) or cued generation of single words in order to contend with speech-related motion artifacts. In this study, we use a recently developed paradigm design to investigate the neural correlates of verbal fluency during overt, free recall, word generation so that performance and brain activity could be evaluated under conditions that more closely mirror standard behavioral test demands. We investigated verbal fluency to both letter and category cues in order to evaluate differential involvement of specific frontal and temporal lobe sites as a function of retrieval cue type, as suggested by previous neuropsychological and neuroimaging investigations. in addition, we incorporated both a task switching manipulation and an automatic speech condition in order to modulate the demand placed on executive functions. We found greater activation in the left hemisphere during category and letter fluency tasks, and greater right hemisphere activation during automatic speech. We also found that letter and category fluency tasks were associated with differential involvement of specific regions of the frontal and temporal lobes. These findings provide converging evidence that letter and category fluency performance is dependent on partially distinct neural circuitry. They also provide strong evidence that verbal fluency can be successfully evaluated in the MR environment using overt, self-paced, responses. Published by Elsevier Inc.

关键词： Adult Artifacts Brain/physiology Cues Echo-Planar Imaging Executive Function/physiology Female Frontal Lobe/physiology Humans image processing, computer-assisted Magnetic Resonance Imaging Male Middle Aged Photic Stimulation Psycholinguistics Reading Temporal Lobe/physiology Young Adult

来源：评论

学校读者我要写书评

暂无评论

Phonological repetition-suppression in bilateral superior temporal sulci

引用

NEUROimage 2010年第1期49卷 1018-1023页

作者： Vaden, Kenneth I., Jr. Muftuler, L. Tugan Hickok, Gregory Univ Calif Irvine Dept Cognit Sci Irvine CA 92697 USA Univ Calif Irvine Tu & Yuen Ctr Funct Oncoimaging Irvine CA 92697 USA

Evidence has accumulated that posterior superior temporal sulcus (STS) is critically involved in phonological processing during speech perception, although there are conflicting accounts regarding the degree of lateralization. The current fMRI experiment aimed to identify phonological processing during speech perception through repetition-suppression effects. Repetition-suppression occurs when brain activity decreases from repetitive presentation of stimulus characteristics, in regions of cortex that process those characteristics. We manipulated the degree of phonological repetition among words in short lists to obtain systematic decreases in brain response, indicative of phonological processing. The fMRI experiment presented seventeen participants with recorded wordlists, of low, medium, or high phonological repetition, defined by how many phonemes were shared among words. Bilaterally, middle STS demonstrated activity differences consistent with our prediction of repetition-suppression, as responses decreased systematically with each increase in phonological repetition. Phonological repetition-suppression in bilateral STS converges with neuroimaging evidence for phonological processing, and word deafness resulting from bilateral superior temporal lesions. (C) 2009 Elsevier Inc. All rights reserved.

关键词： Acoustic Stimulation Adult Female Functional Laterality/physiology Humans image processing, computer-assisted Magnetic Resonance Imaging Male Psycholinguistics Speech/physiology Speech Perception/physiology Temporal Lobe/physiology Young Adult

来源：评论

学校读者我要写书评

暂无评论

The oscillating brain: Complex and reliable

引用

NEUROimage 2010年第2期49卷 1432-1445页

作者： Zuo, Xi-Nian Di Martino, Adriana Kelly, Clare Shehzad, Zarrar E. Gee, Dylan G. Klein, Donald F. Castellanos, F. Xavier Biswal, Bharat B. Milham, Michael P. NYU Ctr Child Study Phyllis Green & Randolph Cowen Inst Pediat Neuros New York NY USA Nathan S Kline Inst Psychiat Res Orangeburg NY 10962 USA Univ Med & Dent New Jersey Dept Radiol Newark NJ 07103 USA Columbia Univ Coll Phys & Surg Dept Psychiat New York NY 10032 USA

