References of "Neuroimage"
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See detailAbnormal neural filtering of irrelevant visual information in depression
Desseilles, Martin ULg; Balteau, Evelyne ULg; Sterpenich, Virginie et al

in NeuroImage (2009), 45(Suppl. 1),

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See detailComputational biology — Modeling of primary blast effects on the central nervous system
Moore, David; Jérusalem, Antoine; Nyen, Michelle et al

in NeuroImage (2009), 47(Sup. 2), 10-20

Objectives Recent military conflicts in Iraq and Afghanistan have highlighted the wartime effect of traumatic brain injury. The reason for the prominence of TBI in these particular conflicts as opposed to ... [more ▼]

Objectives Recent military conflicts in Iraq and Afghanistan have highlighted the wartime effect of traumatic brain injury. The reason for the prominence of TBI in these particular conflicts as opposed to others is unclear but may result from the increased survivability of blast due to improvements in body armor. In the military context blunt, ballistic and blast effects may all contribute to CNS injury, however blast in particular, has been suggested as a primary cause of military TBI. While blast effects on some biological tissues, such as the lung, are documented in term of injury thresholds, this is not the case for the CNS. We hypothesized that using bio-fidelic models, allowing for fluid-solid interaction and basic material properties available in the literature, that a blast wave would interact with CNS tissue and cause a possible concussive effect. Methods The blast shockwave on CNS tissue was modeled using a coupled computational fluid-solid dynamic simulation. The model included a complex finite element mesh of the head and intra-cranial contents. The effects of threshold and 50% lethal blast lung injury were compared with concussive impact injury using the full head model allowing know upper and lower bounds of tissue injury to be applied using pulmonary injury as the reference tissue. Results The effects of a 50% lethal dose blast lung injury (LD50) were comparable with concussive impact injury using the DVBIC – MIT full head model. Interpretation CNS blast concussive effects were found to be similar between impact mild TBI and the blast field associated with LD50 lung blast injury sustained without personal protective equipment. With the ubiquitous use of personal protective equipment this suggests that blast concussive effects may more readily occur in personnel due to enhanced survivability in the current conflicts. [less ▲]

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See detailRejection of pulse related artefact (PRA) from continuous electroencephalographic (EEG) time series recorded during functional magnetic resonance imaging (fMRI) using constraint independent component analysis (cICA).
Leclercq, Yves ULg; Balteau, Evelyne ULg; Dang Vu, Thien Thanh ULg et al

in NeuroImage (2009), 44(3), 679-91

Rejection of the pulse related artefact (PRA) from electroencephalographic (EEG) time series recorded simultaneously with fMRI data is difficult, particularly during NREM sleep because of the similarities ... [more ▼]

Rejection of the pulse related artefact (PRA) from electroencephalographic (EEG) time series recorded simultaneously with fMRI data is difficult, particularly during NREM sleep because of the similarities between sleep slow waves and PRA, in both temporal and frequency domains and the need to work with non-averaged data. Here we introduce an algorithm based on constrained independent component analysis (cICA) for PRA removal. This method has several advantages: (1) automatic detection of the components corresponding to the PRA; (2) stability of the solution and (3) computational treatability. Using multichannel EEG recordings obtained in a 3 T MR scanner, with and without concomitant fMRI acquisition, we provide evidence for the sensitivity and specificity of the method in rejecting PRA in various sleep and waking conditions. [less ▲]

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See detailOptimization of blocked designs in fMRI studies
Maus, Bärbel ULg; Van Breukelen, G.J.P; Goebel, R. et al

in NeuroImage (2009), 47(Supplement 1), 125

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See detailNeural correlates mediating the consolidation of visuomotor adapted actions : A study on the role of night sleep versus the passage of daytime
Debas, Karen; Carrier, Julie; Orban, Pierre et al

in NeuroImage (2009), 45(Suppl. 1),

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See detailNeural Correlates of Envisioning Emotional Events in the near and Far Future
D'Argembeau, Arnaud ULg; Xue, Gui; Lu, Zhong-Lin et al

in NeuroImage (2008), 40(1), 398-407

Being able to envision emotional events that might happen in the future has a clear adaptive value. This study addressed the functional neuroanatomy of this process and investigated whether it is ... [more ▼]

