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Impact of tissue correction strategy on GABA-edited MRS findings

Eric C. Porges, Adam J. Woods, Damon G. Lamb, John B. Williamson, Ronald A. Cohen, Richard A.E. Edden, Ashley D. Harris
2017 NeuroImage  
The goal of applying tissue correction is to decrease the dependency of metabolite concentrations on the underlying voxel tissue composition.  ...  Tissue correction strategies have different underlying assumptions to account for different aspects of the voxel tissue fraction.  ...  We show that the selection of tissue correction strategy can impact the results; specifically, we show differences in the age-GABA+ and MoCA-GABA+ relationships depending on the voxel of interest and the  ... 
doi:10.1016/j.neuroimage.2017.08.073 pmid:28882635 pmcid:PMC5705271 fatcat:7v44hh353nbibd6553zivps3vu

Tissue correction for GABA-edited MRS: Considerations of voxel composition, tissue segmentation, and tissue relaxations

Ashley D. Harris, Nicolaas A.J. Puts, Richard A.E. Edden
2015 Journal of Magnetic Resonance Imaging  
Purpose-To develop a tissue correction for GABA-edited MRS that appropriately addresses differences in voxel gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) fractions.  ...  Furthermore, GM correction substantially (and non-linearly) increases the dependence of GABA measurements on GM/WM fraction, for example, by a factor of over four when the voxel GM tissue fraction is 50%  ...  These corrections are generally applied in manuscripts with the aim that findings based on corrected GABA values will not be impacted by differences in voxel segmentation, and against this benchmark they  ... 
doi:10.1002/jmri.24903 pmid:26172043 pmcid:PMC4615266 fatcat:eyevdcyg75bz3nczptaok7oe6u

Age-related differences in GABA: Impact of analysis technique [article]

Molly Simmonite, Scott J Peltier, Thad A Polk
2022 bioRxiv   pre-print
Here, we use data from a large healthy aging study to investigate the influence of three tissue correction strategies on age-group differences in GABA.  ...  ) and four tissue correction strategies.  ...  Acknowledgements Funding: This work was supported by the National Institute on Aging to TAP (R01AG05023)  ... 
doi:10.1101/2022.02.21.481330 fatcat:u7wr4icg2fatfpumfq6gwgdk4m

Comparison of seven modelling algorithms for GABA‐edited 1 H‐MRS

Alexander R. Craven, Pallab K. Bhattacharyya, William T. Clarke, Ulrike Dydak, Richard A. E. Edden, Lars Ersland, Pravat K. Mandal, Mark Mikkelsen, James B. Murdoch, Jamie Near, Reuben Rideaux, Deepika Shukla (+5 others)
2022 NMR in Biomedicine  
Edited MRS sequences are widely used for studying GABA in the human brain.  ...  GABA-edited (GABA+, TE = 68 ms MEGA-PRESS) data from 222 subjects at 20 sites were processed via a standardised pipeline, before modelling with FSL-MRS, Gannet, AMARES, QUEST, LCModel, Osprey and Tarquin  ...  , before applying tissue-class correction 34 using previously derived tissue fractions. 24 Full details on the adjustment for each algorithm are provided in the supporting information, section D.  ... 
doi:10.1002/nbm.4702 pmid:35078266 pmcid:PMC9203918 fatcat:paik7nzjjbh3ve5spmvk6boyjq

Comparison of seven modelling algorithms for GABA-edited 1H-MRS [article]

Alexander R. Craven, Pallab K. Bhattacharyya, William T. Clarke, Ulrike Dydak, Richard A. E. Edden, Lars Ersland, Pravat K. Mandal, Mark Mikkelsen, James B. Murdoch, Jamie Near, Reuben Rideaux, Deepika Shukla (+5 others)
2021 bioRxiv   pre-print
Edited MRS sequences are widely used for studying GABA in the human brain.  ...  GABA-edited (GABA+, TE = 68 ms MEGA-PRESS) data from 222 subjects at 20 sites were processed via a standardised pipeline, before modelling with FSL-MRS, Gannet, AMARES, QUEST, LCModel, Osprey and Tarquin  ...  applying tissue-class correction 34 using previously derived tissue fractions 24 .  ... 
doi:10.1101/2021.11.15.468534 fatcat:kemzc47oifanpbn7vrlsjk2b2i