The human brain is a complex dynamic system capable of generating a multitude of oscillatory waves in support of brain function. Using fMRI, we examined the amplitude of spontaneous low-frequency oscillations (LFO) observed in the human resting brain and the test-retest reliability of relevant amplitude measures. We confirmed prior reports that gray matter exhibits higher LFO amplitude than white matter. Within gray matter, the largest amplitudes appeared along mid-brain structures associated with the "default-mode" network. Additionally, we found that high-amplitude LFO activity in specific brain regions was reliable across time. Furthermore, parcellation-based results revealed significant and highly reliable ranking orders of LFO amplitudes among anatomical parcellation units. Detailed examination of individual low frequency bands showed distinct spatial profiles. Intriguingly, LFO amplitudes in the slow-4 (0.027-0.073 Hz) band, as defined by Buzsaki et al., were most robust in the basal ganglia, as has been found in spontaneous electrophysiological recordings in the awake rat. These results suggest that amplitude measures of LFO can contribute to further between-group characterization of existing and future "resting-state" fMRI datasets. (C) 2009 Elsevier Inc. All rights reserved.

关键词： Brain/physiology Brain Mapping Brain Mapping Female Humans image processing, computer-assisted Magnetic Resonance Imaging Male Nerve Fibers, Myelinated/physiology Nerve Fibers, Unmyelinated/physiology Periodicity Reproducibility of Results Rest/physiology Time Factors Young Adult

来源：评论

学校读者我要写书评

暂无评论

Discovering genetic associations with high-dimensional neuroimaging phenotypes: A sparse reduced-rank regression approach

引用

NEUROimage 2010年第3期53卷 1147-1159页

作者： Vounou, Maria Nichols, Thomas E. Montana, Giovanni Univ London Imperial Coll Sci Technol & Med Dept Math Stat Sect London SW7 2AZ England Univ Warwick Dept Stat Coventry CV4 7AL W Midlands England Univ Warwick Warwick Mfg Grp Coventry CV4 7AL W Midlands England

There is growing interest in performing genome-wide searches for associations between genetic variants and brain imaging phenotypes. While much work has focused on single scalar valued summaries of brain phenotype, accounting for the richness of imaging data requires a brain-wide, genome-wide search. In particular, the standard approach based on mass-univariate linear modelling (MULM) does not account for the structured patterns of correlations present in each domain. In this work, we propose sparse reduced rank regression (sRRR), a strategy for multivariate modelling of high-dimensional imaging responses (measurements taken over regions of interest or individual voxels) and genetic covariates (single nucleotide polymorphisms or copy number variations), which enforces sparsity in the regression coefficients. Such sparsity constraints ensure that the model performs simultaneous genotype and phenotype selection. Using simulation procedures that accurately reflect realistic human genetic variation and imaging correlations, we present detailed evaluations of the sRRR method in comparison with the more traditional MULM approach. In all settings considered, sRRR has better power to detect deleterious genetic variants compared to MULM. Important issues concerning model selection and connections to existing latent variable models are also discussed. This work shows that sRRR offers a promising alternative for detecting brain-wide, genome-wide associations. Crown Copyright (c) 2010 Published by Elsevier Inc. All rights reserved.

关键词： Brain/anatomy & histology Brain Mapping/methods Brain Mapping/methods Genome-Wide Association Study Genotype Humans image processing, computer-assisted Magnetic Resonance Imaging Models, Neurological Models, Statistical Phenotype Polymorphism, Single Nucleotide Quantitative Trait, Heritable Regression Analysis ROC Curve

来源：评论

学校读者我要写书评

暂无评论

Dynamic in vivo imaging of cerebral blood flow and blood-brain barrier permeability

引用

NEUROimage 2010年第1期49卷 337-344页

作者： Prager, Ofer Chassidim, Yoash Klein, Chen Levi, Haviv Shelef, Ilan Friedman, Alon Ben Gurion Univ Negev Fac Hlth Sci Dept Physiol Zlotowski Ctr Neurosci IL-84105 Beer Sheva Israel Soroka Univ Med Ctr Dept Physiol Beer Sheva Israel Soroka Univ Med Ctr Dept Neurosurg Beer Sheva Israel Soroka Univ Med Ctr Dept Neuroradiol Beer Sheva Israel

