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A Sliding Time-Window ICA Reveals Spatial Variability of the Default Mode Network in Time

Vesa Kiviniemi, Tapani Vire, Jukka Remes, Ahmed Abou Elseoud, Tuomo Starck, Osmo Tervonen, Juha Nikkinen
2011 Brain Connectivity  
The spatial similarity of successive DMN maps varied over time at low frequencies and presented a 1/f power spectral pattern.  ...  In conclusion, SliTICA shows marked spatial variance of DMN activity in time, which may offer a more comprehensive measurement of the overall functional activity of a network.  ...  Acknowledgments Academy of Finland grants 111711 and 123772, a Finnish Medical Foundation grant, and a Finnish Neurological Association grant contributed to this study.  ... 
doi:10.1089/brain.2011.0036 pmid:22432423 fatcat:ritf62iuvrf2bkaxy7lnkghmwu

Real-Time Functional Magnetic Resonance Imaging

Mark S. Cohen
2001 Methods  
This dramatically limits in the detection of brain activity via the relatively indirect coupling the possibility of "real-time" MRI.  ...  We describe here our preferred method of real-time quite small, and limiting, to normal applications.  ...  Aside from the obvious risks involved in such in this brain region without loss of language/motor funcapproaches, the technique has many technical limitation?"  ... 
doi:10.1006/meth.2001.1235 pmid:11812206 fatcat:athqfdyvfngipknk6wrd5nslwm

Pathophysiological distortions in time perception and timed performance

Melissa J. Allman, Warren H. Meck
2011 Brain  
Distortions in time perception and timed performance are presented by a number of different neurological and psychiatric conditions (e.g.  ...  These findings are used to evaluate the Striatal Beat Frequency Theory, which is a neurobiological model of interval timing based upon the coincidence detection of oscillatory processes in corticostriatal  ...  differences in the location of the point of subjective equality for temporal bisection and increased sources of non-scalar variance (difference limen and Weber ratio).  ... 
doi:10.1093/brain/awr210 pmid:21921020 pmcid:PMC3491636 fatcat:myikskg565h5zge2apulcwqlh4

Short echo time proton magnetic resonance spectroscopy in Alzheimer's disease: a longitudinal multiple time point study

J. M. Schott, C. Frost, D. G. MacManus, F. Ibrahim, A. D. Waldman, N. C. Fox
2010 Brain  
Short echo time localized proton magnetic resonance spectroscopy provides quantification of brain metabolites, including N-acetyl-aspartate, myo-inositol, creatine/phosphocreatine and choline-containing  ...  A total of 42 patients and 22 controls each had up to six magnetic resonance spectroscopy examinations over a 2-year period, using a midline posterior cingulate single-voxel point resolved spectroscopy  ...  Acknowledgements The authors are grateful to the patients and carers who participated in the study and to Dr Jessica Simon for early work on the project.  ... 
doi:10.1093/brain/awq208 pmid:20739347 pmcid:PMC2965422 fatcat:aijvfkqaargvddiyndhetzd6aa

Real-time functional MRI using pseudo-continuous arterial spin labeling

Luis Hernandez-Garcia, Hesamoddin Jahanian, Mark K. Greenwald, Jon-Kar Zubieta, Scott J. Peltier
2011 Magnetic Resonance in Medicine  
Because of very limited processing time available in real-time fMRI applications, quantifying the BOLD signal in real time poses substantial challenges.  ...  The user is also able to track the time course of individual time courses and interactively selects a region of interest as a nuisance covariate.  ...  By tracking individual time courses and by interactively selecting an ROI as a nuisance covariate, we were able to improve signal detection in real time.  ... 
doi:10.1002/mrm.22922 pmid:21446035 pmcid:PMC3097282 fatcat:coiu7tpbgfdubmxgdeb3qwzere

