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Ultra-Fast fMRI Imaging with High-Fidelity Activation Map [chapter]

Neelam Sinha, Manojkumar Saranathan, A. G. Ramakrishnan, Juan Zhou, Jagath C. Rajapakse
2006 Lecture Notes in Computer Science  
Performance evaluation is carried out by comparing activation maps obtained using reconstructed images, against that obtained from the true images.  ...  We observe upto 10dB improvement in PSNR of activation maps.  ...  Reconstruction errors for acceleration factor 5 in (a) y-f map (b) Image series (RMSE) ; (c) Correlation with reference activation map  ... 
doi:10.1007/11893257_40 fatcat:izak77in4zdt3drkpr2bgzsnfq

Erratum zu: Kontrastmittel in der Radiologie

P. Reimer, R. Vosshenrich
2013 Der Radiologe (Berlin. Print)  
Chen G, Wang F, Gore JC et al (2013) Layer-specific BOLD activation in awake monkey V1 revealed by ultra-high spatial resolution functional magnetic resonance imaging.  ...  In MH, Speck O (2012) Highly accelerated PSF- mapping for EPI distortion correction with impro- ved fidelity. MAGMA 25:183-192 5.  ... 
doi:10.1007/s00117-013-2505-6 fatcat:gkydbtfgpjhopf6cj3tc3mjjce

Multi-phase passband balanced SSFP fMRI with 50 ms sampling rate at 7 Tesla enables high precision in resolving 100 ms neuronal events

Zhongwei Chen, Rong Xue, Peng Zhang, Kaibao Sun, Zhentao Zuo, Jing An, Jing Chen, Sheng He, Lin Chen, Danny J.J. Wang
2017 Magnetic Resonance Imaging  
In addition, most of existing ultra-fast fMRI techniques are based on gradient-echo EPI that suffers from the T1 saturation effect with high temporal sampling rate (short TR).  ...  Alternative ultra-fast fMRI techniques include inverse imaging based methods [18] that are analogous to source localization of MEG and EEG.  ... 
doi:10.1016/j.mri.2016.08.013 pmid:27580519 fatcat:27thw7vd4fbencmdxcx2ugesnq

Data-driven optimization and evaluation of 2D EPI and 3D PRESTO for BOLD fMRI at 7 Tesla: I. Focal coverage

Robert L. Barry, Stephen C. Strother, J. Christopher Gatenby, John C. Gore
2011 NeuroImage  
In comparison, PRESTO also had high z-scores (higher than EPI for a matched in-plane resolution), the highest BW in the PE direction (producing images with superior geometric fidelity), the potential for  ...  This study provides evidence to support the use of 3D multi-shot acquisition sequences in lieu of single-shot EPI for ultra high field BOLD fMRI at 7T.  ...  Noiseless fMRI data with a perfect model would be mapped to (p=1,r=1).  ... 
doi:10.1016/j.neuroimage.2010.12.086 pmid:21232613 pmcid:PMC3049844 fatcat:zkrqggaoajhvjdzqbsfnwoiakq

Signal Fluctuation Sensitivity: an improved metric for optimizing detection of resting-state fMRI networks [article]

D.J. DeDora, S. Nedic, P. Katti, S. Arnab, L.L. Wald, A. Takahashi, K.R.A. Van Dijk, H.H. Strey, L.R. Mujica-Parodi
2015 arXiv   pre-print
We found that the de facto quality-metric for task-free fMRI, temporal signal to noise ratio (tSNR), correlated inversely with dynamic fidelity; thus, studies optimized for tSNR actually produced time-series  ...  blood oxygen level dependent (BOLD)-like inputs and fMRI outputs.  ...  (TR=2000-2010ms), increased time-resolution acquired for the Human Connectome Project (TR=1010-1080ms), and ultra-fast imaging paradigms (TR=802-824ms).  ... 
arXiv:1511.04345v1 fatcat:mzvcifjnxffcjfdnyksnt6mx3e

Ultra-high spatial resolution BOLD fMRI in humans using combined segmented-accelerated VFA-FLEET with a recursive RF pulse design [article]

