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The roles of "face" and "non-face" areas during individual face perception: Evidence by fMRI adaptation in a brain-damaged prosopagnosic patient

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NEUROimage 2008年第1期40卷 318-332页

作者： Dricot, Laurence Sorger, Bettina Schiltz, Christine Goebel, Rainer Rossion, Bruno Univ Louvain Dept Neurophysiol Louvain Belgium Maastricht Univ Dept Cognit Neurosci Maastricht Netherlands Maastricht Brain Imaging Ctr Maastricht Netherlands Univ Louvain Dept Cognit Dev Louvain Belgium

Two regions in the human occipito-temporal cortex respond preferentially to faces: 'the fusiform face area' ('FFA') and the 'occipital face area' ('OFA'). Whether these areas have a dominant or exclusive role in face perception, or if sub-maximal responses in other visual areas such as the lateral occipital complex (LOC) are also involved, is currently debated. To shed light on this issue, we tested normal participants and PS, a well-known brain-damaged patient presenting a face-selective perception deficit (prosopagnosia) [Rossion, B., Caldara, R., Seghier, M., Schuller, A. M., Lazeyras, F., Mayer, E. (2003). A network of occipito-temporal face-sensitive areas besides the right middle fusiform gyros is necessary for normal face processing. Brain 126 2381-2395.], with functional magnetic resonance imaging (fMRI). Of particular interest, the right hemisphere lesion of the patient PS encompasses the 'OFA' but preserves the 'FFA' and LOC [Sorger, B., Goebel, R., Schiltz, C., Rossion, B. (2007). Understanding the functional neuroanatomy of acquired prosopagnosia. Neuroimage 35, 836-852.]. Using fMRI-adaptation, we found a dissociation between the coding of individual exemplars in the structurally intact 'FFA', which was impaired for faces but preserved for objects in the patient PS's brain. Most importantly, a larger response to different faces than repeated faces was found in the ventral part of the LOC both for normals and the patient, next to the right hemisphere lesion. Thus, following prosopagnosia, areas that do not respond preferentially to faces such as the ventral part of the LOC (vLOC) may still be recruited for compensatory or residual individual face perception. Overall, these observations indicate that several highlevel visual areas in the human brain contribute to individual face perception. However, a subset of these areas in the right hemisphere, those responding preferentially to faces ('FFA' and 'OFA'), appear to be critical for this function. (c) 2007

关键词： Adult Cerebral Cortex/pathology Cerebral Cortex/physiopathology Data Interpretation, Statistical Discrimination (Psychology)/physiology Face Female Head Injuries, Closed/pathology Head Injuries, Closed/pathology Head Injuries, Closed/physiopathology Head Injuries, Closed/physiopathology Head Injuries, Closed/psychology Head Injuries, Closed/psychology Humans image processing, computer-assisted Magnetic Resonance Imaging Male Middle Aged Occipital Lobe/pathology Occipital Lobe/physiopathology Prosopagnosia/pathology Prosopagnosia/physiopathology Prosopagnosia/psychology Visual Perception/physiology

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DNA poised for release in bacteriophage φ29

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STRUCTURE 2008年第6期16卷 935-943页

作者： Tang, Jinghua Olson, Norman Jardine, Paul J. Grimes, Shelley Anderson, Dwight L. Baker, Timothy S. Univ Minnesota Dept Diagnost & Biol Sci Minneapolis MN 55455 USA Univ Minnesota Inst Mol Virol Minneapolis MN 55455 USA Univ Calif San Diego Dept Chem & Biochem La Jolla CA 92093 USA Univ Minnesota Dept Microbiol Minneapolis MN 55455 USA Univ Calif San Diego Div Biol Sci La Jolla CA 92093 USA

We present here the first asymmetric, three-dimensional reconstruction of a tailed dsDNA virus, the mature bacteriophage phi 29, at subnanometer resolution. This structure reveals the rich detail of the asymmetric interactions and conformational dynamics of the phi 29 protein and DNA components, and provides novel insight into the mechanics of virus assembly' For example, the dodecameric head-tail connector protein undergoes significant rearrangement upon assembly into the virion. Specific interactions occur between the tightly packed dsDNA and the proteins of the head and tail. Of particular interest and novelty, an similar to 60 angstrom diameter toroid of dsDNA was observed in the connector-lower collar cavity. The extreme deformation that occurs over a small stretch of DNA is likely a consequence of the high pressure of the packaged genome. This toroid structure may help retain the DNA inside the capsid prior to its injection into the bacterial host.

