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Wavelet minimum description length detrending for near-infrared spectroscopy

Kwang Eun Jang, Sungho Tak, Jinwook Jung, Jaeduck Jang, Yong Jeong, Jong Chul Ye
2009 Journal of Biomedical Optics  
The minimum description length ͑MDL͒ principle plays an important role in preventing over-or underfitting and facilitates optimal model order selection for the global trend estimate.  ...  Recently, the general linear model ͑GLM͒, which is a standard method for functional MRI ͑fMRI͒ analysis, has been employed for quantitative analysis of NIRS data.  ...  Acknowledgments This work was supported by the IT R&D program of MKE/ IITA ͓2008-F-021-01͔. K. E. Jang gratefully acknowledges support from a Kim Bo Jung Scholarship. K. E.  ... 
doi:10.1117/1.3127204 pmid:19566297 fatcat:qlwj4fcy4ndexkbklck5e3baam

A Data-Driven Sparse GLM for fMRI Analysis Using Sparse Dictionary Learning With MDL Criterion

Kangjoo Lee, Sungho Tak, Jong Chul Ye
2011 IEEE Transactions on Medical Imaging  
Using simulation and real fMRI experiments, we show that the proposed method can adapt individual variation better compared to the conventional ICA methods.  ...  Furthermore, an MDL based model order selection rule is shown to be essential in selecting unknown sparsity level for sparse dictionary learning.  ...  ACKNOWLEDGMENT This research was supported by the Korea Science and Engineering Foundation, Grant No.:2010-N01100084. We thank Dr. Yong Jeong and Mr.  ... 
doi:10.1109/tmi.2010.2097275 pmid:21138799 fatcat:ewpwapekdfgv7lam44dxxpplge

Commentary on the statistical properties of noise and its implication on general linear models in functional near-infrared spectroscopy

Theodore J. Huppert
2016 Neurophotonics  
In the majority of NIRS functional brain studies, analysis of this data is based on a statistical comparison of hemodynamic levels between a baseline and task or between multiple task conditions by means  ...  Published by SPIE under a Creative Commons Attribution 3.0 Unported License.  ...  Here, the same AR model is applied across all spatial channels and is often used in addition to the DCT or MDL prewhitening methods.  ... 
doi:10.1117/1.nph.3.1.010401 pmid:26989756 pmcid:PMC4773699 fatcat:4gem447s2vccjfhmuowc4cabhi

ICA Component Selection Based on Sparse Activelet Reconstruction for fMRI Analysis in Refractory Focal Epilepsy

Borbala Hunyadi, Bogdan Mijovic, Simon Tousseyn, Patrick Dupont, Wim Van Paesschen, Sabine Van Huffel, Maarten De Vos
2012 2012 Second International Workshop on Pattern Recognition in NeuroImaging  
Standard analysis techniques rely on the principle that fMRI can provide accurate localization of hemodynamic changes corresponding to events observed on EEG.  ...  EEG-fMRI is a recently emerging tool that can be used in the presurgical evaluation of focal epilepsy patients.  ...  The BOLD signal recorded by the fMRI can be written as follows: ( ) = ∑ ℎ( − ) + ( ), (1) where ( ) is a unknown noise term comprising noise, baseline, drifts, physiological artifacts and possibly other  ... 
doi:10.1109/prni.2012.16 dblp:conf/prni/HunyadiMTDPHV12 fatcat:iopnqio7jjghfjo74iz4qe3jla

Quantification of CMRO2without hypercapnia using simultaneous near-infrared spectroscopy and fMRI measurements

Sungho Tak, Jaeduck Jang, Kangjoo Lee, Jong Chul Ye
2010 Physics in Medicine and Biology  
In this paper, a novel method to estimate CMRO 2 without hypercapnia is described using simultaneous measurements of NIRS and fMRI.  ...  Based on the new methods, we found that group average CBF, CMRO 2 , cerebral blood volume (CBV), and BOLD changes within activation of the primary motor cortex during a finger tapping task increased by  ...  This research was supported by the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korean government (MEST) (no 2009-0081089).  ... 
doi:10.1088/0031-9155/55/11/017 pmid:20479515 fatcat:74m52evq7fepfkq22vf7r7n4be