Comparison of linear combination modeling strategies for GABA-edited MRS at 3T [article]

Helge J Z&oumlllner, Sofie Tapper, Steve C. N. Hui, Peter B. Barker, Richard A. E. Edden, Georg Oeltzschner
2021 bioRxiv   pre-print
This study explores different modeling strategies to adapt LCM for GABA-edited MRS.  ...  Purpose J-difference-edited spectroscopy is a valuable approach for the in vivo detection of γ-aminobutyric-acid (GABA) with MRS.  ...  No further tissue or relaxation corrections were applied.  ... 
doi:10.1101/2021.05.26.445817 fatcat:67ftwyxb4faltfgi2sr47t7rxq

Role of gamma-amino-butyric acid in the dorsal anterior cingulate in age-associated changes in cognition

Stefano Marenco, Christian Meyer, Jan Willem van der Veen, Yan Zhang, Ryan Kelly, Jun Shen, Daniel R. Weinberger, Dwight Dickinson, Karen F. Berman
2018 Neuropsychopharmacology  
Spectral-editing MRS at 3 T was used to measure GABA in the dorsal anterior cingulate cortex (dACC) for a large sample of healthy volunteers (N = 229) aged 18-55.  ...  Mediation analysis revealed that GABA in the dACC mediated the effect of age on WCST performance (p < 0.01).  ...  Effects of age on metabolites Both our measures of GABA+ decreased with advancing age. This is consistent with findings by Gao et al. [18] for GABA+/Cre, and those of Rowland et al.  ... 
doi:10.1038/s41386-018-0134-5 pmid:30050047 fatcat:kjordy7oubdhrnl2zcuxs5wk7e

Multi-Regional Investigation of the Relationship between Functional MRI Blood Oxygenation Level Dependent (BOLD) Activation and GABA Concentration

Ashley D. Harris, Nicolaas A. J. Puts, Brian A. Anderson, Steven Yantis, James J. Pekar, Peter B. Barker, Richard A. E. Edden, Xi Luo
2015 PLoS ONE  
This was followed by GABA-edited MRS acquisitions and then GABA and BOLD Correlations across Multiple Brain Regions PLOS ONE |  ...  In 18 healthy participants, we performed edited MRS measurements of GABA and BOLD-fMRI experiments using regionally related activation paradigms.  ...  MRS acquisition and analysis GABA-edited MRS data were acquired using the MEGA-PRESS experiment [18] , with 14 ms sinc-Gaussian editing pulses applied at 1.9 ppm in the 'ON' condition and 7.46 ppm in  ... 
doi:10.1371/journal.pone.0117531 pmid:25699994 pmcid:PMC4336183 fatcat:pqzh36suwfdjrd5kpcrdhzt2gu

The trajectory of cortical GABA across the lifespan, an individual participant data meta-analysis of edited MRS studies

Eric C Porges, Greg Jensen, Brent Foster, Richard AE Edden PhD, Nicolaas AJ Puts
2021 eLife  
In this study, 8 suitable datasets were integrated to generate a model of the trajectory of frontal GABA estimates (as reported through edited MRS; both expressed as ratios and in institutional units).  ...  GABA is the principal inhibitory neurotransmitter in the human brain and can be measured with Magnetic Resonance Spectroscopy (MRS).  ...  GABA findings presented here but the impact of reference compound needs to be considered.  ... 
doi:10.7554/elife.62575 pmid:34061022 pmcid:PMC8225386 fatcat:cxgbh73rlzcobbc74julf7rq4y

Current practice in the use of MEGA-PRESS spectroscopy for the detection of GABA

Paul G. Mullins, David J. McGonigle, Ruth L. O'Gorman, Nicolaas A.J. Puts, Rishma Vidyasagar, C. John Evans, Richard A.E. Edden
2014 NeuroImage  
to the field to avoid some of the pitfalls inherent in the acquisition and processing of edited MRS for GABA.  ...  At a recent meeting held at Cardiff University, a number of spectroscopy groups met to discuss the acquisition, analysis and interpretation of GABA-edited MR spectra.  ...  Cardiff Symposium on MRS of GABA, 22-23 August 2011: Dr. Matthew J. Brookes.  ... 
doi:10.1016/j.neuroimage.2012.12.004 pmid:23246994 pmcid:PMC3825742 fatcat:zbtoo4yixjcevonkaz54zvetue