关键词： Bacillus Phages/genetics Bacillus Phages/physiology Bacillus Phages/ultrastructure Capsid Proteins/chemistry Capsid Proteins/ultrastructure DNA, Viral/chemistry DNA, Viral/ultrastructure image processing, computer-assisted Models, Molecular Nucleic Acid Conformation Protein Conformation Virion/chemistry Virion/ultrastructure Virus Assembly

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Normal database of dopaminergic neurotransmission system in human brain measured by positron emission tomography

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NEUROimage 2008年第2期39卷 555-565页

作者： Ito, Hiroshi Takahashi, Hidehiko Arakawa, Ryosuke Takano, Harumasa Suhara, Tetsuya Natl Inst Radiol Sci Mol Imaging Ctr Mol Neuroimaging Grp Clin Neuroimaging Team Chiba 2638555 Japan

The central dopaminergic system is of interest in the pathophysiology of schizophrenia and other neuropsychiatric disorders. Both pre- and postsynaptic dopaminergic functions can be estimated by positron emission tomography (PET) with different radiotracers. However, an integrated database of both pre- and postsynaptic dopaminergic neurotransmission components including receptors, transporter, and endogenous neurotransmitter synthesis has not yet been reported. In the present study, we constructed a normal database for the pre- and postsynaptic dopaminergic functions in the living human brain using PET. To measure striatal and extrastriatal dopamine D-1 and D-2 receptor bindings, dopamine transporter binding, and endogenous dopamine synthesis rate, PET scans were performed on healthy men after intravenous injection of [C-11]SCH23390, [C-11]raclopride, [C-11]FLB457, [C-11]PE21, or L-[beta-C-11]DOPA. All PET images were anatomically standardized using SPM2, and a database was built for each radiotracer. Gray matter images were segmented and extracted from all anatomically standardized magnetic resonance images using SPM2, and they were used for partial volume correction. These databases allow the comparison of regional distributions of striatal and extrastriatal dopamine D, and D2 receptors, dopamine transporter, and endogenous dopamine synthesis capability. These distributions were in good agreement with those from human postmortem studies. This database can be used in various researches to understand the physiology of dopaminergic functions in the living human brain. This database could also be used to investigate regional abnormalities of dopaminergic neurotransmission in neuropsychiatric disorders. (C) 2007 Elsevier Inc. All rights reserved.

关键词： Adult Algorithms Benzazepines/diagnostic use Brain/physiology Brain/radionuclide imaging Brain Chemistry/physiology Data Interpretation, Statistical Databases, Factual Dopamine/biosynthesis Dopamine/physiology Dopamine Antagonists/diagnostic use Dopamine Plasma Membrane Transport Proteins/metabolism Humans image processing, computer-assisted Kinetics Magnetic Resonance Imaging Male Nortropanes/diagnostic use Positron-Emission Tomography Protein Binding Pyrrolidines/diagnostic use Raclopride/diagnostic use Raclopride/diagnostic use Radiopharmaceuticals/diagnostic use Radiopharmaceuticals/diagnostic use Receptors, Dopamine D1/metabolism Receptors, Dopamine D2/metabolism Receptors, Presynaptic/physiology Reference Values Salicylamides/diagnostic use Synaptic Transmission/physiology

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I learned from what you did:: Retrieving visuornotor associations learned by observation

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NEUROimage 2008年第3期42卷 1207-1213页

作者： Monfardini, Elisabetta Brovelli, Andrea Boussaoud, Driss Takerkart, Sylvain Wicker, Bruno CNRS F-13402 Marseille France Aix Marseille Univ Mediterranean Inst Cognit Neurosci UMR 6193 F-13402 Marseille France

Observational learning allows individuals to acquire knowledge without incurring in the costs and risks of discovering and testing. The neural mechanisms mediating the retrieval of rules learned by observation are currently unknown. To explore this fundamental cognitive ability, we compared the brain responses when retrieving visuomotor associations learned either by observation or by individual learning. To do so, we asked eleven adults to learn two sets of arbitrary visuomotor associations: one set was learned through the observation of an expert actor while the other was learned by trial and error. During fMRI scanning, subjects were requested to retrieve the visuomotor associations previously learned under the two modalities. The conjunction analysis between the two learning conditions revealed a common brain network that included the ventral and dorsal lateral prefrontal cortices, the superior parietal lobe and the pre-SMA. This suggests the existence of a mirror-like system responsible for the storage of rules learned either by trial and error or by observation of others' actions. In addition, the pars triangularis in the right prefrontal cortex (BA45) was found to be selective for rules learned by observation. This suggests a preferential role of this area in the storage of rules learned in a social context. (c) 2008 Elsevier Inc. All rights reserved.