The effect of ageing on fMRI: Correction for the confounding effects of vascular reactivity evaluated by joint fMRI and MEG in 335 adults

Kamen A. Tsvetanov, Richard N. A. Henson, Lorraine K. Tyler, Simon W. Davis, Meredith A. Shafto, Jason R. Taylor, Nitin Williams, Cam-CAN, James B. Rowe
2015 Human Brain Mapping  
The present work addressed these issues by comparing RSFA (i.e., rsfMRI variability) to proxy measures of (i) cardiovascular function in terms of heart rate (HR) and heart rate variability (HRV) and (ii  ...  In functional magnetic resonance imaging (fMRI) research one is typically interested in neural activity.  ...  ACKNOWLEDGMENTS The Cambridge Centre for Ageing and Neuroscience (Cam-CAN) research was supported by the Biotechnology and Biological Sciences Research Council (grant number BB/H008217/1).  ... 
doi:10.1002/hbm.22768 pmid:25727740 pmcid:PMC4730557 fatcat:wy2oe2gktvdkthgbaghjbslh6y

Effect of MRgFUS treatment on cortical activity in Parkinson's disease: a fNIRS study

Sergio Gurgone, Giuseppe Acri, Lilla Bonanno, Francesco Caridi, Simona De Salvo, Silvia Marino, Nunzio Muscarà, Valentina Venuti, Andrea D'Avella
2021 Atti della Accademia Peloritana dei Pericolanti : Classe di Scienze Fisiche, Matematiche e Naturali  
On one side, MRgFUS enables non-invasive thalamotomy by combining FUS for tissue ablation and MR for targeting and monitoring.  ...  approach, based on Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) technique and functional Near Infrared Spectroscopy (fNIRS), was applied for treatment and monitoring of patients affected by  ...  Because fNIRS signals are generally affected by a global drift, we also included in the analysis the wavelet Minimum Description Length (wavelet-MDL) algorithm described in (Jang et al. 2009) .  ... 
doi:10.1478/aapp.992a5 doaj:0d9feb8afd3d467fb4505d0e1f81aea8 fatcat:tuzlvxj44nfinbgjh47g6tcsaq

Penalized partially linear models using sparse representations with an application to fMRI time series

J.M. Fadili, E. Bullmore
2005 IEEE Transactions on Signal Processing  
Index Terms-fMRI, neuroimaging, partially linear models, penalized estimation, sparse representations, wavelets.  ...  We also give a fast estimation algorithm. The method is then generalized to handle the case of overcomplete representations.  ...  The sparse representation-based PLM has been demonstrated to describe parsimoniously (with few coefficients) the fMRI response to a stimulus contaminated by Gaussian noise and a systematic baseline drift  ... 
doi:10.1109/tsp.2005.853207 fatcat:2ecsxlarnzggpemi47eukvytru

Measuring relative timings of brain activities using fMRI

Santosh B. Katwal, John C. Gore, J. Christopher Gatenby, Baxter P. Rogers
2013 NeuroImage  
This capability may contribute towards the study of communication within the brain by assessing the temporal sequences of various brain processes (mental chronometry).  ...  The practical limit of fMRI for detecting the relative timings of brain activities is not known.  ...  Acknowledgments This research was supported by National Institutes of Health, NIH 5R01EB000461 (Principal Investigator JCG).  ... 
doi:10.1016/j.neuroimage.2012.10.052 pmid:23110880 pmcid:PMC3593774 fatcat:ujrjmzhx25didhn5awz4ofbipy

LEICA: Laplacian eigenmaps for group ICA decomposition of fMRI data

Chihuang Liu, Joseph JaJa, Luiz Pessoa
2018 NeuroImage  
The test results show that the extracted spatial maps from LEICA are meaningful functional networks similar to those produced by some of the best known methods.  ...  Independent component analysis (ICA) is a data-driven method that has been increasingly used for analyzing functional Magnetic Resonance Imaging (fMRI) data.  ...  Acknowledgment The authors gratefully acknowledge the support provided by  ... 
doi:10.1016/j.neuroimage.2017.12.018 pmid:29246846 pmcid:PMC6293470 fatcat:emaqontiibe67cgkxxxvx4wwtm