Being able to envision emotional events that might happen in the future has a clear adaptive value. This study addressed the functional neuroanatomy of this process and investigated whether it is modulated by temporal distance. Participants imagined positive and negative events pertaining to the near future or far future while their brain activity was measured with fMRI. The results demonstrate that the anterior part of the ventromedial prefrontal cortex (vmPFC) was more active in envisioning emotional events in the far future than in the near future, whereas the caudate nucleus was engaged in envisioning emotional (especially positive) situations in the near future. We argue that the anterior part of the vmPFC might assign emotional values to mental representations of future events that pertain to long-term goals. On the other hand, the caudate might support more concrete simulations of action plans to achieve rewarding situations in the near future. [less ▲]

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See detailVariational Bayesian inversion of the equivalent current dipole model in EEG/MEG
Kiebel, S. J.; Daunizeau, J.; Phillips, Christophe ULg et al

in Neuroimage (2008), 39(2), 728-741

In magneto- and electroencephalography (M/EEG), spatial modelling of sensor data is necessary to make inferences about underlying brain activity. Most source reconstruction techniques belong to one of two ... [more ▼]

In magneto- and electroencephalography (M/EEG), spatial modelling of sensor data is necessary to make inferences about underlying brain activity. Most source reconstruction techniques belong to one of two approaches: point source models, which explain the data with a small number of equivalent current dipoles and distributed source or imaging models, which use thousands of dipoles. Much methodological research has been devoted to developing sophisticated Bayesian source imaging inversion schemes, while dipoles have received less such attention. Dipole models have their advantages; they are often appropriate summaries of evoked responses or helpful first approximations. Here, we propose a variational Bayesian algorithm that enables the fast Bayesian inversion of dipole models. The approach allows for specification of priors on all the model parameters. The posterior distributions can be used to form Bayesian confidence intervals for interesting parameters, like dipole locations. Furthermore, competing models (e.g., models with different numbers of dipoles) can be compared using their evidence or marginal likelihood. Using synthetic data, we found the scheme provides accurate dipole localizations. We illustrate the advantage of our Bayesian scheme, using a multi-subject EEG auditory study, where we compare competing models for the generation of the N100 component. (C) 2007 Elsevier Inc. All rights reserved. [less ▲]

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See detailChronotype-dependent performance modulation according to time of day : a functional neuroimaging approach
Schmidt, Christina; Collette, Fabienne ULg; Sterpenich, Virginie et al

in NeuroImage (2008), 41(Suppl. 1),

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See detailNeural networks for short-term memory for order differentiate high and low proficiency bilinguals
Majerus, Steve ULg; Belayachi, Sanaa ULg; De Smedt, Bert et al

in NeuroImage (2008), 42

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See detailA three-dimensional MRI atlas of the zebra finch brain in stereotaxic coordinates.
Poirier, Colline; Vellema, Michiel; Verhoye, Marleen et al

in NeuroImage (2008), 41(1), 1-6

The neurobiology of birdsong, as a model for human speech, is a fast growing area of research in the neurosciences and involves electrophysiological, histological and more recently magnetic resonance ... [more ▼]

The neurobiology of birdsong, as a model for human speech, is a fast growing area of research in the neurosciences and involves electrophysiological, 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 microm) 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 electrophysiological recordings. [less ▲]

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See detailStriatal Contribution to sleep-dependent motor consolidation
Debas, Karen; Carrier, Julie; Orban, Pierre et al

in NeuroImage (2008), 41(Suppl. 1),

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See detailWhen thoughts become action: An fMRI paradigm to study volitional brain activity in non-communicative brain injured patients
Boly, Mélanie ULg; Coleman, M. R.; Davis, M. H. et al

in NeuroImage (2007), 36(3), 979-992

The assessment of voluntary behavior in non-communicative brain injured patients is often challenging due to the existence of profound motor impairment. In the absence of a full understanding of the ... [more ▼]