关键词： Adult Brain/physiology Brain Mapping Brain Mapping Female Humans image processing, computer-assisted Learning/physiology Magnetic Resonance Imaging Male Photic Stimulation Psychomotor Performance/physiology

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Analysis of laminar activity in normal and injured rat spinal cord by manganese enhanced MRI

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NEUROimage 2008年第4期40卷 1542-1551页

作者： Bonny, Jean-Marie Mailly, Philippe Renou, Jean-Pierre Orsal, Didier BenMoussa, Abdelatif Stettler, Olivier INRA STIM UR370 QuaPA F-63122 St Genes Champanelle France Univ Paris 06 CNRS UMR 7101 F-75005 Paris France

The present study provides an account of a sensitive and rapid experimental approach for MRI visualization and analysis of spinal cord (SC) laminar activity in normal and injured animals. This approach is based upon neuronal activity-dependant manganese (Mn) uptake after focal SC injection of MnCl2, and subsequent ex-vivo magnetic resonance imaging ( MRI) of activated SC pathways. The method was designed as an alternative to time-intensive histochemical and behavioral approaches typically used for analysis of spinal cord injury (SCI) and our results provide both anatomical and functional insights. We show that ex vivo imaging can determine layer-specific activity over an extended region of the rat SC. In addition, we demonstrate that the Mn concentration profile along the SC axis accurately reflects the type of SC injury. The approach is flexible since MRI analysis can be done immediately after animal sacrifice, or alternatively several days later, without a loss of sensitivity. Moreover, the integrity and functional state of SC circuitry can be analyzed in less than 1 h whereas several days and weeks are necessary to perform classical histochemical and behavioral analysis. Thus our method can be used for precise assessment of the extent of dysfunction or change in SC disorders and may facilitate the screening of molecules with therapeutic potential after SC injury. (c) 2008 Elsevier Inc. All rights reserved.

关键词： Animals Chlorides/diagnostic use Chlorides/pharmacokinetics Contrast Media Contrast Media Female image processing, computer-assisted Longitudinal Studies Magnetic Resonance Imaging Manganese Compounds/diagnostic use Manganese Compounds/pharmacokinetics Rats Rats, Wistar Spinal Cord Injuries/pathology Spinal Cord Injuries/pathology

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A three-dimensional MRI atlas of the zebra finch brain in stereotaxic coordinates

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NEUROimage 2008年第1期41卷 1-6页

作者： Poirier, Colline Vellema, Michiel Verhoye, Marleen Van Meir, Vincent Wild, J. Martin Balthazart, Jacques Van Der Linden, Annemie Univ Antwerp Bioimaging Lab Dept Biomed Sci B-2020 Antwerp Belgium Max Planck Inst Ornithol Dept Behav Neurobiol D-82319 Seewiesen Germany Univ Antwerp Vis Lab B-2020 Antwerp Belgium Univ Auckland Dept Anat Avian Neurobiol Lab Auckland 92019 New Zealand Univ Liege Ctr Cellular & Mol Neurobiol Res Unit Behav Neuroendocrinol B-4000 Liege Belgium

The neurobiology of birdsong, as a model for human speech, is a fast growing area of research in the neurosciences and involves electro-physiological, histological and more recently magnetic resonance imaging (MRI) approaches. Many of these studies require the identification and localization of different brain areas (nuclei) involved in the sensory and motor control of song. Until now, the only published atlases of songbird brains consisted in drawings based on histological slices of the canary and of the zebra finch brain. Taking advantage of high-magnetic field (7 Tesla) MRI technique, we present the first high-resolution (80 x 160 x 160 mu m) 3-D digital atlas in stereotaxic coordinates of a male zebra finch brain, the most widely used species in the study of birdsong neurobiology. image quality allowed us to discern most of the song control, auditory and visual nuclei. The atlas can be freely downloaded from our Web site and can be interactively explored with MRIcro. This zebra finch MRI atlas should become a very useful tool for neuroscientists working on birdsong, especially for co-registrating MRI data but also for determining accurately the optimal coordinates and angular approach for injections or electro-physiological recordings. (c) 2008 Elsevier Inc. All rights reserved.