Avery J.L. Berman
2020 Magnetic Resonance in Medicine   pre-print
Purpose To alleviate the spatial encoding limitations of single-shot EPI by developing multi-shot segmented EPI for ultra-high-resolution fMRI with reduced ghosting artifacts from subject motion and respiration  ...  Here, "FLEET" segment ordering--where segments are looped over before slices--was combined with a variable flip angle progression (VFA-FLEET) to improve inter-segment fidelity and maximize signal for fMRI  ...  Center for Biomedical Imaging; and was made possible by the resources provided by NIH Shared Instrumentation Grants S10-RR023043 and S10-RR019371.  ... 
doi:10.1002/mrm.28415 pmid:32705723 pmcid:PMC7722122 arXiv:2007.01950v1 fatcat:wund2pixifdppjfmvs6jucyd6m

The impact of ultra-high field MRI on cognitive and computational neuroimaging

Federico De Martino, Essa Yacoub, Valentin Kemper, Michelle Moerel, Kâmil Uludağ, Peter De Weerd, Kamil Ugurbil, Rainer Goebel, Elia Formisano
2018 NeuroImage  
This represents a unique and distinctive advantage that differentiates ultra high from lower field imaging and that can foster a tighter link between fMRI and computational modeling of neural networks.  ...  Compared to lower fields (3 T and below), ultra high field MRI has an increased sensitivity, which can be used to acquire functional images with greater spatial resolution, and greater specificity of the  ...  Here we aim at highlighting the potential for imaging brain function at ultra high fields (UHF, 7 T and above).  ... 
doi:10.1016/j.neuroimage.2017.03.060 pmid:28396293 fatcat:i6hjieismrfqnfjh3a53q7e624

Brain–heart interactions: challenges and opportunities with functional magnetic resonance imaging at ultra-high field

Catie Chang, Erika P. Raven, Jeff H. Duyn
2016 Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences  
(d) Applications of high-resolution functional magnetic resonance imaging at ultra-high field Capitalizing on recent advances in UHF imaging, a number of studies have demonstrated the ability to map features  ...  Functional magnetic resonance imaging at ultra-high field fMRI [25-27] is a method for non-invasively measuring changes in brain activity over time (see [28] for a recent review).  ... 
doi:10.1098/rsta.2015.0188 pmid:27044994 pmcid:PMC4822447 fatcat:gx7xotwgjrchjlqsqd6mq5qnjm

Statistical Power or More Precise Insights into Neuro-Temporal Dynamics? Assessing the Benefits of Rapid Temporal Sampling in fMRI [article]

Logan T Dowdle, Geoffrey Ghose, Kamil Ugurbil, Essa Yacoub, Luca Vizioli
2021 bioRxiv   pre-print
Functional magnetic resonance imaging (fMRI), a non-invasive and widely used human neuroimaging method, is most known for its spatial precision.  ...  With the intrinsic link between space and time in fMRI, this temporal renaissance also delivers improvements in spatial precision.  ...  such as that of ultra-fast fMRI.  ... 
doi:10.1101/2021.06.05.447164 fatcat:bidzlamz6baizdx4diftqc7gs4

Signal Fluctuation Sensitivity: An Improved Metric for Optimizing Detection of Resting-State fMRI Networks

Daniel J. DeDora, Sanja Nedic, Pratha Katti, Shafique Arnab, Lawrence L. Wald, Atsushi Takahashi, Koene R. A. Van Dijk, Helmut H. Strey, Lilianne R. Mujica-Parodi
2016 Frontiers in Neuroscience  
We found that the de facto quality-metric for task-free fMRI, temporal signal to noise ratio (tSNR), correlated inversely with dynamic fidelity; thus, studies optimized for tSNR actually produced time-series  ...  blood oxygen level dependent (BOLD)-like inputs and fMRI outputs.  ...  -1080 ms), and ultra-fast imaging paradigms (TR = 802-824 ms).  ... 
doi:10.3389/fnins.2016.00180 pmid:27199643 pmcid:PMC4854902 fatcat:sjs4cdae3jemnpod3leq573bdq

Magnetic Resonance Imaging at Ultrahigh Fields

Kamil Ugurbil
2014 IEEE Transactions on Biomedical Engineering  
Index Terms Functional imaging (fMRI); high field; magnetic resonance imaging (MRI); neuroimaging  ...  These nonuniformities were considered detrimental to the progress of imaging at high field strengths.  ...  His research focus has been the development of biological magnetic resonance imaging and spectroscopy using ultrahigh magnetic fields, with particular emphasis on neuroimaging and brain function.  ... 
doi:10.1109/tbme.2014.2313619 pmid:24686229 pmcid:PMC4135536 fatcat:qi7mqp5mavff7gpru2jmv7mx4i