Detecting and adjusting for artifacts in fMRI time series data

Jörn Diedrichsen, Reza Shadmehr
2005 NeuroImage  
We present a new method to detect and adjust for noise and artifacts in functional MRI time series data.  ...  We note that the assumption of stationary variance, which is central to the theoretical treatment of fMRI time series data, is often violated in practice.  ...  Acknowledgments The work was supported through grants from the NIH (NS37422) and the Human Frontiers Science Program. We are grateful to the staff of the F.M.  ... 
doi:10.1016/j.neuroimage.2005.04.039 pmid:15975828 pmcid:PMC1479857 fatcat:x7ccvazh3zc7fg7znbcqrutv5y

Structural Correlation-based Outlier Rejection (SCORE) algorithm for arterial spin labeling time series

Sudipto Dolui, Ze Wang, Russell T. Shinohara, David A. Wolk, John A. Detre
2016 Journal of Magnetic Resonance Imaging  
Purpose-To propose and validate Structural Correlation based Outlier REjection (SCORE), a novel algorithm for removal of artifacts arising from outlier control-label pairs in 2D Arterial Spin Labeling  ...  Results-SCORE coupled with a preprocessing step to discard few extreme outliers (combined algorithm referred to as SCORE+) reduced wsCV up to 21% in grey matter and 39% in smaller ROIs compared to the  ...  Data collection and sharing for this project was funded by the Alzheimer's Disease Neuroimaging Initiative (ADNI) (National Institutes of Health Grant U01 AG024904) and DOD ADNI (Department of Defense  ... 
doi:10.1002/jmri.25436 pmid:27570967 pmcid:PMC5332532 fatcat:ydjpzxd3srfe7izixld7pctyee

Ground-truth resting-state signal provides data-driven estimation and correction for scanner distortion of fMRI time-series dynamics [article]

Rajat Kumar, Liang Tan, Alan Kriegstein, Andrew Lithen, Jonathan R. Polimeni, Helmut H. Strey, Lilianne R. Mujica-Parodi
2020 arXiv   pre-print
To address this problem, we first designed and built a phantom capable of providing dynamic signals equivalent to that of the resting-state brain.  ...  Tests on dynamic phantom time-series showed a 4- to 7-fold increase in ST-SNR and about 40-70% increase in Dynamic Fidelity after denoising.  ...  There is a clear indication of scanner issues/increasing scanner instability between May and September 2019. Additionally, variance in scanner instability can be noticed on a daily basis.  ... 
arXiv:2004.06760v3 fatcat:djqg3prljvgfhgiuqg7m2rdmty

Neurobiology of perceptual and motor timing in children with spina bifida in relation to cerebellar volume

Maureen Dennis, Kim Edelstein, Ross Hetherington, Kim Copeland, Jon Frederick, Susan E. Blaser, Larry A. Kramer, James M. Drake, Michael Brandt, Jack M. Fletcher
2004 Brain  
between timing and cerebellar volumes.  ...  Duration perception was correlated with cerebellar volumes, and the number of valid tapping trials was correlated with cerebellar volumes in the SB group, which data demonstrate structure±function relations  ...  This work was supported by National Institute of Child Health and Human Development Grant P01 HD35946`Spina Bi®da: Cognitive and Neurobiological Variability'.  ... 
doi:10.1093/brain/awh154 pmid:15069019 fatcat:4zuuq7oejbhdzdyinj5uqpk5xy

Time-Resolved Integrative Optical Imaging of Diffusion during Spreading Depression [article]

Jan Hrabe, Sabina Hrabetova
2019 bioRxiv   pre-print
We present a theory for Time-Resolved Integrative Optical Imaging (TR-IOI) that incorporates time-dependent effective diffusion coefficient in homogeneous anisotropic media and time-dependent nonspecific  ...  We were able to achieve time resolution of approximately one second, an improvement of at least ten times compared to the standard methods for extracellular diffusion measurement.  ...  AUTHOR CONTRIBUTIONS JH and SH designed the research. JH carried out theoretical and programming work while SH carried out experimental work. JH and SH wrote the article.  ... 
doi:10.1101/648972 fatcat:rt7xoozanbf7ppazeyt4cv6znu