关键词： Animals Brain/anatomy & histology Data Interpretation, Statistical Finches/anatomy & histology image processing, computer-assisted Magnetic Resonance Imaging Male Stereotaxic Techniques Tomography, X-Ray Computed

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Local dendritic activity sets release probability at hippocampal synapses

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NEURON 2008年第3期59卷 475-485页

作者： Branco, Tiago Staras, Kevin Darcy, Kevin J. Goda, Yukiko UCL MRC Lab Mol Cell Biol London WC1E 6BT England UCL Cell Biol Unit London WC1E 6BT England UCL Dept Neurosci Physiol & Pharmacol London WC1E 6BT England

The arrival of an action potential at a synapse triggers neurotransmitter release with a limited probability, p,. Although p, is a fundamental parameter in defining synaptic efficacy, it is not uniform across all synapses, and the mechanisms by which a given synapse sets its basal release probability are unknown. By measuring p, at single presynaptic terminals in connected pairs of hippocampal neurons, we show that neighboring synapses on the same dendritic branch have very similar release probabilities, and p, is negatively correlated with the number of synapses on the branch. Increasing dendritic depolarization elicits a homeostatic decrease in p, and equalizing activity in the dendrite significantly reduces its variability. Our results indicate that local dendritic activity is the major determinant of basal release probability, and we suggest that this feedback regulation might be required to maintain synapses in their operational range.

关键词： Action Potentials/physiology Animals Animals, Newborn Cells, Cultured Dendrites/metabolism Dendrites/ultrastructure Electric Stimulation/methods Excitatory Postsynaptic Potentials/physiology Excitatory Postsynaptic Potentials/radiation effects Hippocampus/cytology image processing, computer-assisted Microscopy, Electron, Transmission Models, Neurological Neurons/cytology Patch-Clamp Techniques Patch-Clamp Techniques Probability Pyridinium Compounds/metabolism Quaternary Ammonium Compounds/metabolism Quaternary Ammonium Compounds/metabolism Rats Synapses/metabolism Synapses/ultrastructure

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A method for functional network connectivity among spatially independent resting-state components in schizophrenia

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NEUROimage 2008年第4期39卷 1666-1681页

作者： Jafri, Madiha J. Pearlson, Godfrey D. Stevens, Michael Calhoun, Vince D. MIND Inst Albuquerque NM 87131 USA Inst Living Olin Neuropsychiat Res Ctr Hartford CT 06106 USA Yale Univ Sch Med Dept Psychiat New Haven CT 06520 USA Univ New Mexico Dept ECE Albuquerque NM 87131 USA

Functional connectivity of the brain has been studied by analyzing correlation differences in time courses among seed voxels or regions with other voxels of the brain in healthy individuals as well as in patients with brain disorders. The spatial extent of strongly temporally coherent brain regions co-activated during rest has also been examined using independent component analysis (ICA). However, the weaker temporal relationships among ICA component time courses, which we operationally define as a measure of functional network connectivity (FNC), have not yet been studied. In this study, we propose an approach for evaluating FNC and apply it to functional magnetic resonance imaging (fMRI) data collected from persons with schizophrenia and healthy controls. We examined the connectivity and latency among ICA component time courses to test the hypothesis that patients with schizophrenia would show increased functional connectivity and increased lag among resting state networks compared to controls. Resting state fMRI data were collected and the interrelationships among seven selected resting state networks (identified using group ICA) were evaluated by correlating each subject's ICA time courses with one another. Patients showed higher correlation than controls among most of the dominant resting state networks. Patients also had slightly more variability in functional connectivity than controls. We present a novel approach for quantifying functional connectivity among brain networks identified with spatial ICA. Significant differences between patient and control connectivity in different networks were revealed possibly reflecting deficiencies in cortical processing in patients. (C) 2007 Elsevier Inc. All rights reserved.