The assessment of voluntary behavior in non-communicative brain injured patients is often challenging due to the existence of profound motor impairment. In the absence of a full understanding of the neural correlates of consciousness, even a normal activation in response to passive sensory stimulation cannot be considered as proof of the presence of awareness in these patients. In contrast, predicted activation in response to the instruction to perform a mental imagery task would provide evidence of voluntary task-dependent brain activity, and hence of consciousness, in non-communicative patients. However, no data yet exist to indicate which imagery instructions would yield reliable single subject activation. The aim of the present study was to establish such a paradigm in healthy volunteers. Two exploratory experiments evaluated the reproducibility of individual brain activation elicited by four distinct mental imagery tasks. The two most robust mental imagery tasks were found to be spatial navigation and motor imagery. In a third experiment, where these two tasks were directly compared, differentiation of each task from one another and from rest periods was assessed blindly using a priori criteria and was correct for every volunteer. The spatial navigation and motor imagery tasks described here permit the identification of volitional brain activation at the single subject level, without a motor response. Volunteer as well as patient data [Owen, A. M., Coleman, M.R., Boly, M., Davis, M.H., Laureys, S., Pickard J.D., 2006. Detecting awareness in the vegetative state. Science 313, 1402] strongly suggest that this' paradigm may provide a method for assessing the presence of volitional brain activity, and thus of consciousness, in non-communicative brain-injured patients. (c) 2007 Elsevier Inc. All rights reserved. [less ▲]

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See detailShort-term memory and the left intraparietal sulcus: Focus of attention? Further evidence from a face short-term memory paradigm
Majerus, Steve ULg; Bastin, Christine ULg; Poncelet, Martine ULg et al

in NeuroImage (2007), 35(1), 353-367

This study explored the validity of an attentional account for the involvement of the left intraparietal sulcus (IPS) in visual STM tasks. This account considers that during STM tasks, the IPS acts as an ... [more ▼]

This study explored the validity of an attentional account for the involvement of the left intraparietal sulcus (IPS) in visual STM tasks. This account considers that during STM tasks, the IPS acts as an attentional modulator, maintaining activation in long-term memory networks that underlie the initial perception and processing of the specific information to be retained. In a recognition STM paradigm, we presented sequences of unfamiliar faces and instructed the participants to remember different types of information: either the identity of the faces or their order of presentation. We hypothesized that, if the left IPS acts as an attentional modulator, it should be active in both conditions, but connected to different neural networks specialized in serial order or face identity processing. Our results showed that the left IPS was activated during both order and identity encoding conditions, but for different reasons. During order encoding, the left IPS showed functional connectivity with order processing areas in the right IPS, bilateral premotor and cerebellar cortices, reproducing earlier results obtained in a verbal STM experiment. During identity encoding, the left IPS showed preferential functional connectivity with right temporal, inferior parietal and medial frontal areas involved in detailed face processing. These results not only support an attentional account of left IPS involvement in visual STM, but given their similarity with previous results obtained for a verbal STM task, they further highlight the importance of the left IPS as an attentional modulator in a variety of STM tasks. [less ▲]

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See detailIn vivo MR imaging of the seasonal volumetric and functional plasticity of song control nuclei in relation to song output in a female songbird
Van Meir, V.; Pavlova, D.; Verhoye, M. et al

in Neuroimage (2006), 31(3), 981-992

In temperate zone songbird species, seasonal plasticity in the morphological and functional state of brain regions involved in song production occurs in association with seasonal changes in song output ... [more ▼]