Dorsolateral Prefrontal Cortex GABA Concentration in Humans Predicts Working Memory Load Processing Capacity

Jong H. Yoon, Anthony Grandelis, Richard J. Maddock
2016 Journal of Neuroscience  
Given that WM is required for many of the most characteristic cognitive and behavioral capabilities in humans, this finding could have a significant impact on our understanding of the neural basis of complex  ...  We found that individuals with lower DLPFC GABA showed greater performance degradation with higher load, accounting for 31% of variance, p (corrected) ϭ 0.015.  ...  It is important to note that MRS measures the total tissue content of GABA within a region. Most brain tissue GABA is in the cytosolic or vesicular compartments of GABAergic neurons.  ... 
doi:10.1523/jneurosci.1970-16.2016 pmid:27852785 pmcid:PMC5125231 fatcat:mq7llik6m5adzhmjh5qcogsx74

Comparison of methods for spectral alignment and signal modelling of GABA-edited MR spectroscopy data

Reuben Rideaux, Mark Mikkelsen, Richard A. Edden
2021 NeuroImage  
and phase drift correction) and six GABA signal modelling methods.  ...  We analyse a diverse dataset of 432 MEGA-PRESS scans targeting multiple brain regions and find that alignment to the creatine (Cr) signal produces GABA+ estimates that account for approximately twice as  ...  In MRS studies, this relationship is often considered a nuisance, and attempts are made to reduce its impact by performing a correction based on the voxel tissue composition ( Gasparovic et al., 2006  ... 
doi:10.1016/j.neuroimage.2021.117900 pmid:33652146 fatcat:gvoooufmsre5rknbui77424xni

Continuous and intermittent theta burst stimulation to the visual cortex do not alter GABA and glutamate concentrations measured by magnetic resonance spectroscopy

Karlene S. Stoby, Sara A. Rafique, Georg Oeltzschner, Jennifer K. E. Steeves
2022 Brain and Behavior  
We investigated the effects of iTBS and cTBS to the primary visual cortex (V1) on composite levels of gamma-aminobutyric acid + co-edited macromolecules (GABA+) and glutamate + glutamine (Glx) since these  ...  GABA+ and Glx were quantified in vivo at the stimulation site using spectral-edited proton magnetic resonance spectroscopy (1 H-MRS) at 3T.  ...  For MEGA-PRESS of GABA+, water-referenced quantification including tissue-correction shows similar levels of performance to Cr referencing, and the reliability of the two referencing strategies is comparable  ... 
doi:10.1002/brb3.2478 pmid:35029058 pmcid:PMC8865152 fatcat:5rauydirgnb33iu6tnqnkmbn7a

The trajectory of cortical GABA levels across the lifespan: An individual participant data meta-analysis of edited MRS studies [article]

Eric C Porges, Greg Jensen, Brent Foster, Richard A E Edden, Nicolaas A J Puts
2020 bioRxiv   pre-print
GABA is the principal inhibitory neurotransmitter in the human brain and can be measured with Magnetic Resonance Spectroscopy (MRS).  ...  The information gained will provide a general framework to inform expectations of future studies based on the age of the population being studied.  ...  It is well known that voxel tissue composition has a significant impact on the quantification of GABA levels .  ... 
doi:10.1101/2020.07.23.218792 fatcat:cpzgoofh55aifhh5zbjdybyt6a

Regional GABA Concentrations Modulate Inter-network Resting-state Functional Connectivity

Xi Chen, Xiaoying Fan, Yuzheng Hu, Chun Zuo, Susan Whitfield-Gabrieli, Daphne Holt, Qiyong Gong, Yihong Yang, Diego A Pizzagalli, Fei Du, Dost Ongur
2018 Cerebral Cortex  
To address this issue, we used functional MRI to measure whole-brain BOLD signal during resting-state and task-evoked conditions, and MR spectroscopy (MRS) to quantify GABA and glutamate concentrations  ...  These findings indicate that GABA in the MPFC is potentially involved in orchestrating between-network brain activity at rest and during task performance.  ...  Conflict of Interest: None declared.  ... 
doi:10.1093/cercor/bhy059 pmid:29608677 fatcat:mezqg4oaybgovafjvgmvbnd3ky
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