关键词： Adult Algorithms Cerebrovascular Circulation/physiology Female Humans image processing, computer-assisted Magnetic Resonance Imaging Male Middle Aged Nerve Net/physiopathology Neural Pathways/physiopathology Principal Component Analysis Reproducibility of Results Schizophrenia/physiopathology

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Persistence of DNA threads in human anaphase cells suggests late completion of sister chromatid decatenation

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CHROMOSOMA 2008年第2期117卷 123-135页

作者： Wang, Lily Hui-Ching Schwarzbraun, Thomas Speicher, Michael R. Nigg, Erich A. Max Planck Inst Biochem Dept Cell Biol D-82152 Martinsried Germany Med Univ Graz Inst Human Genet Graz Austria

PICH (Plk1-interacting checkpoint helicase) was recently identified as an essential component of the spindle assembly checkpoint and shown to localize to kinetochores, inner centromeres, and thin threads connecting separating chromosomes even during anaphase. In this paper, we have used immuno-fiber fluorescence in situ hybridization and chromatin-immunoprecipitation to demonstrate that PICH associates with centromeric chromatin during anaphase. Furthermore, by careful analysis of PICH-positive anaphase threads through FISH as well as bromo-deoxyurdine and CREST labeling, we strengthen the evidence that these threads comprise mainly alphoid centromere deoxyribonucleic acid. Finally, by timing the addition of ICRF-193 (a specific inhibitor of topoisomerase-II alpha) to cells synchronized in anaphase, we demonstrate that topoisomerase activity is required specifically to resolve PICH-positive threads during anaphase (as opposed to being required to prevent the formation of such threads during earlier cell cycle stages). These data indicate that PICH associates with centromeres during anaphase and that most PICH-positive threads evolve from inner centromeres as these stretch in response to tension. Moreover, they show that topoisomerase activity is required during anaphase for the resolution of PICH-positive threads, implying that the complete separation of sister chromatids occurs later than previously assumed.

关键词： Anaphase Centromere/ultrastructure Centrosome/ultrastructure Centrosome/ultrastructure Chromatids/ultrastructure Chromatin/metabolism Chromosome Segregation DNA Helicases/genetics DNA Topoisomerases, Type II/metabolism Hela Cells Humans image processing, computer-assisted In Situ Hybridization, Fluorescence In Situ Hybridization, Fluorescence Kinetochores Microscopy, Fluorescence Nucleic Acid Hybridization

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Network injury to pulvinar with neonatal arterial ischemic stroke

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NEUROimage 2008年第4期39卷 1850-1857页

作者： Govaert, Paul Zingman, Alissa Jung, Youn Hoa Dudink, Jeroen Swarte, Renate Zecic, Alexandra Meerssehaut, Valerie van Engelen, Susanne Lequin, Maarten Sofia Childrens Hosp Erasmus MC Rotterdam Neonatal Intens Care Unit NL-3015 GJ Rotterdam Netherlands Univ Maryland Sch Med Baltimore MD 21201 USA Georgetown Univ Washington DC USA Ghent Univ Hosp Neonatal Intens Care Unit Ghent Belgium

The purpose of this study is to establish that newborn stroke involving extensive parts of cerebral cortex immediately leads to secondary network injury in pulvinar. Seven term infants with cortical stroke presented with hypersignal in pulvinar on DWI. Stroke types included: complete MCA stroke (n=4);PCA stroke, ICA stroke and multiple artery stroke (1 each). Age range at scanning was between day 2 and 6 after birth (except for 1 infant scanned within 7 days of acute presentation during ECMO). ADC values in secondarily injured pulvinar were significantly higher than in the area with primary (sub)cortical injury (all patients scanned with identical MR image acquisition). In the absence of asphyxia and because pulvinar is outside of the primary area of infarction, we conclude that there are suggestions from imaging for acute secondary injury to pulvinar following primary damage of their cortical targets and/or connecting axons. Acute secondary injury is probably due to excitotoxicity and deafferentiation. The relevance of network injury for prognosis and the impact of early treatment on it have yet to be studied, in stroke but also in other acute perinatal brain disorders. (c) 2007 Elsevier Inc. All rights reserved.

关键词： Brain Ischemia/complications Brain Ischemia/congenital Brain Ischemia/pathology Cerebral Cortex/pathology Female Humans image processing, computer-assisted Infant, Newborn Magnetic Resonance Imaging Male Nerve Net/pathology Prognosis Stroke/congenital Stroke/etiology Stroke/pathology Thalamus/pathology

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