Abstract:
:Quantitative mapping of the longitudinal relaxation rate (R1=1/T1) in the human brain enables the investigation of tissue microstructure and macroscopic morphology which are becoming increasingly important for clinical and neuroimaging applications. R1 maps are now commonly estimated from two fast high-resolution 3D FLASH acquisitions with variable excitation flip angles, because this approach is fast and does not rely on special acquisition techniques. However, these R1 maps need to be corrected for bias due to RF transmit field (B1(+)) inhomogeneities, requiring additional B1(+) mapping which is usually time consuming and difficult to implement. We propose a technique that simultaneously estimates the B1(+) inhomogeneities and R1 values from the uncorrected R1 maps in the human brain without need for B1(+) mapping. It employs a probabilistic framework for unified segmentation based correction of R1 maps for B1(+) inhomogeneities (UNICORT). The framework incorporates a physically informed generative model of smooth B1(+) inhomogeneities and their multiplicative effect on R1 estimates. Extensive cross-validation with the established standard using measured B1(+) maps shows that UNICORT yields accurate B1(+) and R1 maps with a mean deviation from the standard of less than 4.3% and 5%, respectively. The results of different groups of subjects with a wide age range and different levels of atypical brain anatomy further suggest that the method is robust and generalizes well to wider populations. UNICORT is easy to apply, as it is computationally efficient and its basic framework is implemented as part of the tissue segmentation in SPM8.
journal_name
Neuroimagejournal_title
NeuroImageauthors
Weiskopf N,Lutti A,Helms G,Novak M,Ashburner J,Hutton Cdoi
10.1016/j.neuroimage.2010.10.023subject
Has Abstractpub_date
2011-02-01 00:00:00pages
2116-24issue
3eissn
1053-8119issn
1095-9572pii
S1053-8119(10)01315-7journal_volume
54pub_type
杂志文章相关文献
NEUROIMAGE文献大全abstract::The large amount of imaging data collected in several ongoing multi-center studies requires automated methods to delineate brain structures of interest. We have previously reported on using artificial neural networks (ANN) to define subcortical brain structures. Here we present several automated segmentation methods u...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2007.05.063
更新日期:2008-01-01 00:00:00
abstract::Human contrast discrimination performance is limited by transduction nonlinearities and variability of the neural representation (noise). Whereas the nonlinearities have been well-characterised, there is less agreement about the specifics of internal noise. Psychophysical models assume that it impacts late in sensory ...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2019.02.049
更新日期:2019-05-01 00:00:00
abstract::We previously introduced a voxel-based, multi-modal application of the partial least square algorithm (MMPLS) to characterize the linkage between patterns in a person's complementary complex datasets without the need to correct for multiple regional comparisons. Here we used it to demonstrate a strong correlation betw...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2012.02.005
更新日期:2012-05-01 00:00:00
abstract::In this work we explore whether the patterns of brain activity associated with thinking about concrete objects are dependent on stimulus presentation format, whether an object is referred to by a written or pictorial form. Multi-voxel pattern analysis methods were applied to brain imaging (fMRI) data to identify the i...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2010.10.042
更新日期:2011-02-01 00:00:00
abstract::Near-infrared spectroscopy (NIRS) has recently been used to measure human motor-cortical activation, enabling the classification of the content of a sensory-motor event such as whether the left or right hand was used. Here, we advance this NIRS application by demonstrating quantitative estimates of multiple sensory-mo...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2009.04.050
更新日期:2009-08-15 00:00:00
abstract::On the basis of anatomical and physiological data obtained on animal models, we recently proposed that neurons in the main visual extrageniculate nuclei complex, the pulvinar, are actively involved in higher-order visual processing. Pulvinar neurons have been shown to integrate the component signals of a plaid pattern...