In temperate zone songbird species, seasonal plasticity in the morphological and functional state of brain regions involved in song production occurs in association with seasonal changes in song output. Following MHCl2-injections in HVC (used as proper name) of female starlings, in vivo tract-tracing by Manganese Enhanced-Magnetic Resonance Imaging (ME-MRI) provided repeated measures of the volume of two HVC targets, the nucleus robustus arcopallii (RA) and area X, along with measures of the activity of the caudal motor pathway and rostral basal-ganglia pathway that control singing. Mn2+- labeling (volume labeled and signal intensity) of both nuclei was dramatically reduced in July (post-breeding season) when birds did not sing, compared to March (breeding season) when birds produced song. Seasonal changes in telencephalon volume did not exceed 4% and were not significant but were surprisingly correlated with individual measures of song rate and song bout length. Although individual song rates were variable in March, all MnCl2-injections led to a reliable labeling of area X and RA. In July, delineation of area X was only possible in two birds and RA could be delineated in 50% of the population; its volume had decreased by 46% as compared to March. The birds in which RA could be delineated in July had in March a higher activity of the HVC to area X projection as reflected by the total amount of Mn2+ accumulated in area X, which suggests unexpected relationships between the two types of HVC projection neurons. (c) 2006 Elsevier Inc. All rights reserved. [less ▲]

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See detailMEG source localization under multiple constraints: An extended Bayesian framework
Mattout, J.; Phillips, Christophe ULg; Penny, W. D. et al

in Neuroimage (2006), 30(3), 753-767

To use Electroencephalography (EEG) and Magnetoencephalography (MEG) as functional brain 3D imaging techniques, identifiable distributed source models are required. The reconstruction of EEG/MEG sources ... [more ▼]

To use Electroencephalography (EEG) and Magnetoencephalography (MEG) as functional brain 3D imaging techniques, identifiable distributed source models are required. The reconstruction of EEG/MEG sources rests on inverting these models and is ill-posed because the solution does not depend continuously on the data and there is no unique solution in the absence of prior in formation or constraints. We have described a general framework that can account for several priors in a common inverse solution. An empirical Bayesian framework based on hierarchical linear models was proposed for the analysis of functional neuroimaging data [Friston, K., Penny, W, Phillips, C., Kiebel, S., Hinton, G., Ashburner, J., 2002. Classical and BaN inference in neuroitnaging: theory. Neurolmage 16, 465-483] and was evaluated recently in the context of EEG [Phillips, C., Mattout, J., Rugg, M.D., Maquet, P., Friston, K., 2005. An empirical Bayesian solution to the source reconstruction problem in EEG. Neurolmage 24, 997-1011]. The approach consists of estimating the expected source distribution and its conditional variance that is constrained by an empirically determined mixture of prior variance components. Estimation uses Expectation-Maximization (EM) to give the Restricted Maximum Likelihood (ReML) estimate of the variance components (in terms of hyperparameters) and the Maximum A Posteriori (MAP) estimate of the source parameters. In this paper, we extend the framework to compare different combinations of priors, using a second level of inference based on Bayesian model selection. Using Monte- Carlo simulations, ReML is first compared to a classic Weighted Minimum Norm (WMN) solution under a single constraint. Then, the ReML estimates are evaluated using various combinations of priors. Both standard criterion and ROC-based measures were used to assess localization and detection performance. The empirical Bayes approach proved useful as: (1) ReML was significantly better than WMN for single priors; (2) valid location priors improved ReML source localization; (3) invalid location priors did not significantly impair performance. Finally, we show how model selection, using the log-evidence, can be used to select file best combination of priors. This enables a global strategy for multiple prior-based regularization of the MEG/EEG source reconstruction. (c) 2005 Elsevier Inc. All rights reserved. [less ▲]

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See detailDecomposition of metabolic brain clusters in the frontal variant of frontotemporal dementia
Salmon, Eric ULg; Kerrouche, Nacer; Herholz, Karl et al

in NeuroImage (2006), 30(3), 871-878

Previous studies that measured brain activity in frontotemporal dementia (FTD) used univariate analyses, examining each region of interest separately. We explored in a multicenter European research ... [more ▼]