Determinants of Cerebral Atrophy Rate at the Time of Diagnosis of Multiple Sclerosis

Bas Jasperse, Arjan Minneboo, Vincent de Groot, Nynke F. Kalkers, Paul E. van Helden, Bernard M. J. Uitdehaag, Frederik Barkhof, Chris H. Polman
2007 Archives of Neurology  
PBVC/y and yielded a regression model that explained 31.2% of the variance in PBVC/y.  ...  Conclusions: In patients with recently diagnosed multiple sclerosis, the extent of accumulated brain tissue loss and overall lesion load partly explain the subsequent rate of cerebral atrophy.  ...  Acknowledgment: We thank the patients who participated in this study.  ... 
doi:10.1001/archneur.64.2.190 pmid:17296834 fatcat:hmzmca47hzbg3klhf5jhfq66ti

Traumatic Brain Injury, Aging and Reaction Time

D.T. Stuss, L.L. Stethem, T.W. Picton, E.E. Leech, G. Pelchat
1989 Canadian Journal of Neurological Sciences  
Individuals over age 60 and patients of any age with TBI demonstrated slower RT with choice RT tests.  ...  ABSTRACT:The effects of traumatic brain injury (TBI) and aging were compared on tests of simple and complex reaction time (RT). Simple RT was not significantly affected by aging or TBI.  ...  Severe TBI results in widespread brain damage; 13 -14 aging also causes diffuse loss of neurons. 15 -16 Both aging and TBI may cause focal frontal lobe dysfunction.  ... 
doi:10.1017/s0317167100028833 fatcat:5bjajhxqznhyphmsuvlegcugru

Investigating directed cortical interactions in time-resolved fMRI data using vector autoregressive modeling and Granger causality mapping

Rainer Goebel, Alard Roebroeck, Dae-Shik Kim, Elia Formisano
2003 Magnetic Resonance Imaging  
We present a framework aimed to reveal directed interactions of activated brain areas using time-resolved fMRI and vector autoregressive (VAR) modeling in the context of Granger causality.  ...  fluctuations in BOLD-like signal time courses.  ...  variation in individual voxel time-courses.  ... 
doi:10.1016/j.mri.2003.08.026 pmid:14725933 fatcat:mxa7jueg75bntajp4nsrcklppu

Performance assessment of time-domain optical brain imagers, part 2: nEUROPt protocol

Heidrun Wabnitz, Alexander Jelzow, Mikhail Mazurenka, Oliver Steinkellner, Rainer Macdonald, Daniel Milej, Norbert Zolek, Michal Kacprzak, Piotr Sawosz, Roman Maniewski, Adam Liebert, Salavat Magazov (+11 others)
2014 Journal of Biomedical Optics  
This protocol addresses the characteristic of optical brain imaging to detect, localize, and quantify absorption changes in the brain.  ...  The nEUROPt protocol is one of two new protocols developed within the European project nEUROPt to characterize the performances of time-domain systems for optical imaging of the brain.  ...  the detection, localization, and quantification of absorption changes in the brain.  ... 
doi:10.1117/1.jbo.19.8.086012 pmid:25121480 fatcat:55ljf2b2xnffrf5gefkspdiv4u

Regional brain atrophy predicts time to conversion to Alzheimer's disease, dependent on baseline volume

Hossein Tabatabaei-Jafari, Marnie E. Shaw, Erin Walsh, Nicolas Cherbuin
2019 Neurobiology of Aging  
This study aims to address this question by exploring the contribution of baseline brain volume and annual volume change, using Cox regression, in predicting the time to conversion.  ...  The results revealed that the volumes of all the brain areas considered were predictive of the time to conversion from MCI to AD.  ...  Acknowledgments Data collection and sharing for this project was funded by the Alzheimer's Disease Neuroimaging Initiative (ADNI; National Institutes of Health Grant U01 AG024904). ADNI  ... 
doi:10.1016/j.neurobiolaging.2019.08.033 pmid:31585370 fatcat:cx3gxgwkxbdndcpsgufxhtiyim
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