journal_title:NeuroImage
pub_type: 临床试验,杂志文章
doi:10.1016/j.neuroimage.2005.06.015
更新日期:2005-11-01 00:00:00
abstract::Neuroimaging studies of reading converge to suggest that linguistically elementary stimuli are confined to the activation of bilateral posterior regions, whereas linguistically complex stimuli additionally recruit left hemispheric anterior regions, raising the hypotheses of a gradual bilateral-to-left and a posterior-...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2008.08.008
更新日期:2008-11-15 00:00:00
abstract::Increasing evidence underlines the functional importance of non-phase-locked cortical oscillatory rhythms. Among the different oscillations, alpha (8-12 Hz) has been shown to be modulated by anticipation or attention, suggesting a top-down influence. However, most studies to date have been conducted in the visual moda...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2011.12.034
更新日期:2012-03-01 00:00:00
abstract:BACKGROUND:High sensation-seekers (HSS) pursue novelty even at the cost of self-harm. When challenged, HSS are less anxious, show blunted physiological (cortisol, startle) and neurobiological (prefrontal-limbic) responses, and devalue aversive outcomes. Here, we investigate how these features interact under conditions ...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2014.08.038
更新日期:2014-12-01 00:00:00
abstract::In an effort to examine the functional neuroanatomy of semantic memory, we studied the relative cerebral blood flow of eight healthy young subjects using 15O-water positron emission tomography (PET). Relative to a visual baseline control condition, each of four visual matching-to-sample tasks activated components of t...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1006/nimg.1998.0386
更新日期:1999-01-01 00:00:00
abstract::The association between white matter hyperintensities (WMH) and amyloid accumulation over time in cognitively normal, amyloid-negative elderly people remains largely unexplored. In order to study whether baseline WMH were associated with longitudinal subthreshold amyloid accumulation, 159 cognitively normal participan...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2020.116944
更新日期:2020-09-01 00:00:00
abstract::MR diffusion tensor imaging (DTI) can measure and visualize organization of white matter fibre tracts in vivo. DTI is a relatively new imaging technique, and new tools developed for quantifying fibre tracts require evaluation. The purpose of this study was to compare the reliability of a novel clustering approach with...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2008.12.028
更新日期:2009-04-01 00:00:00
abstract::Understanding the differences between individuals' personality types at a functional brain level is now possible due to recent developments in both functional brain imaging and personality models. The psychobiological model for temperament and character offers one approach to exploring personality. This study uses SPE...
journal_title:NeuroImage
pub_type: 临床试验,杂志文章
doi:10.1016/s1053-8119(03)00171-x
更新日期:2003-07-01 00:00:00
abstract:AIMS:Using functional magnetic resonance imaging (fMRI) we investigated the cortical and subcortical representations during bladder filling and the effect of simultaneous stimulation of the dorsal clitoral nerve on these cortical and subcortical structures. METHODS:After approval of the local ethics committee, 8 healt...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2008.03.006
更新日期:2008-07-01 00:00:00
abstract::We used serial positron emission tomography (PET) to study training-induced brain plasticity after severe hemiparetic stroke. Ten patients were randomized to either task-oriented arm training or to a control group and scanned before and after 22.6 +/- 1.6 days of treatment using passive movements as an activation para...