Schizophrenia alters intra-network functional connectivity in the caudate for detecting speech under informational speech masking conditions

Yingjun Zheng, Chao Wu, Juanhua Li, Ruikeng Li, Hongjun Peng, Shenglin She, Yuping Ning, Liang Li
2018 BMC Psychiatry  
Methods: Using functional magnetic resonance imaging (fMRI), this study investigated differences between people with schizophrenia (n = 19, mean age = 33 ± 10 years) and their matched healthy controls  ...  A minimum-description-length (MDL) algorithm [41] was used to determine the number of source locations. The average (integral) number of the components was 20, estimated across all participants.  ...  Using the functional resonance magnetic imaging (fMRI) methods, this study aimed to explore differences specifically in intra-network FC for detecting target speech against speech masking between listeners  ... 
doi:10.1186/s12888-018-1675-1 pmid:29618332 pmcid:PMC5885301 fatcat:oylijrscrrdc5bd7u7p4ghcveu

Data Processing in Functional Near-Infrared Spectroscopy (fNIRS) Motor Control Research

Patrick W. Dans, Stevie D. Foglia, Aimee J. Nelson
2021 Brain Sciences  
Spike MAs and baseline shifts are caused by rapid changes in optode position across the scalp. Baseline drift can occur due to slow, constant movement of optodes across the scalp.  ...  Spike MAs and baseline shifts are caused by rapid changes in optode position across the scalp. Baseline drift can occur due to slow, constant movement of optodes across the scalp.  ... 
doi:10.3390/brainsci11050606 pmid:34065136 fatcat:23i5a7z3uzeefluiapnhobnah4

Statistical analysis of fNIRS data: A comprehensive review

Sungho Tak, Jong Chul Ye
2014 NeuroImage  
However, fNIRS signals are highly corrupted by measurement noises and physiology-based systemic interference.  ...  of the existing inference methods for fNIRS analysis can be derived as special cases.  ...  Source S is then estimated by using a unmixing matrix W such thatŜ ¼ WY, where W = A −1 is estimated by several methods, including maximum likelihood estimation .  ... 
doi:10.1016/j.neuroimage.2013.06.016 pmid:23774396 fatcat:pc3vhagvy5b3lidlq53ayu7h4i

A Minimum Description Length Approach to Multitask Feature Selection [article]

Brian Tomasik
2009 arXiv   pre-print
Section 3 surveys hypothesis testing by regression with a single response, focusing on the parallel between the standard Bonferroni correction and an MDL approach.  ...  Section 1 introduces feature selection for regression, focusing on ell_0 regularization methods and their interpretation within a Minimum Description Length (MDL) framework.  ...  ., the content of Section 2) was originated by Jing Zhou, Dean Foster, and Lyle Ungar, who drafted a paper outlining the theory and some preliminary experiments.  ... 
arXiv:0906.0052v1 fatcat:tvuflc7fo5garfdvkfkbwnw65i

Altered Connectivity Pattern of Hubs in Default-Mode Network with Alzheimer's Disease: An Granger Causality Modeling Approach

Xiaoyan Miao, Xia Wu, Rui Li, Kewei Chen, Li Yao, Tsuneya Ikezu
2011 PLoS ONE  
fMRI data of 12 young subjects, 16 old normal controls and 15 AD patients respectively.  ...  Principal Findings: To address these issues, we investigated the causal influences between any pair of nodes within the DMN using Granger causality analysis and graph-theoretic methods on resting-state  ...  Global signal was removed from the time series to minimize the variance contributed by physiological artifacts and scanner drift [72] .  ... 
doi:10.1371/journal.pone.0025546 pmid:22022410 pmcid:PMC3191142 fatcat:lhcavhiu25a7ponqxcqtkwtkme
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