A line through the brain: implementation of human line-scanning at 7T for ultra-high spatiotemporal resolution fMRI

Luisa Raimondo, Tomas Knapen, ĺcaro A.F Oliveira, Xin Yu, Serge O Dumoulin, Wietske van der Zwaag, Jeroen C.W Siero
2021 Journal of Cerebral Blood Flow and Metabolism  
To study the sub-millimeter structures and activity of the cortical gray matter, the field needs an fMRI method with high spatial and temporal resolution.  ...  We found a good correspondence of t-statistics values with 2D gradient-echo echo planar imaging (GE-EPI) BOLD fMRI data with the same temporal resolution and voxel volume (R = 0.6 ± 0.2).  ...  Ultra-high magnetic field strength MRI systems allow fMRI data acquisition with high spatial resolutions 5 because of the increases in signal-to-noise ratio (SNR) 6 and contrast-to-noise ratio (CNR  ... 
doi:10.1177/0271678x211037266 pmid:34415208 pmcid:PMC8756483 fatcat:7abw5umzenfpplhtvfndv764a4

The NonHuman Primate Neuroimaging Neuroanatomy Project [article]

Takuya Hayashi, Yujie Hou, Matthew F Glasser, Joonas A Autio, Kenneth Knoblauch, Miho Inoue-Murayama, Tim Coalson, Essa Yacoub, Stephen Smith, Henry Kennedy, David C Van Essen
2021 arXiv   pre-print
Our NonHuman Primate Neuroimaging & Neuroanatomy Project (NHP_NNP) is an international effort (6 laboratories in 5 countries) to: (i) acquire and analyze high-quality multi-modal brain imaging data of  ...  We are acquiring high-resolution structural, functional, and diffusion MRI data together with behavioral measures from over 100 individual macaques and marmosets in order to generate non-invasive measures  ...  For the ultra-high resolution in-vivo neuroimaging, ultra-high field MRI scanners have a great potential by combining parallel imaging hardwares and sequences for high-contrast & high-speed fMRI in NHP  ... 
arXiv:2010.00308v3 fatcat:xqccnaz2hzcs7pqedcutkvktea

The NonHuman Primate Neuroimaging & Neuroanatomy Project

Takuya Hayashi, Yujie Hou, Matthew F Glasser, Joonas A Autio, Kenneth Knoblauch, Miho Inoue-Murayama, Tim Coalson, Essa Yacoub, Stephen Smith, Henry Kennedy, David C Van Essen
2021 NeuroImage  
Our NonHuman Primate Neuroimaging & Neuroanatomy Project (NHP_NNP) is an international effort (6 laboratories in 5 countries) to: (i) acquire and analyze high-quality multi-modal brain imaging data of  ...  We are acquiring high-resolution structural, functional, and diffusion MRI data together with behavioral measures from over 100 individual macaques and marmosets in order to generate non-invasive measures  ...  For the ultra-high resolution in vivo neuroimaging, ultra-high field MRI scanners have a great potential by combining parallel imaging hardwares and sequences for high-contrast & high-speed fMRI in NHP  ... 
doi:10.1016/j.neuroimage.2021.117726 pmid:33484849 pmcid:PMC8079967 fatcat:tfv3sm6xpjfnfj2uarpqwnyc5u

Feasibility of spiral fMRI based on an LTI gradient model

Nadine N. Graedel, Lars Kasper, Maria Engel, Jennifer Nussbaum, Bertram J. Wilm, Klaas P. Pruessmann, S. Johanna Vannesjo
2021 NeuroImage  
GIRF-predicted reconstruction was tested for high-resolution (0.8 mm) fMRI at 7T.  ...  The reconstructions using nominal spiral trajectories contain substantial artifacts and the activation maps contain misplaced activation.  ...  This will include the raw coil data in ISM-RMRD format including the field monitoring data for the entire fMRI run the data collection doi: 10.3929/ethz-b-000487412 associated with Kasper et al. (2019  ... 
doi:10.1016/j.neuroimage.2021.118674 pmid:34718138 fatcat:aystarzttfaxxhipe55vw2ra2u
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