journal_title:NeuroImage
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1006/nimg.2001.0757
更新日期:2001-06-01 00:00:00
abstract::There is strong interest in investigating both functional connectivity (FC) using functional magnetic resonance imaging (fMRI) and structural connectivity (SC) using diffusion tensor imaging (DTI). There is also emerging evidence of correspondence between functional and structural pathways within many networks (Greici...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2012.05.032
更新日期:2012-09-01 00:00:00
abstract::Brain white matter tissue composition can be quantified using Diffusion Tensor Imaging (DTI) and Magnetization Transfer Imaging (MTI). Fractional Anisotropy (FA), derived from DTI, indexes the integrity, density and organization of axons. Magnetization Transfer Ratio (MTR), derived from MTI, indexes to the presence of...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2011.03.016
更新日期:2011-06-15 00:00:00
abstract::Memory crucially depends on the way information is processed during encoding. Differences in processes during encoding not only lead to differences in memory performance but also rely on different brain networks. Although these assumptions are corroborated by several previous fMRI and ERP studies, little is known abou...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2013.04.121
更新日期:2013-10-01 00:00:00
abstract::Age-related differences in cognitive agility vary greatly between individuals and cognitive functions. This heterogeneity is partly mirrored in individual differences in brain network connectivity as revealed using resting-state functional magnetic resonance imaging (fMRI), suggesting potential imaging biomarkers for ...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2017.01.048
更新日期:2017-03-01 00:00:00
abstract::Small-world organization is known to be a robust and consistent network architecture, and is a hallmark of the structurally and functionally connected human brain. However, it remains unknown if the same organization is present in directed influence brain networks whose connectivity is inferred by the transfer of info...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2010.11.007
更新日期:2011-02-14 00:00:00
abstract::The ε4 allele of apolipoprotein E (apoE, protein; APOE, gene) is the most important genetic risk factor for the development of Alzheimer's disease (AD). Cortical structures in the medial temporal lobe (MTL) are important for memory function and are affected early in AD. Both gray matter (GM) and white matter (WM) stru...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2012.06.072
更新日期:2012-10-15 00:00:00
abstract::Semantic language skills are an integral part of early childhood language development. The semantic association between verbs and nouns constitutes an important building block for the construction of sentences. In this large-scale functional magnetic resonance imaging (fMRI) study, involving 336 subjects between the a...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2009.12.108
更新日期:2010-05-15 00:00:00
abstract::It is well documented that emotionally arousing experiences are better remembered than mundane events. This is thought to occur through hippocampus-amygdala crosstalk during encoding, consolidation, and retrieval. Here we investigated whether emotional events (context) also cause a memory benefit for simultaneously en...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2016.08.069
更新日期:2016-12-01 00:00:00
abstract::We used functional magnetic resonance imaging to examine neuronal activity reflecting the dynamic interplay of external and internal guidance of action. Participants performed a choice reaction time task based on spatial visual cues with their right and left middle and index finger. In a given trial, the cue either fu...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2005.07.014
更新日期:2006-01-01 00:00:00
abstract::Most current functional Magnetic Resonance Imaging (fMRI) decoding analyses rely on statistical summaries of the data resulting from a deconvolution approach: each stimulation event is associated with a brain response. This standard approach leads to simple learning procedures, yet it is ill-suited for decoding events...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2017.08.018
更新日期:2018-10-15 00:00:00
abstract::Multi-echo T(2) relaxation decay data was acquired for 5 preadolescent males (age range 9-12 years). A signal to noise filter appropriate for multi-exponential T(2) analysis was then applied to remove voxels which did not accurately fit the modelled curve. The remaining voxels were designated "highly myelinated" if th...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2008.07.038
更新日期:2008-12-01 00:00:00
abstract::Despite there being an increasing number of installations of ultra high field MR systems (>3T) in clinical environments, no functional patient investigations have yet examined possible benefits for functional diagnostics. Here we performed presurgical localization of the primary motor hand area on 3T and 7T Siemens sc...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2011.05.010
更新日期:2011-08-01 00:00:00
abstract::Delayed acquisition of developmental motor and cognitive milestones is a common clinical expression of many etiological processes. Imaging exams of developmentally delayed children often show no structural brain alterations despite suspicion of brain maturation delay. MRI studies increasingly suggest that white matter...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2004.01.029
更新日期:2004-06-01 00:00:00
abstract::To gain efficiency in performance of a novel complex movement, we must learn to coordinate the action of the pertinent muscle groups. We used functional magnetic resonance imaging (fMRI) to investigate the mechanisms of learning a novel synergic movement in human primary motor cortex (M1). We show for the first time c...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2007.01.009
更新日期:2007-04-15 00:00:00
abstract::A common assumption in the study of brain functional connectivity is that the brain network is stationary. However it is increasingly recognized that the brain organization is prone to variations across the scanning session, fueling the need for dynamic connectivity approaches. One of the main challenges in developing...
journal_title:NeuroImage
pub_type: 杂志文章
doi:10.1016/j.neuroimage.2018.07.045
更新日期:2018-12-01 00:00:00