The brain is characterized by an extremely rich blood supply, regulated by changes in blood vessel diameter and blood flow, depending on metabolic demands. The blood-brain barrier (BBB)-a functional and structural barrier separating the intravascular and neuropil compartments-characterizes the brain's vascular bed and is essential for normal brain functions. Disruptions to the regional cerebral blood supply, to blood drainage and to BBB properties have been described in most common neurological disorders, but there is a lack of quantitative methods for assessing blood flow dynamics and BBB permeability in small blood vessels under both physiological and pathological conditions. Here, we present a quantitative image analysis approach that allows the characterization of relative changes in the regional cerebral blood flow (rCBF) and BBB properties in small surface cortical vessels. In experiments conducted using the open window technique in rats, a fluorescent tracer was injected into the tail vein, and images of the small vessels at the surface of the cortex were taken using a fast CCD camera. Pixel-based image analysis included registration and characterization of the changes in fluorescent intensity, followed by Cluster analysis. This analysis enabled the characterization of rCBF in small arterioles and venules and changes in BBB permeability. The method was implemented successfully under experimental conditions, including increased rCBF induced by neural stimulation, bile salt-induced BBB breakdown, and photothrombosis-mediated local ischemia. The new approach may be used to Study changes in rCBF, neurovascular coupling and BBB permeability under normal and pathological brain conditions. (C) 2009 Elsevier Inc. All rights reserved.

关键词： Animals Blood-Brain Barrier/pathology Blood-Brain Barrier/physiology Brain/anatomy & histology Brain Ischemia/pathology Brain Ischemia/physiopathology Cerebral Arteries/anatomy & histology Cerebral Arteries/physiology Cerebral Cortex/blood supply Cerebral Cortex/physiology Cerebral Veins/anatomy & histology Cerebral Veins/physiology Cerebrovascular Circulation/physiology Fluorescent Dyes image processing, computer-assisted Isoquinolines Male Permeability Rats Rats, Sprague-Dawley

来源：评论

学校读者我要写书评

暂无评论

Visualizing Ribosome Biogenesis: Parallel Assembly Pathways for the 30S Subunit

引用

SCIENCE 2010年第6004期330卷 673-677页

作者： Mulder, Anke M. Yoshioka, Craig Beck, Andrea H. Bunner, Anne E. Milligan, Ronald A. Potter, Clinton S. Carragher, Bridget Williamson, James R. Scripps Res Inst Dept Mol Biol La Jolla CA 92037 USA Scripps Res Inst Dept Chem La Jolla CA 92037 USA Scripps Res Inst Skaggs Inst Chem Biol La Jolla CA 92037 USA Scripps Res Inst Dept Cell Biol La Jolla CA 92037 USA

Ribosomes are self-assembling macromolecular machines that translate DNA into proteins, and an understanding of ribosome biogenesis is central to cellular physiology. Previous studies on the Escherichia coli 30S subunit suggest that ribosome assembly occurs via multiple parallel pathways rather than through a single rate-limiting step, but little mechanistic information is known about this process. Discovery single-particle profiling (DSP), an application of time-resolved electron microscopy, was used to obtain more than 1 million snapshots of assembling 30S subunits, identify and visualize the structures of 14 assembly intermediates, and monitor the population flux of these intermediates over time. DSP results were integrated with mass spectrometry data to construct the first ribosome-assembly mechanism that incorporates binding dependencies, rate constants, and structural characterization of populated intermediates.

关键词： Bacterial Proteins/chemistry Bacterial Proteins/metabolism image processing, computer-assisted Kinetics Mass Spectrometry Microscopy, Electron/methods Models, Molecular Nucleic Acid Conformation Protein Binding Protein Conformation Ribosomal Proteins/chemistry Ribosomal Proteins/metabolism Ribosome Subunits, Small, Bacterial/chemistry Ribosome Subunits, Small, Bacterial/metabolism Ribosome Subunits, Small, Bacterial/ultrastructure RNA, Bacterial/chemistry RNA, Ribosomal/chemistry

来源：评论

学校读者我要写书评

暂无评论

Reduced prefrontal and orbitofrontal gray matter in female adolescents with borderline personality disorder: Is it disorder specific?