Previous studies that measured brain activity in frontotemporal dementia (FTD) used univariate analyses, examining each region of interest separately. We explored in a multicenter European research program the principal brain clusters characterized by a common variability in cerebral metabolism in FTD. Seventy patients with frontal variant (fv) FTD were selected according to international clinical recommendations; principal component analysis (PCA) was performed on FDG-PET metabolic images, looking for covariance clusters in this large population. A first metabolic cluster included most of the lateral and medial prefrontal cortex, bilaterally; PC1 scores correlated with performances on memory and executive neuropsychological tasks. Moreover, FDG-PET images in fv-FTD were further characterized by a metabolic covariance in two clusters comprising the subcallosal medial frontal region, the temporal pole, medial temporal structures and the striatum, separately in the left and in the right hemisphere. The study provides original data-driven arguments for metabolic involvement of separate brain clusters in the rostral limbic system, corresponding to pathological poles differentially affected in each FTD patient. [less ▲]

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See detailNeural correlates of counting of sequential sensory and motor events in the human brain.
Kansaku, Kenji; Johnson, Ari; Grillon, Marie-Laure et al

in NeuroImage (2006), 31(2), 649-60

Little is known about the ability to enumerate small numbers of successive stimuli and movements. It is possible that there exist neural substrates that are consistently recruited both to count sensory ... [more ▼]

Little is known about the ability to enumerate small numbers of successive stimuli and movements. It is possible that there exist neural substrates that are consistently recruited both to count sensory stimuli from different modalities and for counting movements executed by different effectors. Here, we identify a network of areas that was involved in enumerating small numbers of auditory, visual, and somatosensory stimuli, and in enumerating sequential movements of hands and feet, in the bilateral premotor cortex, presupplementary motor area, posterior temporal cortex, and thalamus. The most significant consistent activation across sensory and motor counting conditions was found in the lateral premotor cortex. Lateral premotor activation was not dependent on movement preparation, stimulus presentation timing, or number word verbalization. Movement counting, but not sensory counting, activated the anterior parietal cortex. This anterior parietal area may correspond to an area recruited for movement counting identified by recent single-neuron studies in monkeys. These results suggest that overlapping but not identical networks of areas are involved in counting sequences of sensory stimuli and sequences of movements in the human brain. [less ▲]

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See detailHippocampal response at training promotes insight after sleep
Darsaud, Annabelle; Balteau, Evelyne ULg; Desseilles, Martin ULg et al

in NeuroImage (2006), 31(Suppl. 1),

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See detailA prominent role for amygdaloid complexes in the Variability in Heart Rate (VHR) during Rapid Eye Movement (REM) sleep relative to wakefulness.
Desseilles, Martin ULg; Dang Vu, Thien Thanh ULg; Laureys, Steven ULg et al

in NeuroImage (2006), 32(3), 1008-1015

Rapid eye movement sleep (REMS) is associated with intense neuronal activity, rapid eye movements, muscular atonia and dreaming. Another important feature in REMS is the instability in autonomic ... [more ▼]

Rapid eye movement sleep (REMS) is associated with intense neuronal activity, rapid eye movements, muscular atonia and dreaming. Another important feature in REMS is the instability in autonomic, especially in cardiovascular regulation. The neural mechanisms underpinning the variability in heart rate (VHR) during REMS are not known in detail, especially in humans. During wakefulness, the right insula has frequently been reported as involved in cardiovascular regulation but this might not be the case during REMS. We aimed at characterizing the neural correlates of VHR during REMS as compared to wakefulness and to slow wave sleep (SWS), the other main component of human sleep, in normal young adults, based on the statistical analysis of a set of (H2O)-O-15 positron emission tomography (PET) sleep data acquired during SWS, REMS and wakefulness. The results showed that VHR correlated more tightly during REMS than during wakefulness with the rCBF in the right amygdaloid complex. Moreover, we assessed whether functional relationships between amygdala and any brain area changed depending the state of vigilance. Only the activity within in the insula was found to covary with the amygdala, significantly more tightly during wakefulness than during REMS in relation to the VHR. The functional connectivity between the amygdala and the insular cortex, two brain areas involved in cardiovascular regulation, differs significantly in REMS as compared to wakefulness. This suggests a functional reorganization of central cardiovascular regulation during REMS. (c) 2006 Elsevier Inc. All rights reserved. [less ▲]

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