引用

NEUROimage 2010年第1期49卷 114-120页

作者： Brunner, Romuald Henze, Romy Parzer, Peter Kramer, Jasmin Feigl, Nina Lutz, Kira Essig, Marco Resch, Franz Stieltjes, Bram Heidelberg Univ Ctr Psychol Med Dept Child & Adolescent Psychiat D-69115 Heidelberg Germany German Canc Res Ctr Dept Radiol D-6900 Heidelberg Germany

There is evidence that adults with borderline personality disorder (BPD) are characterized by abnormalities in frontolimbic brain areas. In this study we aimed to determine whether brain volume alterations already exist in adolescents with BPD. Sixty female right-handed individuals (age range, 14-18 years), 20 with a DSM-IV diagnosis of borderline personality disorder, 20 patients with a DSM-IV defined current psychiatric disorder and 20 healthy control subjects were included. Groups were matched for age and IQ. Using a 3 T MRI scanner, we collected 1 mm axial sections using a three-dimensional sagittal isotropic Magnetization Prepared Rapid Acquisition Gradient Echo (MPRAGE) sequence. images were analyzed using voxel-based morphometry (VBM). Voxel-based analysis revealed that adolescents with BPD showed reduced gray matter in the dorsolateral cortex (DLPFC) bilaterally and in the left orbitofrontal cortex (OFC) relative to healthy control subjects. Adolescent clinical control subjects displayed significantly decreased gray matter volume in the right DLPFC in comparison with healthy control subjects. No significant gray matter differences were detected between the BPD group and the clinical control group. No group differences were found in the limbic system or in any white matter structures. The present study indicates that the early morphological changes in BPD are located in the PFC. However, these changes may not be BPD specific since similar changes were found in the clinical control group. Changes in limbic brain volumes and white matter structures might occur over the course of the illness. (c) 2009 Elsevier Inc. All rights reserved.

关键词： Adolescent Borderline Personality Disorder/pathology Borderline Personality Disorder/psychology Data Interpretation, Statistical Female Functional Laterality/physiology Humans image processing, computer-assisted Limbic System/pathology Magnetic Resonance Imaging Neuropsychological Tests Prefrontal Cortex/pathology Psychiatric Status Rating Scales

来源：评论

学校读者我要写书评

暂无评论

Cell Lineage Reconstruction of Early Zebrafish Embryos Using Label-Free Nonlinear Microscopy

引用

SCIENCE 2010年第5994期329卷 967-971页

作者： Olivier, Nicolas Luengo-Oroz, Miguel A. Duloquin, Louise Faure, Emmanuel Savy, Thierry Veilleux, Israel Solinas, Xavier Debarre, Delphine Bourgine, Paul Santos, Andres Peyrieras, Nadine Beaurepaire, Emmanuel CNRS Inst Neurobiol Alfred Fessard Gif Sur Yvette France Ecole Polytech CNRS INSERM Lab Opt & Biosci F-91128 Palaiseau France Univ Politecn Madrid Madrid Spain CIBER Biomed Res Ctr BBN Madrid Spain Ecole Polytech CNRS Ctr Rech Epistemol Appl F-75230 Paris France Reseau Natl Syst Complexes Paris France Inst Syst Complexes Paris Ile de France Paris France

Quantifying cell behaviors in animal early embryogenesis remains a challenging issue requiring in toto imaging and automated image analysis. We designed a framework for imaging and reconstructing unstained whole zebrafish embryos for their first 10 cell division cycles and report measurements along the cell lineage with micrometer spatial resolution and minute temporal accuracy. Point-scanning multiphoton excitation optimized to preferentially probe the innermost regions of the embryo provided intrinsic signals highlighting all mitotic spindles and cell boundaries. Automated image analysis revealed the phenomenology of cell proliferation. Blastomeres continuously drift out of synchrony. After the 32-cell stage, the cell cycle lengthens according to cell radial position, leading to apparent division waves. Progressive amplification of this process is the rule, contrasting with classical descriptions of abrupt changes in the system dynamics.

关键词： Animals Blastula/cytology Cell Cycle Cell Lineage Embryo, Nonmammalian/cytology image processing, computer-assisted Microscopy/methods Zebrafish/embryology

来源：评论

学校读者我要写书评

暂无评论

The use of a professional graphics editing program for the preoperative planning in deformity correction surgery: A technical note

引用

INJURY-INTERNATIONAL JOURNAL OF THE CARE OF THE INJURED 2010年第6期41卷 660-664页

作者： Shiha, Anis Krettek, Christian Hankemeier, Stefan Liodakis, Emmanouil Kenawey, Mohamed Hannover Med Sch Trauma Dept D-30625 Hannover Germany Sohag Fac Med Dept Orthopaed Surg Sohag 82524 Egypt

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：